Literatura académica sobre el tema "Essential amino acid"
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Artículos de revistas sobre el tema "Essential amino acid"
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de Almeida Bicudo, Alvaro Jose y Jose Eurico Possebon Cyrino. "Evaluation of methods to estimate the essential amino acids requirements of fish bfrom the muscle amino acid profile". Latin American Journal of Aquatic Research 42, n.º 1 (10 de marzo de 2014): 271–75. http://dx.doi.org/10.3856/vol42-issue1-fulltext-23.
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Fussell, Maya, Allison Contillo, Heidi Druehl y Nancy R. Rodriguez. "Essential Amino Acid Density". Nutrition Today 56, n.º 2 (marzo de 2021): 70–75. http://dx.doi.org/10.1097/nt.0000000000000466.
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Yoshimura, N. N. "Intravenous Essential Amino Acid Therapy". Nephron 67, n.º 1 (1994): 131. http://dx.doi.org/10.1159/000187909.
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FITZGERALD, Lisa M. y Alina M. SZMANT. "Biosynthesis of ‘essential’ amino acids by scleractinian corals". Biochemical Journal 322, n.º 1 (15 de febrero de 1997): 213–21. http://dx.doi.org/10.1042/bj3220213.
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Animals rely on their diet for amino acids that they are incapable either of synthesizing or of synthesizing in sufficient quantities to meet metabolic needs. These are the so-called ‘essential amino acids’. This set of amino acids is similar among the vertebrates and many of the invertebrates. Previously, no information was available for amino acid synthesis by the most primitive invertebrates, the Cnidaria. The purpose of this study was to examine amino acid synthesis by representative cnidarians within the Order Scleractinia. Three species of zooxanthellate reef coral, Montastraea faveolata, Acropora cervicornis and Porites divaricata, and two species of non-zooxanthellate coral, Tubastrea coccinea and Astrangia poculata, were incubated with 14C-labelled glucose or with the 14C-labelled amino acids glutamic acid, lysine or valine. Radiolabel tracer was followed into protein amino acids. A total of 17 amino acids, including hydroxyproline, were distinguishable by the techniques used. Of these, only threonine was not found radiolabelled in any of the samples. We could not detect tryptophan or cysteine, nor distinguish between the amino acid pairs glutamic acid and glutamine, or aspartic acid and asparagine. Eight amino acids normally considered essential for animals were made by the five corals tested, although some of them were made only in small quantities. These eight amino acids are valine, isoleucine, leucine, tyrosine, phenylalanine histidine, methionine and lysine. The ability of cnidarians to synthesize these amino acids could be yet another indicator of a separate evolutionary history of the cnidarians from the rest of the Metazoa.
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Islary, Anuck, Jatin Sarmah y Sanjay Basumatary. "Amino Acid Composition of Five Wild Edible Fruits of Assam, North-East India". Asian Journal of Chemistry 31, n.º 4 (27 de febrero de 2019): 825–28. http://dx.doi.org/10.14233/ajchem.2019.21749.
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In this study, amino acids profiles of 5 wild edible fruits viz. Grewia sapida, Ottelia alismoides, Aporosa dioica, Antidesma bunius and Eugenia operculata found in Assam of North-East India were investigated by RP-HPLC equipped with C18 column. A total of 17 amino acids in varying compositions were identified and 8 of these are essential amino acids and 9 of these are non-essential amino acids. In all of the 5 wild fruits, 6 different amino acids were identified and these were aspartic acid (1.151-3.837 %), glutamic acid (2.283-9.667 %), arginine (0.904-7.187 %), valine (0.142-1.029 %), leucine (1.849-19.665 %), and histidine (0.467-12.986 %). A. bunius fruit showed the highest non-essential amino acid content whereas O. alismoides fruit displayed the highest essential amino acid content. Leucine was found to be the most abundant essential amino acid whereas glutamic acid was detected to be the most abundant non-essential amino acid.
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Lošák, T., J. Hlušek, R. Filipčík, L. Pospíšilová, J. Maňásek, K. Prokeš, F. Buňka, S. Kráčmar, A. Martensson y F. Orosz. "Effect of nitrogen fertilization on metabolisms of essential and non-essential amino acids in field-grown grain maize (Zea mays L.)". Plant, Soil and Environment 56, No. 12 (16 de diciembre de 2010): 574–79. http://dx.doi.org/10.17221/288/2010-pse.
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In two-year field experiments, nitrogen (N) in the form of urea (0, 120 and 240 kg N/ha) was applied to grain maize (Zea mays L.) hybrid KWS 2376. The two-year mean content of total grain N at harvest was 1.54%. The highest N dose reduced most of the 17 amino acids (AA) analysed in the grain compared with the other treatments. Possible reasons for this could be an adverse effect on the tricarboxylic acid cycle or deficiency of carbon skeletons for the assimilation of NH<sub>4</sub><sup>+</sup> into amides and amino acids. The content of the limiting amino acid lysine was not influenced by N fertilisation, with a mean two-year content of 2.02 mg/g DM. Taking into account the differences in fertilisation, the effect of the year was seen in the maximal accumulation of amino acids serine, proline, methionine, threonine, arginine and lysine. Increasing rates of nitrogen reduced the accumulation of asparagine and glycine, and, on the contrary, increased the accumulation of tyrosine. Nitrogen rates have a significant effect on the maximal accumulation of valine, isoleucine, leucine, phenylalanine, histidine, cysteine and alanine and appeared as early as after the first increased rate of nitrogen (120 kg N/ha).
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Adeyeye, Emmanuel Ilesanmi. "Turkey-Hen Amino Acid Composition of Brain and Eyes". Biological Sciences - PJSIR 58, n.º 1 (27 de abril de 2015): 30–39. http://dx.doi.org/10.52763/pjsir.biol.sci.58.1.2015.30.39.
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The amino acids composition of the brain and eyes of the mature Turkey-hen (Meleagris gallopavo L.), were determined on dry weight basis. Total essential amino acids ranged from 35.1-36.0 g/100 g as 49.5-49.8% of the total amino acids. The amino acid score showed that lysine ranged from 0.76-0.91 (on whole hens egg comparison), 0.85-1.03 (on provisional essential amino acid scoring pattern), and 0.81-0.98 (on suggested requirement of the essential amino acid of a preschool child). The predicted protein efficiency ratio was 1.94-2.41, whilst essential amino acid index range was 1.06-1.08 and the calculated isoelectric point range was 3.97-4.18. The correlation coefficient (rxy) was positively high and significant at r = 0.01 for the total amino acids, amino acid scores (on the whole hens egg comparisons made) and the isoelectric point. On the whole, the eyes were better in 12/18 or 66.7% parameters of the amino acids than the brain of Turkey-Hen.
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Manulang, Benny, Sri Purwaningsih y Azrifitria Azrifitria. "Characteristics of Amino Acid, Fatty Acid and Mineral of Sea Hare". Jurnal Pengolahan Hasil Perikanan Indonesia 19, n.º 2 (30 de agosto de 2016): 168. http://dx.doi.org/10.17844/jphpi.v19i2.13224.
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Dolabella auricularia are found in the waters of Indo - Pacific and has active compound in health, which until now is still limited information about nutritional content from sea hare. The aim of this research were to determine morphometric and chemical characteristic D. auricularia which includes the proximate, amino acids, fatty acids and minerals. The composition of fatty acid were measured by gas chromatography (GC), amino acids were measured by high performanced liquid chromatography (HPLC), and mineral was measured by atomic absorption spectrophotometer (AAS). The sea hare contained 9 essential amino acids and 6 non essential amino acids. The highest essential amino acid was arginine (1.61%) while the highest non essential amino acids was glycine (3.02%). Sea hare contained 26 fatty acids such as saturated fatty acids 5.33%, monounsaturated fatty acids 2.11% and polyunsaturated fatty acids 4.10%. The high mineral was calcium 68100 mg/kg.
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Bröer, Stefan y Angelika Bröer. "Amino acid homeostasis and signalling in mammalian cells and organisms". Biochemical Journal 474, n.º 12 (25 de mayo de 2017): 1935–63. http://dx.doi.org/10.1042/bcj20160822.
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Cells have a constant turnover of proteins that recycle most amino acids over time. Net loss is mainly due to amino acid oxidation. Homeostasis is achieved through exchange of essential amino acids with non-essential amino acids and the transfer of amino groups from oxidised amino acids to amino acid biosynthesis. This homeostatic condition is maintained through an active mTORC1 complex. Under amino acid depletion, mTORC1 is inactivated. This increases the breakdown of cellular proteins through autophagy and reduces protein biosynthesis. The general control non-derepressable 2/ATF4 pathway may be activated in addition, resulting in transcription of genes involved in amino acid transport and biosynthesis of non-essential amino acids. Metabolism is autoregulated to minimise oxidation of amino acids. Systemic amino acid levels are also tightly regulated. Food intake briefly increases plasma amino acid levels, which stimulates insulin release and mTOR-dependent protein synthesis in muscle. Excess amino acids are oxidised, resulting in increased urea production. Short-term fasting does not result in depletion of plasma amino acids due to reduced protein synthesis and the onset of autophagy. Owing to the fact that half of all amino acids are essential, reduction in protein synthesis and amino acid oxidation are the only two measures to reduce amino acid demand. Long-term malnutrition causes depletion of plasma amino acids. The CNS appears to generate a protein-specific response upon amino acid depletion, resulting in avoidance of an inadequate diet. High protein levels, in contrast, contribute together with other nutrients to a reduction in food intake.
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Rasyid, Abdullah. "Amino Acid and Fatty Acid Compositions of Sea Cucumber Stichopus Vastus from Salemo Island Waters, Indonesia". Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 13, n.º 1 (31 de mayo de 2018): 9. http://dx.doi.org/10.15578/squalen.v13i1.285.
