Relevant bibliographies by topics / Cephalosporin C

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Academic literature on the topic 'Cephalosporin C'

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Published: 4 June 2021
Last updated: 8 February 2022

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Journal articles on the topic "Cephalosporin C"

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Hardianto, Dudi, Bima Wedana Isdiyono, and Fransiskus Xaverius Ivan. "BIOKONVERSI SEFALOSPORIN C MENJADI ASAM 7-AMINOSEFALOSPORANAT DENGAN SEFALOSPORIN ASILASE." Jurnal Bioteknologi & Biosains Indonesia (JBBI) 3, no. 2 (December 13, 2016): 89. http://dx.doi.org/10.29122/jbbi.v3i2.139.

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Cephalosporins are the most widely used class of β-lactam antibiotic in the world and clinically active against gram positive and gram negative bacteria. Cephalosporin C (CPC) is naturally produced by fungus Cephalosporiun acremonium. CPC has moderate antibacterial activity with minimum inhibitory concentration values of 25-100 µg/mL and 12-25 µg/mL for gram-positive and for gram-negative bacteria, respectively. CPC can be converted into 7-aminocephalosporonic acid (7-ACA) as intermediate compound for cephalosporin derivatives by two-steps or one-step enzymatic method. Two-step enzymatic method uses D-amino acid oxidase (DAAO) to produce glutaryl-7-amino cephalosporanic acid (GL 7-ACA) for the first step and GL-7-ACA acylase to produce 7-ACA for the second step. One-step enzymatic method uses CPC acylase to convert CPC into 7-ACA directly. Some microorganisms produce CPC acylase, such as Pseudomonas sp., Bacillus megaterium, Aeromonas sp., dan Arthrobacler. A natural CPC acylase has low activity and genetic engineering was used to increase its activity.Keywords: Cephalosporin, cephalosporin acylase, 7-ACA, genetic engineering, mutation ABSTRAKSefalosporin merupakan antibiotik golongan β-laktam yang paling banyak digunakan di dunia dan secara klinis aktif terhadap bakteri gram positif dan gram negatif. Sefalosporin C merupakan sefalosporin alami yang dihasilkan oleh kapang Cephalosporium acremonium. Sefalosporin C mempunyai aktivitas antibakteri moderat dengan nilai konsentrasi hambat minimum 25-100 µg/mL untuk bakteri gram positif dan 12-25 µg/mL untuk bakteri gram negatif. Sefalosporin C dapat diubah menjadi asam 7-aminosefalosporanat (7-ACA) sebagai senyawa antara untuk pembuatan turunan sefalosporin dengan metode enzimatik secara dua atau satu tahap. Produksi 7-ACA secara enzimatik dapat menggunakan metode dua tahap dan satu tahap enzimatik. Metode enzimatik secara dua tahap menggunakan enzim asam D-amino oksidase (DAAO) untuk menghasilkan asam glutaril-7-aminosefalosporinat (GL-7-ACA) pada tahap pertama dan menggunakan asam glutaril-7-aminosefalosporinat asilase untuk menghasilkan 7-ACA pada tahap kedua. Metode enzimatik secara satu tahap menggunakan sefalosporin asilase untuk mengubah CPC menjadi 7-ACA secara langsung. Beberapa mikroorganisme penghasil sefalosporin asilase yaitu Pseudomonas sp., Bacillus megaterium, Aeromonas sp., dan Arthrobacter. Aktivitas CPC asilase alami sangat rendah dan rekayasa genetik digunakan untuk meningkatkan aktivitasnya.Kata kunci : Sefalosporin, sefalosporin asilase, 7-ACA, rekayasa genetik, mutasi
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Xiao, X., S. Wolfe, and A. L. Demain. "Purification and characterization of cephalosporin 7α-hydroxylase from Streptomyces clavuligerus." Biochemical Journal 280, no. 2 (December 1, 1991): 471–74. http://dx.doi.org/10.1042/bj2800471.

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Cephalosporin 7 alpha-hydroxylase, which catalyses the conversion of cephalosporins into their 7 alpha-hydroxy derivatives, was purified nearly 390-fold from Streptomyces clavuligerus through ion-exchange chromatography, (NH4)2SO4 fractionation, gel filtration and dye chromatography, with the use of h.p.l.c. to monitor enzyme activity. The nearly pure enzyme migrates as a single major band, with an Mr of 32,000 in SDS/PAGE. Its optimum pH is in the range 7.3-7.7. Under our conditions the reaction was fastest at temperatures in the range 20-30 degrees C. The Km for cephalosporin C is 0.72 mM, and the Vmax. is 15.4 mumol of cephalosporin C hydroxylated/min per mg. Cephalosporin 7 alpha-hydroxylase did not show any deacetoxycephalosporin C synthase or deacetoxycephalosporin C hydroxylase activity.
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Balakrishnan, Nataraj, Sadhasivam Ganesan, Padma Rajasekaran, Lingeshwaran Rajendran, Sivaprasad Teddu, and Micheal Durairaaj. "Modified Deacetylcephalosporin C Synthase for the Biotransformation of Semisynthetic Cephalosporins." Applied and Environmental Microbiology 82, no. 13 (April 15, 2016): 3711–20. http://dx.doi.org/10.1128/aem.00174-16.