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Coastal waters of Indonesia have considerable biodiversity of sea cucumbers. In the present study the amino acid and fatty acid contents in sea cucumber Stichopus vastus collected from Salemo Island waters Indonesia were determined. Results showed that all essential and non-essential amino acids were found in S. vastus. The major essential amino acid content was arginine (28651.62 mg/Kg). Whereas the major non-essential amino acid content was glycine (60907.24 mg/Kg). The total fatty acids were determined in which finding suggested that saturated fatty acid was more than polyunsaturated fatty acid and monounsaturated fatty acid. The higher saturated fatty acid, polyunsaturated fatty acid and monounsaturated fatty acid were palmitic acid (0.07%), arachidonic acid (0.13%) and palmitoleic acid (0.03%) respectively.
Tesis sobre el tema "Essential amino acid"
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Nolte, Joubert van Eeden. "Essential amino acid requirements for growth in woolled sheep". Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/1666.
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Thesis (PhD(Agric) (Animal Sciences))--University of Stellenbosch, 2006.This project consisted of five studies. The objectives were to determine the essential amino acid (AA) requirements of growing woolled lambs (Merino and Dohne Merino) and the essential AA profile of duodenal digesta pre-dominantly derived from microbial protein. The limiting essential AA`s in high rumen degradable protein (RDP) diets to growing lambs, where microbial protein is the primary source of AA`s, were also identified. The first study determined the essential AA profile of duodenal protein on a high rumen degradable diet and evaluated the impact of dietary RDP concentration and source [true RDP vs. non-protein nitrogen (NPN)] on the AA composition of supplied in the duodenum. The first trial in this study evaluated the effects of increasing true RDP levels on the essential AA composition of duodenal protein primarily derived from rumen microbes. The lambs had free access to wheat straw and fresh water. The daily RDP supplements were administered in two equal doses into the rumens through rumen cannulas at 07:00 and 19:00. Duodenal digesta was extracted with 6h intervals through T-type cannulas, inserted proximally to the common bile duct. Sampling time was advanced 2h every day to obtain duodenal samples on every even hour of a 24h period after three days. As expected, deficient RDP limited the supply of essential AA`s in the iv duodenum. When the true RDP supplements increased, the duodenal flow of essential AA`s also increased concomitantly, but appeared to level off at the higher RDP levels. Despite the positive quantitative effects of true RDP supplementation on AA supply to the duodenum, the AA profile in the duodenum was unaltered. Consequently, the essential AA profile of duodenal protein of sheep receiving high RDP diets, where microbial protein is the primary source of AA`s in the duodenum, is relatively constant and insensitive to dietary RDP concentration. In the second trial the effects of RDP source (true RDP vs. NPN) on the essential AA profile of duodenal protein on high RDP diets were evaluated by substituting increasing amounts of urea for true RDP in isonitrogenous teatments. Higher NPN increments reduced the daily supply of essential AA`s in the duodenum. In corroboration of the first trial, the AA profile of the duodenal protein was very constant, irrespective of the RDP source. Since microbial protein is the major source of duodenal AA`s on high RDP diets, this study supports the view that microbial protein has a relatively constant AA profile, but microbial protein yield varies according to several rate limiting factors in the rumen. A constant microbial AA profile allows accurate estimates of microbial essential AA supply in the small intestine if microbial protein production and fluid and particulate outflow rates from the rumen can be accurately predicted. This allows the development of more accurate undegradable protein (UDP) supplementation strategies, based on the essential AA requirements of animals. In the second study growing male Merino and Dohne Merino lambs were slaughtered at different weights and body condition scores. The digesta was removed from the stomachs and intestines and every organ or body part were weighed to determine the whole empty body (WEB) composition. The WEB was partitioned into the carcass, internall offal (stomachs, intestines, organs and blood) and external offal (head, feet, skin and wool). No differences were apparent in the proportional weight distribution of similar body components of the same breed at different ages. In a comparison between breeds, the proportional weight contributions of the carcasses from both breeds to the WEB weight were remarkably similar at both slaughtering stages. The Dohne Merino lambs had proportionally larger internal offals and smaller external offals than the Merino lambs at both slaughters. Unless the essential amino acid compositions of the internal and external offals were identical to the carcass, the dissimilarities in weight and protein allocation to these two components within the WEB`s of Merino and Dohne Merino lambs imply a distinct WEB essential AA composition for each breed. The apparent digestibilities of dry matter (DM), crude protein (CP), energy, acid detergent fibre (ADF), neutral detergent fibre (NDF), fat and ash did not differ between Merino and Dohne Merino lambs. Energy retention was also similar for the two breeds, but the Merino lambs retained considerably more N than the Dohne Merino lambs. This may also impact on the respective amino acid requirements of the lambs. Since the Merino lambs utilise N more efficiently, they may have potentially lower essential amino acid requirements to achieve a similar growth rate. The WEB essential AA compositions of growing Merino and Dohne Merino lambs were determined in the third study. Based on the ideal protein concept, the WEB essential AA profile was accepted as representative of the AA requirements for growth. The use of a single body part as a representation of the WEB AA profile was also evaluated. Differences in the proportional weight and protein contribution of the three body components (carcass, internal offal and external offal) of the two breeds strongly suggested that the WEB AA composition of the breeds would differ, because of likely differences in the AA profiles of these components. The essential AA profiles of the carcasses from the two breeds were surprisingly similar. However, the essential AA compositions of the internal offal and external offal differed substantially from each other, as well as from the carcass. In addition, the internal offal and external offals of each breed had characteristic essential AA profiles. Inevitably, the WEB essential AA profiles of Merino and Dohne Merino lambs differed considerably. Only the leucine and phenylalanine concentrations in the WEB`s of Merino and Dohne Merino lambs did not differ. Significant differences in the concentrations of eight essential AA`s implied that the two breeds have different AA requirements for growth. The different AA compositions of the internal and external offal within each breed also illustrated that the use of a single body component, like the carcass, as a predictor of WEB essential AA composition contains considerable inaccuracies. The essential AA index indicated that the duodenal protein, primarily derived from rumen microbes, provided approximately 81 % of the qualitative AA requirements of growing lambs. During periods of sufficient availability of very low-quality forage, as the diet in this study simulated, microbial protein is not able to support maximum growth. The first two limiting AA`s (histidine and methionine) could not even support daily growth rates of 100 g/d. This is very low and stresses the need for effective undegradable AA supplementation under these conditions. Chemical scores identified histidine as the first limiting AA in high RDP diets (predominantly microbial protein), followed by methionine, leucine, arginine and phenylalanine. However, the requirements for histidine and arginine are frequently over estimated and these AA`s should actually be considered semi-essential, which could render methionine, leucine and phenylalanine the first three limiting AA`s to growing lambs receiving high RDP diets. Because of the limitations of static measurement systems for the determination of AA requirements, a more comprehensive evaluation method was introduced for determination of the limiting AA`s in duodenal protein of lambs on high RDP diets, in the fourth study. The fourth study focused on the identification of limiting AA`s to growing lambs being limit-fed a high RDP diet. The diet consisted primarily of soybean hulls, for its’ low rumen UDP content. Microbial protein production was calculated as 13 % of total digestible nutrient intake and complementary AA supplements prepared to simulate the WEB AA profile, determined in the previous study, in the small intestine. To eliminate the influence of the rumen on the AA supplements, the latter were infused into the abomasums via flexible tubing. Each essential AA was in turn removed from the control treatment (simulating the WEB composition) and the effect on N retention measured. When methionine or the branched-chain amino acids (BCAA`s) were removed from the infusate, N retention of the lambs was reduced. Consequently, methionine and at least one of the BCAA`s limited growth performance of young lambs when microbial protein was the predominant source of AA`s. The concomitant increased plasma concentrations of total AA`s when methionine or the BCAA`s were removed from the infusate corroborates the effects on N retention, since it indicates that AA utilisation was reduced when these AA imbalances were introduced. Amino acid imbalances had no effect on apparent DM, organic matter (OM) or NDF digestion, but N digestibility was reduced. The final study verified whether the BCAA’s were co-limiting the growth of lambs, or if any single BCAA was responsible for the limitation. Again the WEB AA profile of growing lambs was simulated in the small intestine via abomasal infusions to lambs receiving a soybean hull-based diet. Leucine, isoleucine and valine were individually or simultaneously removed from the infusate and the impact on N retention measured. On an individual basis valine had the largest negative impact on the efficiency of N utilisation. However, the simultaneous removal of the BCAA`s resulted in the lowest N retention, suggesting that valine might be limiting, but the three BCAA`s are more likely to be co-limiting in diets to growing lambs where microbial protein is the primary source of AA`s. Once again, neither DM, OM or NDF digestibility were affected by the AA imbalances. Nitrogen digestibility was, however, negatively affected by AA imbalances. This project succeeded in establishing the essential AA profile of duodenal protein in sheep receiving high RDP diets. The WEB essential AA compositions of growing lambs from two prominent sheep breeds in South Afica were then determined and the duodenal essential AA profile evaluated against the calculated AA requirements. Finally, the AA`s that limit growth in diets where microbial protein is the predominant source thereof were identified. These results contribute to the current knowledge of AA requirements in growing lambs, and highlight areas for future research, as discussed in the General Conclusion.
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Erasmus, Morné. "Amino acid requirements of feedlot cattle according to the duodenal and whole empty body essential amino acid profile". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52085.
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Thesis (MScAgric)--University of Stellenbosch, 2001.ENGLISH ABSTRACT: The purpose of this study was to determine the essential amino acid requirements of beef cattle under feedlot conditions through evaluation of the duodenal and whole empty body essential amino acid compositions. To define the ideal protein required for growth, the whole empty body essential amino acid compositions of 8 beef steers (Simmental and Hereford crosses) was investigated. The amino acid composition of the components (carcass, metabolic organs and residual fraction), was pooled relative to their respective mass and protein contribution, resulting in the calculated whole empty body amino acid composition: arginine 6.81; histidine 2.69; isoleucine 4.02; leucine 6.96; lysine 7.43; methionine 2.01; phenylalanine 4.03; threonine 4.01; valine 5.30; tryptophan 0.82. Variations in profiles were found between scientific reports, either indicating that ratios change with growth and implants or possibly through genotype. The present study's body amino acid ratios were used to estimate dietary amino acid requirements through evaluation of the duodenal essential amino acid compositions from three different maize based feedlot diets. Although there was a general increase in the biological value of protein after rumen fermentation, the duodenal essential amino acids in comparison with the whole empty body recorded deficient/unbalanced profiles of essential amino acids for growth. The chemical scores suggested that the first-to-thirdlimiting amino acids in the duodenal digesta of beef cattle, that received three different commercially available feedlot diets, were: histidine, lysine, methionine/arginine (Diet 1), histidine, arginine, lysine (Diet 2) and arginine, methionine, histidine (Diet 3). Thedisproportionate duodenal amino acid concentrations obtained from the three diets, emphasise the necessity to enhance the intestinal delivery of amino acid profiles through different undegradable protein sources, with the objective to maximise protein utilisation and obtain the genetic potential for optimal growth in feedlot cattle. When amino acid requirements and flows to the duodenum were simulated using the Cornell Net Carbohydrate and Protein system (CNCPS), predictions indicated that lysine amino acid flow was limiting the metabolizable allowable average daily gain in Diet 1 and 3. Predicted profiles indicated that the order of limitation was: lysine, arginine, histidine (Diet 1), lysine, arginine, histidine, methionine (Diet 2) and lysine, arginine, histidine (Diet 3). The predicted profiles were in accordance with observed duodenal values, except for methionine that was observed limiting in Diet 1 and 3; however, the sequence and extent of limitation varied. Results indicate that prediction models have potential in predicting requirements; however there are still limitations for use to accurately define requirements for particular EAA's. From the present study, it is clear that the protein accretion was constrained by quantity and/or disproportionality of amino acids available for absorption. Further research should therefore be directed towards obtaining a more desirable array of amino acids to the lower digestive tract that is digestible, absorbable and an economically viable option for the feedlot operator.
AFRIKAANSE OPSOMMING: Aminosuurbehoeftes van Voerkraalbeeste Volgens die Duodenale en Totale Lee Liggaam Essensiele Aminosuur Profiel: Die doel van hierdie studie was om die essensiele aminosuur vereistes van vleisbeeste onder voerkraal toestande te bepaal deur die evaluering van die duodenale en totale lee liggaam essensiele aminosuursamesteilings. Om die idea Ie proteiene wat vir groei benodig word te definieer, is 'n ondersoek ingestel na die totale lee liggaam essensiele aminosuursamesteilings van 8 vleisbees osse (Simmetailer en Hereford kruise). Die aminosuursamesteiling van die komponente (karkas, metaboliese organe en residuele fraksie), se massa en proteien bydrae is gebruik om die totale lee liggaam aminosuursamestelling 5005 volg te bereken: arginien 6.81; histidien 2.69; isoleusien 4.02; leusien 6.96; lisien 7.43; metionien 2.01; fenielalanien 4.03; treonien 4.01; valien 5.3; triptofaan 0.82. Variasies in profiele tussen wetenskaplike verslae is gevind. Dit dui daarop dat groei en inplantings of moontlik genotipe 'n invloed op profiele kan he. Die huidige studie se liggaam aminosuurverhoudings is gebruik om die dieet aminosuurbehoeftes te skat deur evaluering van die duodenale essensiele aminosuursamesteilings van drie verskiilende mielie-gebaseerde voerkraal diete. Alhoewel daar 'n algemene toe name in die biologiese waarde van die proteien na rumen fermentasie was, het die duodenale essensiele aminosure in vergelyking met die totale lee liggaam, ongebalanseerde profiele van essensiele aminosure vir groei getoon. Die chemiese teilings toon aan dat die eerste-tot-derde-beperkende aminosure in die duodenale inhoud van vleisbeeste wat drie verskillende kommersieel beskikbare voerkraal diete ontvang het, soos volg is: histidien, lisien, metionieniarginien (Dieet 1), histidien, arginien, lisien (Dieet 2) en arginien, metionien, histidien (Dieet 3). Die ongebalanseerde aminosuur konsentrasies wat in die duodenum van die drie dlete verkry is, beklemtoon die noodsaaklikheid om die intestinale lewering van aminosuurprofiele te verbeter deur verskillende nie-degradeerbare proteien bronne te voer. Die doelwit moet wees om proteien verbruik te optimaliseer en daardeur die genetiese potensiaal vir optimale groei in voerkraalbeeste te bereik. Met die simulering van aminosuurbehoeftes en vloei na die duodenum van die drie standaard voerkraal diete met behulp van die "Cornell Net Carbohydrate and Protein System" (CNCPS), het voorspellings gewys dat lisien aminosuurvloei die metaboliseerbare toelaatbare gemiddelde daaglikse toename in Dieet 1 en 3 beperk het. Voorspelde profiele wys dat die volgorde van beperking soos volg sou wees: lisien, arginien, histidien (Dieet 1), lisien, arginien, histidien, metionien (Dieet 2)' en lisien arginien, histidien (Dieet 3). Die voorspelde profiele was in ooreenstemming met die waargeneemde duodenale waardes, behalwe vir metionien wat beperkend was in Dieet 1 en 3; die volgorde en mate van beperking was egter verskillend. Resultate wys dat voorspellingsmodelle die potensiaal het om behoeftes te voorspel. Vir die akkurate definisie van behoeftes vir spesifieke essensiele aminosuure is daar egter nog beperkinge. Uit die huidige studie, is dit duidelik dat protetenneerleqqinq deur die hoeveelheid en/of oneweredigheid van geabsorbeerde aminosure beperk is. Verdere navorsing moet dus fokus op die verkryging van In meer geskikte profiel van aminosure wat verteerbaar, opneembaar en 'n ekonomiese lewensvatbare opsie vir die voerkraalbestuurder is.
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Jurgens, Andre Hendrik. "Feedlot performance and essential amino acid growth requirements of Dorper lambs". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52846.
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Thesis (MScAgric)--University of Stellenbosch, 2002.ENGLISH ABSTRACT: The Dorper is numerically the second most abundent of all the sheep breeds in South Africa. It is the most numerous sheep breed in the dry arid areas of South Africa which make out a very big portion of the natural grazing in South Africa. In this study the feedlot performance was specifically investigated since so little research has been done in this regard. In the first study (Chapter 1), the production efficiency, body components and commercial yield of 13 Dorper and 12 Merino lambs were investigated. A pelleted diet was fed ad lib and the water intake per day was measured. Lambs were slaughtered at 30kg and at 40kg live weight and cut up according to the South African commercial cuts. The weights of the organs, head, feet, skin and carcass were also recorded. Results from the first study showed that Dorpers had a lower (P<0.05) water efficiency (285.97 mVkgO75/day) than the Merinos (240.07 mVkg075/day), but had a higher (P<0.05) nitrogen retention. The head, feet, skin, heart, lungs, kidneys and diaphragm of Merino lambs were heavier (P<0.05). Merinos had heavier (P<0.05) breast and shank and thick rib (only at 40kg live weight) cuts. But the Dorper had a significantly heavier hindquarter (buttock and loin) which is the high-priced cut of any carcass. It seems that the Dorper will do well under feedlot conditions, and would possibly make a better commercial meat producer than the Merino under all circumstances. In the second study (Chapter 2), the free-ranging Dorper on natural grazing were compared with 7 Dorper lambs in the feedlot study. The essential amino acids in the duodenal contents were compared. The free-ranging Dorpers were randomly slaughtered at 40 kg live weight and a duodenal sample was collected. The feedlot Dorpers were also slaughtered at 40 kg live weight and a duodenal sample was taken. The second study indicated no significant differences between the EAA composition of the duodenal samples, whether protein quantity was taken into account (gAA/100g crude protein (CP)) or not (expressed as % of lysine). The chemical scores indicated that the two most limiting amino acids in the duodenal digesta for whole empty body growth were: arginine and histidine. Excess levels of amino acids tend to be present in all three duodenal digesta samples (isoleucine, leucine, lusine, methionine, phenylalaline, threonine and valine). The whole empty body EAA composition (g AA/100 g crude protein) was as follows 7.10 arginine; 2.40 histidine; 3.31 isoleucine; 7.22 leucine; 6.61 lysine; 1.62 methionine; 3.91 phenylalanine; 3.77 threonine and 4.85 valine. The composition can serve as an example of the ideal EAA requirements for whole empty body growth between 30 and 40 kg live weight of Dorper ram lambs. The duodenal amino acid concentrations of the free-ranging Dorper compared well with those of the feedlot Dorpers which suggests that the microbial organisms have a big influence on the amino acid concentration which reaches the intestines.
AFRIKAANSE OPSOMMING: Die voerkraal prestasie en essentiele aminosuur behoeftes van groeiende Dorper lammers: The Dorper is getalgewys die tweede mees talryke skaapras in Suid-Afrika. Dit is die mees talryke skaapras wat in die drce woestynagtige gebiede van Suid-Afrika aangetref word. Die gebiede beslaan die grootste oppervlakte van Suid-Afrika se natuurlike weiveld. In die studie is voerkraal prestasie van die Dorper nagevors, spesifiek omdat daar so min navorsing op hierdie gebied gedoen is. In die eerste studie (Hoofstuk 1) is die produksie doeltreffendheid, liggaams komponente en kornrnersiele produksie van 13 Dorper- en 12 Merino lammers ondersoek. 'n Verpilde rantsoen is ad lib gevoer en die water inname per dag is ook gekontroleer. Die lammers is geslag op 30 en 40 kg lewende gewig en die karkasse is daarna opgesny volgens die Suid-Afrikaanse kornmersiele karkassnitte. Die resultate van die eerste studie het getoon dat Dorpers 'n laer water potentiaal (P<0.05) (285 97 mflkgO 75/dag) as die Merinos (240.07 mVkg075/dag) het. Dorper lammers het ook 'n hoer (P<0.05) stikstof retensie. Die kop, vel, pote, hart, longe, niere en diafragma van Merino lammers was swaarder (P<0.05). Merinos se brisket en dikrib snitte weeg ook swaarder (P<0.05). Die Dorper het 'n beduidende swaarder agterkwart (len de en boud) gehad, wat die duurste snit is van enige karkas. Die Dorper het baie goed gedoen in die voerkraal toestande en sal waarskynlik onder aile omstandighede 'n hcer vleisproduksie op die Merino lewer. In die tweede studie (Hoofstuk 2), is die vryweiende Dopers op natuurlike weiding vergelyk met die Dorpers in 'n voerkraal. Die twee groepe Dorpers se essensiele aminosuur samestelling in hul dunderms is bepaal en vergelyk om te bepaal of daar enige tekorte teenwoordig is. Die Dorpers in die veld en in die voerkraal is op 40 kg lewende gewig geslag en monsters van die dunderm inhoud is gekollekteer. Die monsters is ontleed om te bepaal of daar enige betekenisvolle verskille in die essensiele aminosure van die dunderm inhoud tussen die veld Dorpers en voerkraal Dorpers was. Die tweede studie het geen betekenisvolle verskille getoon tussen die dunderm monsters se essensiele aminosure, of die hoeveelheid proteien (gAA/100g) in aanmerking geneem is of nie (uitgedruk as % lisien). Die chemiese telling dui aan dat die twee mees beperkende aminosure in die dunderm inhoud vir lee liggaam groei arginien en histidien was. Oormaat vlakke van aminosure kom voor in al drie dunderm inhoud monsters (isoleusien, leusien, lisien, metionien, femielalanien, treonien en valien). Die totale lee liggaam essensiele aminosuursamestelling (g aminosuur/100g ruprotein) was soos volg: 7.10 arginien; 2.40 histidien; 3.31 isoleusien; 7.22 leusien; 6.61 lisien; 1.62 metionien; 3.91 fenielalanien; 3.77 treonien en 4.85 valien. Hierdie aminosuursamestelling kan as 'n aanduiding dien vir die ideale aminosuurbehoeftes van Dorper ram lammers vir totale lee liggaamsgroei vanaf 30 tot 40 kg lewende massa. Die dunderm aminosuur konsentrasie van die Dorper in die veld stem goed ooreen met die van die voerkraal Dorper. Dit toon waarskynlik dat die mikrobe organismes in die rumen In groot invloed het op die aminosuur samestelling wat die dunderm bereik.
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Myers, Adelyn. "Modeling post absorptive amino acid metabolism in dairy cattle". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/95890.
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The purpose of this research was to evaluate four objectives: 1) update and evaluate predictions of essential amino acid (EAA) outflows from the rumen, 2) predict EAA use and release by the portal drained viscera (PDV) and liver (LIV) of dairy cows, 3) predict EAA use by the mammary (MAM) and non-splanchnic, non-mammary (OTH) tissues, and 4) predict milk protein production from MAM use. To evaluate the first objective, a model was constructed using previously derived equations for ruminally undegraded (RUP), microbial (MiP) and endogenous protein (EndP) flow from the rumen and refit to literature data. Corrections were included in the model to address recovery of EAA during 24-h acid hydrolysis. Upon initial evaluation, all EAA, except Leu, were over predicted and slope bias (P < 0.01) was present for all except Met and Leu. Because of the bias, residuals were regressed on the EAA from each protein flow and adjustments were made to the protein flows. The added adjustments removed all mean bias for the EAA; however, a small slope bias was introduced for Lys and Thr. To evaluate the second objective, equations of Hanigan et al. (2004b) were tested and modifications were made to determine which equation form best represented EAA use by the tissue. Upon initial evaluation of the PDV model of Hanigan et al. (2004b), significant slope bias was present and addressed by deriving alternative forms of the equation. Initial predicted EAA use displayed a mean bias ranging from 0.15 to 45 % and a slope bias ranging from 0.02 to 76% mean square error. The alternative equation forms derived reduced the overall mean and slope bias and improved other fit statistics (RMSE, CCC). To evaluate the third objective, previously derived equations from Hanigan et al. (1998b) were tested using literature data and modifications were made to address deficiencies for each EAA. Upon initial evaluation of the MAM model, significant mean and slope bias was present and was further addressed by derivation of alternative equation forms. Initial evaluation of the OTH model displayed significant mean and slope bias for majority of the EAA ranging from 0.3 to 26 % for mean and 46 to 61 % for slope. For the last objective, several models, both linear and non-linear were evaluated to determine which EAA have a significant impact on milk protein. All models derived has prediction errors below 18-20 % which is comparable or a s light improvement as compared to previous literature data (Moraes et al., 2018). Overall, the equations evaluated show promise in accurately predicting dietary EAA from the time of absorption to their use within the tissues (PDV, LIV, MAM, and OTH) and further impact on milk protein production.
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Van, Zyl Liana. "The essential amino acid requirements of springbok, blesbok and impala for optimal growth". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52524.
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Thesis (MScAgric)--University of Stellenbosch, 2001.ENGLISH ABSTRACT: Regardless of the extensive game eradication during most of the previous century, the game farming industry in South Africa has shown dynamic growth over the past few decades. Currently the approximately 8 000 game farms have a total income of more than R850 million per annum. Although there are various game species included in these farming enterprises, three of the most important species for commercial farming and meat marketing are springbok iAntidorcas marsupialisï, blesbok (Damaliscus dorcas phillipsiï and impala (Aepyceros melampus). Since nutrition is a key factor in the productivity of animals, any information on this subject is essential for the successful management of a game farm. However, apart from the general lack in applied research on game animals (due to the different approaches by biologists and agricultural researchers), there is also only limited information available on the nutritional requirements of game species or any of the aspects affected by nutrition. In order to address the above shortcomings in game animal nutrition, two separate studies were conducted. The purpose of the first study was to determine the physical body component and nitrogen (N) distribution in the springbok, blesbok and impala. The chemical composition of the three-rib cut was also compared with that of the carcass. Amino acid requirements for growth of the three game species were investigated in the second study according to the ideal protein concept. The essential amino acid (EAA) profile of the whole empty body of the three game species was compared with the EAA profile of the duodenal digesta in order to detect any imbalances for optimal growth. The same animals were used in both studies, namely eight of each of the three game species. Characterization of the physical body composition revealed that the dressing percentages (% of body weight; % of empty body weight) for the three game species were: springbok (57.1 ± 2.4 %; 64.0 ± 2.5 %), blesbok (50.2 ± 2.1 %; 62.8 ± 1.4 %) and impala (57.4 ± 2.2 %; 65.6 ± 2.0 %). The proportional distribution ofN between the carcass, external offal and internal offal was also determined. The mean carcass N concentration of the impala was higher (P<0.05) than that of the springbok and blesbok on a dry matter basis. According to the carcass chemical composition, the three game species seem to have a better potential for lean meat production (fat content of carcass 4.7-5.2 %) than domestic sheep (17-25 % fat). Male animals had a lower (P<0.05) fat and higher (P<0.05) moisture percentage in the carcass and threerib cut than the females. The fat correlation between the three-rib cut and the carcass on both an as-is and dry matter basis was significant across species and sexes. The protein content of the same cuts did, however, not yield a significant correlation on an as-is basis, and only the protein content of the springbok three-rib cut related (P<0.05) to that in the carcass on a dry matter basis. The second study concentrated on the nutritional requirements of springbok, blesbok and impala, and more specifically the EAA requirements. Differences (P<0.05) were found between the whole empty body EAA composition of the three game species. These differences were present whether protein quantity was included in the calculations (g AA/100 g crude protein) or not (expressed as % of lysine). The chemical scores indicated that the four most limiting amino acids (three for impala) in the duodenal digesta for whole empty body growth were: arginine, histidine, threonine and methionine (springbok); methionine, arginine, histidine and lysine (blesbok); and methionine, histidine and arginine (impala). Further disproportion of the amino acids in the duodenal digesta was present in excess levels of isoleucine (blesbok) and lysine, valine, leucine, threonine, isoleucine and phenylalanine (impala). The EAA:Lysine ratios of the whole empty body indicated a similar trend for the three game species.
AFRIKAANSE OPSOMMING: Die essensiële aminosuurbenodighede van springbok, blesbok en rooibok vir optimale groei: Ten spyte van die feit dat wild grootskaals uitgedun is gedurende die vorige eeu, het die wildboerdery-bedryf in Suid-Afrika oor die laaste paar dekades dinamiese groei getoon. Die totale inkomste van die ongeveer 8000 wildsplase beloop tans meer as R850 miljoen per jaar. Alhoewel daar verskeie wildspesies is wat by hierdie tipe boerdery ingesluit word, is die springbok (Antidorcas marsupialis), blesbok (Damaliscus dorcas phillipsi) en rooibok (Aepyceros melampus) van die belangrikste spesies vir kommersiële boerdery en vleisbemarking. Voeding IS 'n sleutelfaktor in die produktiwitieit van diere en daarom is emge inligting oor hierdie onderwerp noodsaaklik vir die suksesvolle bestuur van 'n wildsplaas. Afgesien van die algemene tekort aan toegepaste navorsing op wilde diere (as gevolg van die verskillende benaderings van bioloë en landboukundige navorsers), is daar ook slegs beperkte inligting beskikbaar oor die voedingsbehoeftes van wilde dierspesies of enige van die faktore wat deur voeding beïnvloed word. In 'n poging om bogenoemde tekortkominge in die voeding van wilde diere aan te spreek, is daar twee aparte studies uitgevoer. Die doel van die eerste studie was om die fisiese liggaamsamestelling en die stikstof (N) verspreiding in die springbok, blesbok en rooibok te bepaal. Die chemiese samestelling van die drie-ribsnit is ook met die van die karkas vergelyk. In die tweede studie is ondersoek ingestel na die aminosuurbehoeftes van die drie wildspesies deur van die ideale proteïen konsep gebruik te maak. Die bepaling van die essensiële aminosuurprofiel van die totale leë liggaam van die onderskeie drie wildspesies is bepaal en met die essensiële aminosuurprofiel van die duodenale-inhoud vergelyk, ten einde enige wanbalans vir optimale groei vas te stel. Dieselfde diere is in beide studies gebruik, naamlik ag springbokke, blesbokke en rooibokke. 'n Beskrywing van die fisiese liggaamsamestelling het aangetoon dat die uitslagpersentasies (% van liggaamsmassa; % van leë liggaamsmassa) van die drie wildspesies as volg was: springbok (57.1 ± 2.4 %; 64.0 ± 2.5 %), blesbok (50.2 ± 2.1 %; 62.8 ± 1.4 %) en rooibok (57.4 ± 2.2 %; 65.6 ± 2.0 %). Die proporsionele verspreiding van N in die karkas, uitwendige afval en inwendige afval is ook bepaal. Die gemiddelde N konsentrasie in die karkas van die rooibok was hoër (P<0.05) as die van die springbok en blesbok op 'n droë materiaal basis. Dit blyk vanaf die chemiese samestelling van die karkas dat die drie wildspesies 'n groter potensiaal het vir die produksie van maer vleis (vet-inhoud van karkas 4.7-5.2 %) as skape (17-25 % vet). Manlike diere het 'n laer (P<0.05) vetpersentasie en 'n hoër (P<0.05) vogpersentasie in beide die karkas en die drie-ribsnit teenoor die vroulike diere gehad. 'n Betekenisvolle korrelasie is tussen die persentasie vet in die drie-ribsnit en die karkas van al drie wildspesies en vir beide geslagte gevind, op beide 'n nat en droë materiaal basis. Die proteïeninhoud van dieselfde snitte was egter nie op 'n nat basis betekenisvol gekorreleerd nie, en slegs die proteïen-inhoud van die springbok se drieribsnit het verband gehou (P<0.05) met die in die karkas op 'n droë materiaal basis. Die klem van die tweede studie was op die voedingsbehoeftes van springbok, blesbok en rooibok, en meer spesifiek die essensiële aminosuurbenodighede. Daar is verskille (P<0.05) tussen die totale leë liggaam essensiële aminosuursamestelling van die drie wildspesies gevind. Hierdie verskille was aanwesig afgesien daarvan of die hoeveelheid proteïen in berekening gebring is (g aminosure /100 g ruproteïen) of nie (uitgedruk as % van lisien). Volgens die chemiese tellings was die vier mees beperkende aminosure (drie vir rooibok) in die duodenale-inhoud vir totale leë liggaamsgroei as volg: arginien, histidien, treonien en metionien (springbok); metionien, arginien, histidien en lisien (blesbok); en metionien, histidien en arginien (rooibok). Verdere wanbalanse in die armnosure van die duodenale-inhoud was aanwesig in die oormaat isoleusien (blesbok) en lisien, valien, leusien, treonien, isoleusien en fenielalanien (rooibok). Die verhouding van die essensiële aminosure tot lisien van die totale leë liggaam het by al drie wildspesies dieselfde tendens getoon.
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Arriola, Apelo Sebastian Ignacio. "Essential Amino Acid Regulation of Cell Signaling and Casein Synthesis in Mammary Tissue". Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/24866.
Texto completoResumen
Specific AA have been demonstrated to activate signaling pathways that regulatetranslation initiation and to stimulate protein synthesis in mammary tissue. The
objectives of this research were to determine the response to Ile, Leu, Met, and Thr in
cellular signaling and "-S1 casein fractional synthesis rates (CFSR). An experiment was
developed as a composite design. The experiment was replicated in tissue corresponding
to 5 cows. Mammary tissue slices (0.12 ± 0.02 g) from lactating dairy cows were
incubated 4 h in treatment media enriched with 2H5 Phe. Following incubation, slices
were homogenized in lysis buffer and caseins were precipitated by acidification to pH
4.6. An aliquot of the pellet was trypsinized and 2H5 Phe enrichment in the 34-
NLLRFFVAPFPE-45 peptide of "-S1 casein was measured by MALDI TOF-MS and
used to determine CFSR (%/h). Western immunoblotting was performed to identify total
and site-specific phosphorylated mammalian target of rapamycin (mTOR, Ser2448),
eukaryotic elongation factor (eEF) 2 (Thr56), ribosomal protein (rp) S6 (Ser235/236),
and eukaryotic initiation factor (eIF) 2" (Ser51). Addition of Ile, Leu, Met, or Thr had
no effect on eIF2" phosphorylation. Isoleucine positively affected mTOR, and rpS6, and
negatively affected eEF2 phosphorylation. Leu had a similar effect on eEF2, but not on
mTOR or rpS6, and these two AA inhibited each other. Thr negatively interacted with
Ile on mTOR and rpS6, and with Leu on eEF2. Increasing concentrations of Ile, Leu,
Met, and Thr caused curvilinear increases in CFSR. The maximum response to Ile, Leu,
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Met, and Thr was at 71, 49, 60, and 65% of DMEM concentrations, respectively. All
maximums were above plasma AA concentrations observed in lactating cows fed to meet
NRC requirements. The CFSR estimated at those maximums were similar between AA
(3.6 ± 0.6 %/h). Individual AA effects on CFSR did not correlate with mTOR signaling.
Independent CFSR responses to individual essential AA observed in this study contradict
the single-limiting AA theory assumed in current requirement systems. The saturable
responses of CFSR to these 4 AA also demonstrate the deficiencies of a fixed postabsorptive
AA efficiency approach for determining AA requirements for milk protein
synthesis.
Ph. D.
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Ichiryu, Naoki. "Essential amino acid depletion by embryonic stem cells as a mechanism of immune privilege". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:68fe0c58-03d2-4ba0-af62-461a04a3e9d6.
Texto completoResumen
Mouse embryonic stem cells (ESCs) are capable of differentiating into any somatic cell type and are known to display fragile immune privilege in vivo and in vitro. The extent to which the depletion of essential amino acids (EAAs) by ESCs contributes to this phenomenon was investigated. ESCs were found to express various enzymes capable of catabolising EAAs within the culture medium. In particular, depletion of threonine, valine and lysine was found to have significant impact on T cell proliferation and differentiation, biasing their polarisation towards a FoxP3+ T regulatory (Treg) phenotype. Supplementing ESC conditioned medium with these three EAAs alone rescued normal T cell proliferation, whereas artificially limiting their availability was sufficient to induce Treg cell differentiation to a level equivalent to general EAA depletion. The pattern of EAA catabolism by mouse ESC was shared by induced pluripotent stem cells, while mouse melanoma cell lines and human ESCs displayed distinct patterns of EAA depletion. The cytosolic branched chain aminotransferase enzyme, Bcat1, catalyses the first step of branched chain amino acid catabolism (isoleucine, leucine and valine), and is highly expressed by both mouse and human ESCs. The contribution of this enzyme to the establishment of acquired immune privilege by ESC-derived tissues was, therefore, investigated. ESC lines were derived from mice lacking Bcat1 activity and were characterised. Bcat1−/− ESC lines displayed no difference to their wildtype counterparts (Bcat1LoxP) in terms of in vitro proliferation and their capacity to form teratomas in vivo. Furthermore, the loss of Bcat1 function had little impact on the inhibition of T cell proliferation in culture, ability to induce Treg cell commitment or their ability to prevent rejection by T cell receptor transgenic recipients, suggesting the minimal contribution of Bcat1 to the depletion of EAAs by ESCs. In conclusion, EAA depletion by mouse ESC may provide a mechanistic explanation for the previously described immune-suppressive capacity of ESC.
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Ahrens, Katharina Maria. "Identification of amino acid residues essential for the catalytic activity of Drosophila P element transposase". [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=959520686.
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Huang, Xinbei. "Assessing Availability and Utilization of Essential Amino Acids in Dairy Cattle Using Stable Isotope Based Approach". Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/104633.
Texto completoResumen
Determining the AA availability and metabolism in ruminant is a big challenge due to the rumen fermentation and complicated post absorption utilization. Current techniques used for direct determination of AA absorption and metabolism are laborious and expensive with large variation. The objectives of this project were to investigate AA availability of rumen undegradable protein, develop a stable isotope technique for determination of microbial protein and to evaluate the metabolism of amino acids in mammary glands of dairy cattle using stable isotope-based approaches. In the first experiment, seven heifers (258 ± 28 kg BW) were randomly chosen and assigned to 8 treatment sequences in a 7 x 8, incomplete, Latin square design. Treatments were a basal diet (BD), and 10% (DM basis) of BD replaced by corn silage (CS), grass hay (GH), alfalfa hay (AH), dried distillers grain (DDGS), soybean hulls (SH), wet brewers grain (BG), or corn grain (CG). Individual essential AA availabilities for corn silage, grass hay, alfalfa hay, dried distillers grain, soyhulls, brewers grain and corn grain were 33.4, 29.9, 34.1, 40.6, 28.8, 41.2, and 36.5% of the essential AA in each of the respective ingredients when a loss of 8.27% to splanchnic utilization during first pass was assumed; however, availability varied across individual essential AA. In the second experiment, twelve cows were blocked into 3 groups according to days in milk and randomly assigned to 4 treatments in a repeated 4 x 4 Latin square design with 2 factors to evaluate the essential AA availability from microbial protein and rumen undegradable protein under different rumen fermentation conditions. The 4 treatments were high rumen undegradable protein and high starch (HPHS), low rumen undegradable protein and high starch (LPHS), high rumen undegradable protein and low starch (HPLS) and low rumen undegradable protein and low starch (LPLS). Microbial protein synthesis calculated from purine derivatives was positively associated with rumen degradable protein, which was consistent with total microbial AA entry derived from the isotope dilution model indicating that the isotope based approach was representative. The individual essential AA availability from microbial protein was determined by isotope technique, whereas the PD method was just total PD absorption reflecting CP absorption. The metabolizable AA estimates from NDS nutritional model was similar to results from isotope dilution models, but with smaller difference among treatments. The microbial protein estimated from White's model showed the same trend among treatments compared to isotope dilution model, which may imply it represents the rumen fermentation better. The average essential AA digestibility for microbial AA was 82%, which varied across individual AA and treatments. In the third experiment, four cows (78 ± 10 DIM) were used to study the effects of jugular infusion of 2 groups of AA on essential AA uptake and metabolism by mammary glands in a 4 x 4 Latin square design. Treatments were jugular infusion of saline (CON), methionine plus lysine plus histidine (MKH), isoleucine plus leucine (IL), or MKH plus IL (MKH+IL). The MKH increased milk protein yield in high producing dairy cows. The IL infusion increased milk and milk lactose yields. The production response was associated with a change in mammary plasma flow together with changes in AA uptake and metabolism in mammary gland. Mammary uptake of essential AA was 135 % of milk protein output. Efflux of EAA from the mammary to blood was 13-61% of influx, which was high for BCAA but low for Met and Lys. Changes in influx and efflux resulted in net uptake difference of infused essential AA that were responsive to varying supplies resulting in maintenance of homeostasis. The proportion of AA catabolized and used for milk protein was affected by EAA infusion, which demonstrated plasticity of mammary gland in AA metabolism. Overall, results suggested essential AA availability from rumen undegraded protein and microbial protein varied across individual AA and diets and can be affected by rumen fermentation. After absorption, EAA transport into mammary tissue was bi-directional and their metabolism was affected by AA supply and energy. Using a single coefficient to represent all AA digestibility in MCP or feed ingredient and an integrated efficiency of MP-AA converted into milk protein is inaccurate.Doctor of Philosophy
Studies in monogastric animals have showed that balancing AA supply with animal requirements can improve the efficiency of N utilization. In order to build a model for AA balanced diet formulation, the composition of feed ingredients, the profile and digestibility of EAA for the rumen undegradable protein and microbial protein, the partition and efficiency of EAA utilization in mammary glands must be determined accurately. However, current AA degradation, digestibility and metabolism data used in nutritional models are from in vitro and in situ studies, which have not been fully validated against in vivo observations. This research used an in vivo stable isotope-based approach to determine amino acid availability for commonly used feed ingredients in dairy industry. The microbial protein AA and rumen undegradable protein AA availability was determined by adapting this isotope technique and introducing another isotope into rumen to label microbes. In addition, by coupling stable isotope tracers with arterio-venous difference technique and compartmental modelling, essential AA metabolism in mammary glands of dairy cows were qualified. Total essential AA availabilities for corn silage, grass hay, alfalfa hay, dried distillers grain, soyhulls, brewers grain and corn grain were similar to values from meta-analysis of mobile bag results, but the availabilities of individual AA were more variable compared to in vitro and in situ results. The model derived microbial AA availability was consistent with the microbial protein calculated from NDS and Felming's model. However, our model predicted a lower proportion of metabolizable AA from microbial protein under diets including low rumen degradable protein, which might imply the NDS nutritional model overestimates microbial protein under low protein diets. The microbial protein estimated from White's model showed the same trend among treatments compared to isotope dilution model, which may imply it represents the rumen fermentation better. The averaged essential AA digestibility form microbial protein was 82%, which varied across individual AA and treatments. After absorption, mammary uptake of essential AA was 135 % of milk protein output. Cellular efflux represented 13 to 61% of essential AA uptake. The proportion of AA catabolized and used for milk protein was affected by essential AA infusion, which demonstrated the plasticity of mammary glands in AA metabolism. In conclusion, the results from isotope technique quantified the essential AA availability from rumen undegradable protein for various feed ingredients and from microbial protein under different feeding conditions. The essential AA transport and metabolism in mammary glands were regulated by multi factors and essential AA supply.
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Vieillevoye, Stéphanie. "Effects of a combined essential amino acid-carbohydrate supplementation following heavy-load resistance exercise and training". Doctoral thesis, Universite Libre de Bruxelles, 2021. https://dipot.ulb.ac.be/dspace/bitstream/2013/327090/4/These.pdf.
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An increase in myofibrillar protein accretion can occur in the very early post-exercise period and can be potentiated by dietary protein intakes. The positive effect of nutrition on net muscle protein balance is credited to essential amino acids (EAAs), and particularly to the branched-chain amino acid leucine. Thus, leucine plays a key role in feeding-induced muscle protein synthesis by its unique ability to activate signalling pathways modulating translational initiation (Dreyer et al. 2008). Furthermore, strength exercise induces important disturbances in protein turnover, especially in novice athletes, and unaccustomed physical exercise, particularly repeated eccentric muscle contractions, induces muscle soreness and alterations in muscle cellular structure. Still, muscle strength gains induced by resistance training are mainly attributed to neural adaptations in the initial part of training, and subsequently to changes in the force capacity of muscle fibres due to hypertrophy (Duchateau et al. 2006; Sale, 1988). Since acute post-exercise muscle protein accretion does not inform on chronic muscle adaptations, the main purpose of this work is to test the effectiveness of an EAA supplementation on muscle hypertrophy and strength gains in response to resistance training, and on repair-oriented remodelling of disrupted muscle fibres in the early recovery period of an unaccustomed exercise. The first investigations aim at evaluating the effects of an EAA supplementation on muscle mass, architecture, and strength in the early stages of a heavy-load training programme, and at establishing if the enrichment of the supplement with leucine induces greater improvements in these muscle functional adaptations. In a second part, central and peripheral adaptations are examined following training to compare whether EAA supplementation modifies the relative contribution of neural and muscular factors to the increase in muscle torque, and promotes adaptations in muscle mechanical and contractile properties. The purpose of the third investigation is to study the potential effects of an EAA supplementation on the reduction in the efflux of indirect markers of muscle damage and the delayed onset muscle soreness in the week following a heavy-load eccentric training session.In the first and in the second investigation, young males trained for 12 weeks. They were divided into a placebo (PLA) group (n = 14), an EAA group (n = 15) and a leucine (LEU) group (n = 14). At baseline, daily food intakes and nitrogenous balance were assessed with a food questionnaire over 7 days and two 24h urine collections. The effect of training on muscle mass was assessed by anthropometric techniques. Muscle thickness and pennation angle were recorded by ultrasonography of the medial gastrocnemius (MG). Maximal strength during squat and bench press exercises was tested on an isokinetic ergometer. The torque produced by the plantar flexors and the surface electromyogram (EMG) from the soleus (Sol) and MG were recorded during maximal voluntary isometric contractions (MVC). Central activation was tested by the superimposed electrical stimulation method during MVC and by computing the ratio between voluntary average EMG and compound muscle action potential (M wave) induced by electrical stimulation (average EMG/M-wave). Contractile properties of the plantar flexor muscles were investigated by recording the mechanical responses to single and paired maximal stimuli. In the third investigation, young males performed a bench press exercise in eccentric condition. They were subdivided into a PLA group (n=11) and an EAA group (n=12). The effect of the training session was assessed by analysing two indirect markers of muscle damage, namely creatine kinase (CK) and myoglobin (Mb). Plasma concentrations were measured before, immediately after, and on post-workout days 1, 2, 3, 4 and 7. Muscle soreness was evaluated by a visual analogic scale (VAS) at the same time points as the markers of muscle damage.Resistance training resulted in significant increases in muscle mass and strength in all PLA, EAA and LEU groups with no statistical differences between groups. A positive linear regression was found between nitrogen balance and the increase in muscle mass in the PLA group only. When strength was normalised to skeletal muscle mass, negative linear regressions were observed between the normalised initial strength and the increase in muscle strength in both EAA and LEU groups. EAA and LEU ingestion induced changes in MG muscle architecture in response to training. After training, plantar flexor torque recorded during MVC was increased in PLA, EAA and LEU groups. Central activation level was enhanced with no effect of EAA supplementation. Twitch torque evoked by single and paired supramaximal stimuli, maximal rate of torque development to single stimulus and rate of torque relaxation to single and paired stimulus were significantly improved in the LEU group in response to training. The eccentric training session induced a significant increase in muscle soreness in both PLA and EAA groups. Plasma CK release increased significantly at D+3 and D+4 and Mb efflux rose at D+3 in PLA group only. No statistical differences were observed between groups for the two indirect markers of muscle damage. Gaussian distribution was found to be the best fit model for plasma Mb and CK concentration curves. F-test showed that individual curves were statistically distinguishable when comparing the best-fit values of the three parameters (area, SD and mean) between PLA and EAA group data sets (P < 0.01).In summary, the data indicates that EAA supplementation results in similar muscle mass and strength adaptations in response to resistance training with no additional effect by the enrichment of the supplement with LEU. However, the nutritional interventions appear to be more effective in subject having a lower initial nitrogen balance and/or a lower initial strength, potentially by promoting changes in muscle architecture. EAA ingestion does not potentiate neural adaptations, but leucine-enriched EAA supplementation may induce earlier peripheral adaptations, resulting in enhanced torque production and transmission. Finally, EAA supplementation could have minor effects on the overall plasmatic release of indirect markers of muscle damage during the recovery period without any impact on delayed onset muscle soreness.Doctorat en Sciences de la motricité
info:eu-repo/semantics/nonPublished
Libros sobre el tema "Essential amino acid"
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Ballentine, Carol L. The essential guide to amino acids. Rockville, Md: Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, 1986.
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Ballentine, Carol L. The essential guide to amino acids. Rockville, Md: Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, 1986.
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Kubis, Greta. Essential amino acids and food intake of rats. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1992.
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Anthony, Sandra Patricia. The effects of protein, essential and non-essential amino acids on food intake and selection in rats. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1991.
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1947-, Priestley Joan, ed. Essential supplements for women: What every woman should know about vitamins, minerals, enzymes & amino acids. New York, NY: Perigee Books, 1988.
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Markison, Stacy. Behavioral recovery from essential amino acid deficiency. 1998.
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Miller, Ffrench Rebecca. Whole protein vegetarian: Delicious plant-based recipes with essential amino acids for health and well-being. 2016.
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Lee, Gregory. Epitope/Peptide-Based Monoclonal Antibodies for Immunotherapy of Ovarian Cancer. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190248208.003.0007.
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Two monoclonal antibodies, RP215 and GHR106, were selected, respectively, for the research and development of anti-cancer drugs targeting ovarian cancer and other types of human cancer. RP215 was shown to react with a carbohydrate-associated epitope located mainly in the variable regions of immunoglobulin heavy chains expressed on the surface of almost all cancer cells in humans. GHR106 was generated against a synthetic peptide corresponding to N1-29 amino acid residues in the extracellular domains of human GnRH receptor, which is surface-expressed by most cancer cells as well as the anterior pituitary. This monoclonal antibody was shown to serve as a bioequivalent analog to GnRH-derived decapeptides currently used clinically. The molecular mechanisms of action of these two antibody-based anti-cancer drug candidates were well elucidated following numerous biochemical, immunological, and molecular biological studies, mainly by using ovarian cancer as the model. Further preclinical studies with humanized forms of these two antibodies are essential.
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Ffrench, Rebecca. Whole Protein Vegetarian: Delicious Plant-Based Recipes with Essential Amino Acids for Health and Well-Being. Norton & Company, Incorporated, W. W., 2016.
Buscar texto completoCapítulos de libros sobre el tema "Essential amino acid"
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van der Hulst, R. R. W. J., M. F. von Meyenfeldt y P. B. Soeters. "Glutamine: A Gut Essential Amino Acid". En Update in Intensive Care and Emergency Medicine, 318–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-642-80224-9_22.
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Jacobs, M., V. Frankard, M. Vauterin, E. Suharyanto y J. Tadesse. "Manipulating Essential Amino Acid Metabolism in Plants". En Plant Biotechnology and In Vitro Biology in the 21st Century, 303–6. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4661-6_70.
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He, Wenliang, Peng Li y Guoyao Wu. "Amino Acid Nutrition and Metabolism in Chickens". En Advances in Experimental Medicine and Biology, 109–31. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-54462-1_7.
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AbstractBoth poultry meat and eggs provide high-quality animal protein [containing sufficient amounts and proper ratios of amino acids (AAs)] for human consumption and, therefore, play an important role in the growth, development, and health of all individuals. Because there are growing concerns about the suboptimal efficiencies of poultry production and its impact on environmental sustainability, much attention has been paid to the formulation of low-protein diets and precision nutrition through the addition of low-cost crystalline AAs or alternative sources of animal-protein feedstuffs. This necessitates a better understanding of AA nutrition and metabolism in chickens. Although historic nutrition research has focused on nutritionally essential amino acids (EAAs) that are not synthesized or are inadequately synthesized in the body, increasing evidence shows that the traditionally classified nutritionally nonessential amino acids (NEAAs), such as glutamine and glutamate, have physiological and regulatory roles other than protein synthesis in chicken growth and egg production. In addition, like other avian species, chickens do not synthesize adequately glycine or proline (the most abundant AAs in the body but present in plant-source feedstuffs at low content) relative to their nutritional and physiological needs. Therefore, these two AAs must be sufficient in poultry diets. Animal proteins (including ruminant meat & bone meal and hydrolyzed feather meal) are abundant sources of both glycine and proline in chicken nutrition. Clearly, chickens (including broilers and laying hens) have dietary requirements for all proteinogenic AAs to achieve their maximum productivity and maintain optimum health particularly under adverse conditions such as heat stress and disease. This is a paradigm shift in poultry nutrition from the 70-year-old “ideal protein” concept that concerned only about EAAs to the focus of functional AAs that include both EAAs and NEAAs.
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Kimura, Yukitaka, Motohiro Shima, Tomoyuki Notsu, Shuji Adachi y Ryuichi Matsuno. "Trypsin-Catalyzed Synthesis of Oligopeptides Containing Hydrophilic and Essential Amino Acid, L-Lysine". En Developments in Food Engineering, 582–84. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2674-2_187.
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Suzuki, Toyofumi, Yumiko Miyazaki, Aya Ohmuro, Masaki Watanabe, Takayuki Furuishi, Toshiro Fukami y Kazuo Tomono. "Blood–Brain Barrier Transport of an Essential Amino Acid After Cerebral Ischemia Reperfusion Injury". En Brain Edema XV, 297–302. Vienna: Springer Vienna, 2013. http://dx.doi.org/10.1007/978-3-7091-1434-6_58.
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Bessman, Samuel P., Phyllis Acosta, Rita Harper y Molly Towell. "Essential Nature of the “Dispensable” Amino Acids and Their Possible Influence on the Development and Function of the Brain, with a Note on the Question of Whether the Fetus Really Concentrates Amino Acids from the Mother’s Blood". En Amino Acid Availability and Brain Function in Health and Disease, 13–19. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73175-4_2.
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Ng, Siew Teng, Chuii Khim Chong, Yee Wen Choon, Lian En Chai, Safaai Deris, Rosli M. Illias, Mohd Shahir Shamsir y Mohd Saberi Mohamad. "Using Particle Swarm Optimization for Estimating Kinetics Parameters on Essential Amino Acid Production of Arabidopsis Thaliana". En Advances in Biomedical Infrastructure 2013, 51–61. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37137-0_7.
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Rom, Oren, Sharon Kaisari, Dror Aizenbud y A. Z. Reznick. "Essential Amino Acid Leucine and Proteasome Inhibitor MG132 Attenuate Cigarette Smoke Induced Catabolism in C2 Myotubes". En Neurobiology of Respiration, 25–33. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6627-3_4.
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Gooch, Jan W. "Essential Amino Acids". En Encyclopedic Dictionary of Polymers, 891. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_13698.
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Dunford, James C., Louis A. Somma, David Serrano, C. Roxanne Rutledge, John L. Capinera, Guy Smagghe, Eli Shaaya et al. "Essential Amino Acids". En Encyclopedia of Entomology, 1362. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6359-6_3666.
Texto completoActas de conferencias sobre el tema "Essential amino acid"
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KIM, SUNG-IL y KWANG-JOO KIM. "THE SHAPE CONTROL OF ESSENTIAL AMINO ACID USING CRYSTALLIZATION METHOD". En Proceedings of the 4th International Conference. WORLD SCIENTIFIC, 2004. http://dx.doi.org/10.1142/9789812702623_0170.
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ISMAILOV, Ismail Sagidovich, Nina Vladimirovna TREGUBOVA, Rashid Hasanbievich KOCHKAROV, Anna Victorovna MORGUNOVA y Natalija Alecseevna DRIZHD. "THE RELATIONSHEEP OF AMINO ACID METABOLISM WITH PRODUCTIVITY OF GROWING YOUNG SHEEP". En RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.125.
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A number of studies on digestion of the ruminants have shown the process of synthesis of all the essential amino acids in the rumen (Abu Fadel, 2004; Trukhachev, V., Zlidnev, N. 2008). However, according to some researches, microbial protein is deficient in methionine and lysine. This assumption also proves the need for further study of the influence of balanced amino acids to these diets on the growth, development and productive performance of the ruminants. Scientific approbation of the issues related to establishing the requirements of young sheep in lysine and methionine with cystine and development of recommendations for their proper balance in animal rations have been conducted along with a series of physiological, scientific and practical experiments. For this purpose, we used the following research methods: preparative, analytical, measuring and calculating. Zootechnical evaluation of young sheep’s diet with different levels of lysine and methionine with cysteine has been conducted, and influence of these components on growth, development, metabolism, the use of amino acids and wool productivity have been studied. The importance of studying the content of amino acids in plasma is evident because they are the indicators of protein metabolism in the animals’ organism and represent themselves the exchange fund when used in the biochemical transformations in the process of updating the protein of the body tissues and the synthesis of animal products. Increase in young sheep’s diet of lysine and methionine can improve their productivity, reduce the cost of feed energy and improve biochemical indexes of meat, taking into account the optimization of its amino acid composition. Efficiency increase of young sheep during the process of the individual development is linked to conditions of feeding and in particular the usefulness of a protein food, which is primarily determined by sufficient intake of essential amino acids - lysine and methionine with cystine. Thus, the inclusion in the diet of growing young sheep some amount of synthetic amino acids – 6–8 grams of lysine and 3–4 g of methionine per 1 fodder unit, enhances oxidation-reduction processes, increase productivity, i.e. wool yield and other indicators. The content of free amino acids in plasma directly depends on their availability in feed. The use of synthetic amino acids (lysine, methionine and cystine) contributed to the increase of their content in a free state in the blood serum, indicating their increased demand in sheep. With the use of different doses of synthetic amino acids (lysine, methionine, cystine) in the diets of young sheep it has been found that the organization of optimum conditions of feeding, care and management of sheep in winter season help to avoid abrupt changes in the structure of the skin, to ensure the normal development of the histological structure and morphogenetic processes.)
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Gaivoronskaya, Irina y Valenitna Kolpakova. "MATHEMATICAL MODELS FOR THE SYNTHESIS OF PLANT-BASED COMPOSITIONS WITH IMPROVED AMINO ACID COMPOSITION". En GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/12.
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The aim of the work was to optimize the process of obtaining multicomponent protein compositions with high biological value and higher functional properties than the original vegetable protein products. Was realized studies to obtain biocomposites on the base of pea protein-oat protein and pea protein-rice protein. Developed composites were enriched with all limited amino acids. For each of the essential amino acids, the amino acid score was 100% and higher. Protein products used in these compositions are not in major allergen list, which allows to use these compositions in allergen-free products and specialized nutrition. To determine biosynthesis parameters for compositions from pea protein and various protein concentrates with the use of transglutaminase enzyme, was studied effect of concentration and exposition time on the amount of amino nitrogen released during the reaction. Decreasing of amino nitrogen in the medium indicated the occurrence of a protein synthesis reaction with the formation of new covalent bonds. Were determined optimal parameters of reaction: the hydromodule, the exposure time, the concentration of EP of the preparation, were obtained mathematical models. Studies on the functional properties of composites, the physicochemical properties of the proteins that make up their composition, and structural features will make it possible to determine the uses in the manufacture of food products based on their ability to bind fat, water, form foam, gels, and etc.
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Meade, J. B., C. M. Noyes y F. C. Church. "IDENTIFICATION OF LYSINES IN HUMAN THROMBIN ESSENTIAL FOR HEPARIN BINDING AND CLOTTING ACTIVITY". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644662.
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We are studying human thrombin (IIa) in order to determine the significance of particular amino acid residues critical for interaction with various substrates and cofactors.Previously, we demonstrated the importance of lysyl residues of Ila during interaction with heparin as well as fibrinogen (Griffith, M.J., (1979) J. Biol. Chem. 254:3401; Church, F.C., et al., (1985) J. Biol. Chem. 260:4936). Identification of these essential lysyl residues in Ila has been approached by chemical modification using the amino group-specific reagent pyridoxal-5'-phosphate (PLP) in the presence and absence of heparin. Ila phosphopyri-doxylated in the absence of heparin (unprotected) showed approximately 2 mols of PLP incorporated per mol of Ila and had greatly reduced inhibition by antithrombin III (ATIII)-heparin as well as reduced clotting activity. Ila phosphopyridoxylated in the presence of heparin (protected) showed approximately 1 mol of PLP incorporated per mol of Ila and had reduced clotting activity but essentially normal inhibition by ATIII-heparin. Both modified thrombins showed normal inhibition by ATIII and heparin cofactor II in the absence of heparin at 25×C and pH 8.0 with apparent second-order rate constant values ranging from 3-5 × 10-5 and 4-6 × 10-4 M-1 min-1, respectively. In contrast to native Ila, neither protected nor unprotected PLP-Ila derivatives bound to a fibrin monomer-agarose column equilibrated at 25×C with 50 mM Tris-HCl, 50 mM NaCl, pH 7.4. Samples of both modified thrombins were reductively denatured, S-carboxymethylated, and hydrolyzed with trypsin at 37×C. The resultant peptide mixtures were separated using reverse-phase high performance liquid chromatography. Peptides showing a high degree of PLP incorporation were sequenced by automated Edman degradation and the modified lysyl residues were identified in the primary sequence of Ila. In unprotected-IIa, lysyl residues 21, 65, 174 and 252 of the B-chain were modified. In heparin-protected-IIa, only Lys 21 and 65 of the B-chain were modified. These results suggest that Lys 174 and 252 of the B-chain of thrombin are essential for binding to heparin and that Lys 21 and/or 65 are essential for clotting activity.
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Kulikov, Denis, Ruzaliya Ulanova y Valentina Kolpakova. "COMPREHENSIVE BIOTECHNOLOGICAL APPROACH TO PROCESSING OF PEA FLOUR FOR FOOD AND FODDER PURPOSES". En GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/06.
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Investigations were carried out to optimize the growth parameters of the symbiosis of cultures of the yeast Saccharomyces cerevisiae 121 and the fungus Geotrichum candidum 977 on whey waters formed from pea flour as a secondary product in the production of protein concentrates after precipitation of proteins at the isoelectric point. The whey remaining after protein precipitation is bioconverted at optimal parameters of crop growth (pH of the medium, amount of inoculum, temperature) with the formation of microbial plant concentrate (MPC) for feed purposes. Serum cultures assimilated stachyose, glucose, maltose, arabinose, and other pentoses. The mass fraction of protein in the concentrate was 57.90-61.68 % of DS. The composition of MPC obtained from biomass is balanced in essential amino acids with a speed of 107-226 %. The fatty acid composition is represented by 97 % fatty acids and 3 % - esters, aldehydes, ketones with the properties of fragrances, photo stabilizers, odor fixers, preservatives and other compounds. The ratio of the sum of saturated and unsaturated acids is 1:3, the content of cis-isomers is 91.1 %, trans-isomers are 5.1 %, omega-6 fatty acids are 19.73 %. The quality and safety indicators indicated that it is promising for use in the diet of animals.
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Solis-Calero, C., PA Morais, FF Maia Jr, VN Freire y HF Carvalho. "Explaining SARS-CoV-2 3CL Mpro binding to peptidyl Michael acceptor and a ketone-based inhibitors using Molecular fractionation with conjugate caps method". En VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020185.
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The main protease SARS-CoV-2 3CL Mpro (3CL-Mpro) is an attractive target for developing antiviral inhibitors due to its essential role in processing the polyproteins translated from viral coronavirus RNA. In this work, it was obtained non-covalent complexes of this protease with two distinct ligands, a peptidyl Michael acceptor (N3) and a ketone-based compound (V2M). The complexes were modeled from processed crystallographic data (PDB id: 6LU7 and 6XHM respectively) using combined quantum mechanics/molecular mechanics (QM/MM) calculations. The QM region was treated at the PBE-def2-SV(P) level, while the Amber-ff19SB force field was used to describe the MM region. The obtained models were used to perform calculations for describing the protease/ligand binding, based in the framework of the Density Functional Theory (DFT) and within the Molecular Fractionation with Conjugated Caps (MFCC) scheme. Our results have shown values for the total interaction energies of -111.84 and -111.64 kcal mol-1 having as ligands a N3 and V2M, respectively. Most importantly, it was possible to assess the relative individual amino acid energy contribution for the binding of both ligands considering residues around them up to 10 Å of radial distance. Residues Gln189, Met165, Glu166, His164, and Asn142 were identified as main interacting amino acid residues for both complexes, being their negative interaction energy contributions higher than -5.0 kcal mol-1. In the case of 3CL-Mpro/ V2M complex, we should add His41, Ser144, and Cys145 as main contributing residues. Our data also have shown that interactions of type π-amide, π-alkyl and alkyl-alkyl and carbon hydrogen bonds should be also considered in order to explain the binding of 3CL-Mpro with the selected inhibitors. Our results also determined that the carbonyl-L-leucinamide scaffold of both inhibitors is its main determinant of binding with a contribution to the energy of interaction of 54.51 and 50.69 kcal mol-1 for N3 and V2M, respectively.
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Wang, Qin, Jun Wei, Boyuan Wang, Zhen Li, Sheng Wang y Shuguang Cui. "Adaptive Residue-wise Profile Fusion for Low Homologous Protein Secondary Structure Prediction Using External Knowledge". En Thirtieth International Joint Conference on Artificial Intelligence {IJCAI-21}. California: International Joint Conferences on Artificial Intelligence Organization, 2021. http://dx.doi.org/10.24963/ijcai.2021/490.
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Protein secondary structure prediction (PSSP) is essential for protein function analysis. However, for low homologous proteins, the PSSP suffers from insufficient input features. In this paper, we explicitly import external self-supervised knowledge for low homologous PSSP under the guidance of residue-wise (amino acid wise) profile fusion. In practice, we firstly demonstrate the superiority of profile over Position-Specific Scoring Matrix (PSSM) for low homologous PSSP. Based on this observation, we introduce the novel self-supervised BERT features as the pseudo profile, which implicitly involves the residue distribution in all native discovered sequences as the complementary features. Furthermore, a novel residue-wise attention is specially designed to adaptively fuse different features (i.e., original low-quality profile, BERT based pseudo profile), which not only takes full advantage of each feature but also avoids noise disturbance. Besides, the feature consistency loss is proposed to accelerate the model learning from multiple semantic levels. Extensive experiments confirm that our method outperforms state-of-the-arts (i.e., 4.7% for extremely low homologous cases on BC40 dataset).
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Choay, J., M. Petitou, B. Perly, B. Casu, M. Ragazzi y D. Ferro. "MOLECULAR CONFORMATION OF THE PENTASACCHARIDE CORRESPONDING TO THE BINDING SITE OF HEPARIN TO ANTITHROMBIN III". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642828.
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The knowledge of the tridimensional structure of the sequence required in heparin for binding to anti thrombin III (AT) is essential for the understanding of the molecular basis of the anticoagulant and antithrombotic activity of this glycosamino-glycan. This problem was approached by a combined experimental (chemical synthesis and Nuclear Magnetic Resonance, "NMR") and theoretical (force field calculations) study of the pentasaccharide I reproducing the minimal sequence for high affinity binding to AT.NMR data (interproton coupling constants and nuclear-Over-hauser-enhancement) were used to test a number of possible conformation of I proposed on the basis of-molecular energy calculation. In particular, these studies, confirming the results obtained by force field calculations, showed that the sulfated iduronic residue (Is) conformation is an equilibrium between the chair 4C4 and the skew boat2S0, and permitted to discard models with the Is residue in the alternate chair 4C1. It is of interest that the relative population of the 4C4 and 2S0 conformers of IS in sequence I (40:60) is reversed with respect to that found for the same residue in the regular sequences of heparin (60:40), such a reversal being largely associated with electrostatic interactions caused by the unique 3-0-sulfo group ot the preceding amino sugar residue. The most favoured models of I are characterized by a cluster of anionic groups including all the sulfate groups proposed as essential for full expression of the activity (full line square on the formula) but one (dotted line square on the formula), plus the carboxylate group of the glucuronic acid residue.
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Banerjee, Dipti, Debanjali Roy y Priyanka Saha. "The Absorbed Energy of Essential Amino Acids by Geometric Phase". En Frontiers in Optics. Washington, D.C.: OSA, 2018. http://dx.doi.org/10.1364/fio.2018.jw3a.25.
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Valadares Filho, S. C., P. M. Amaral, D. Zanetti, L. D. S. Mariz, S. A. Santos, S. A. Lopes, L. F. Prados et al. "Net essential amino acids requirements for Nellore and crossbred Angus × Nellore cattle". En 6th EAAP International Symposium on Energy and Protein Metabolism and Nutrition. The Netherlands: Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-891-9_151.
Texto completoInformes sobre el tema "Essential amino acid"
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Geppert, Taylor C., Allison Meyer y Patrick J. Gunn. Effects of Increasing Supplementation of Rumen Undegradable Protein on Plasma Essential Amino Acid Concentrations in Beef Cows Consuming Low Quality Forage. Ames (Iowa): Iowa State University, enero de 2015. http://dx.doi.org/10.31274/ans_air-180814-1272.
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