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ABSTRACTDeacetylcephalosporin C synthase (DACS), a 2-oxoglutarate-dependent oxygenase synthesized byStreptomyces clavuligerus, transforms an inert methyl group of deacetoxycephalosporin C (DAOC) into an active hydroxyl group of deacetylcephalosporin C (DAC) during the biosynthesis of cephalosporin. It is a step which is chemically difficult to accomplish, but its development by use of an enzymatic method with DACS can facilitate a cost-effective technology for the manufacture of semisynthetic cephalosporin intermediates such as 7-amino-cephalosporanic acid (7ACA) and hydroxymethyl-7-amino-cephalosporanic acid (HACA) from cephalosporin G. As the native enzyme showed negligible activity toward cephalosporin G, an unnatural and less expensive substrate analogue, directed-evolution strategies such as random, semirational, rational, and computational methods were used for systematic engineering of DACS for improved activity. In comparison to the native enzyme, several variants with improved catalytic efficiency were found. The enzyme was stable for several days and is expressed in soluble form at high levels with significantly higherkcat/Kmvalues. The efficacy and industrial scalability of one of the selected variants, CefFGOS, were demonstrated in a process showing complete bioconversion of 18 g/liter of cephalosporin G into deacetylcephalosporin G (DAG) in about 80 min and showed reproducible results at higher substrate concentrations as well. DAG could be converted completely into HACA in about 30 min by a subsequent reaction, thus facilitating scalability toward commercialization. The experimental findings with several mutants were also used to rationalize the functional conformation deduced from homology modeling, and this led to the disclosure of critical regions involved in the catalysis of DACS.IMPORTANCE7ACA and HACA serve as core intermediates for the manufacture of several semisynthetic cephalosporins. As they are expensive, a cost-effective enzyme technology for the manufacture of these intermediates is required. Deacetylcephalosporin C synthase (DACS) was identified as a candidate enzyme for the development of technology from cephalosporin G in this study. Directed-evolution strategies were employed to enhance the catalytic efficiency of deacetylcephalosporin C synthase. One of the selected mutants of deacetylcephalosporin C synthase could convert high concentrations of cephalosporin G into DAG, which subsequently could be converted into HACA completely. As cephalosporin G is inexpensive and readily available, the technology would lead to a substantial reduction in the cost for these intermediates upon commercialization.
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Botnarciuc, Mihaela, Irina Stan, and Sorina Ispas. "Cephalosporin resistant bacterial strains isolated from respiratory infections." ARS Medica Tomitana 21, no. 1 (February 1, 2015): 7–11. http://dx.doi.org/10.1515/arsm-2015-0012.

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Abstract Objectives: The objective of the study is the evaluation of the actual resistance to second, third, and fourth generation cephalosporins over bacterial strains isolated from respiratory infections. The main causes for cephalosporin resistance of pathogenic and conditioned pathogen bacteria are: widespread usage, and impair immune response. Materials and methods: The analyzed specimens were throat swabs and sputum, from adult patients. The tests were performed using disk diffusion technique. We tested the following cephalosporin: From second generation: cefuroxime axetil; from third generation: cefotaxime, ceftazidime, cefpodoxime; Combinations of cephalosporins and beta-lactamase inhibitors: cefotaxime + clavulanic acid; ceftazidim + clavulanic acid; From fourth generation: cefepime; and association cefepime and clavulanic acid. Results: The following bacterial strains were isolated: Staphylococcus aureus, Streptococcus pneumoniae, Group C β-hemolytic Streptococcus, E. coli, Klebsiella pneumoniae and Proteus sp. The Group A. β-hemolytic Streptococcus isolated strains were not tested. For Staphylococcus aureus, E. coli, K. pneumoniae and Proteus, we found a high frequency resistance tocefuroxim, approximately 47%. Highest resistance to third generation cephalosporin was identified to E.coli and Klebsiella pneumoniae, especially resistant to cefotaxime, cefotaxime + clavulanic acid and ceftazidime. Conclusions: Cefpodoxime can be considered as a first election antibiotic in treating upper and lower respiratory tract infections, due to the lowest level of bacterial strain resistance, approximately 10% of the third generation cephalosporines tested. Also, cefepime may be proper in treating severe respiratory tract infections, with resistant broad-spectrum antibiotics bacterial strains. In our trial, resistance to cefepime was to a minimum low, approximately 4%, represented by the E.coli strains.
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Baldwin, Jack E., Robert M. Adlington, Nicholas P. Crouch, and Christopher J. Schofield. "The enzymatic conversion of exomethylene cephalosporin c into deacetyl cephalosporin c and the role of molecular oxygen in cephalosporin c biosynthesis." Tetrahedron 44, no. 2 (January 1988): 643–50. http://dx.doi.org/10.1016/s0040-4020(01)85852-x.

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Braña, Alfredo F., Saul Wolfe, and Arnold L. Demain. "Ammonium repression of cephalosporin production by Streptomyces clavuligerus." Canadian Journal of Microbiology 31, no. 8 (August 1, 1985): 736–43. http://dx.doi.org/10.1139/m85-138.

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Production of β-lactam antibiotics took place during growth of Streptomyces clavuligerus in chemically defined medium. The specific activities of isopenicillin N synthetase ("cyclase"), isopenicillin N epimerase, and deacetoxycephalosporin C synthetase ("expandase") increased during the exponential phase of growth. Specific cephalosporin productivity during fermentation followed a similar pattern, reaching a maximum near the end of the growth phase and decaying rapidly in the stationary phase. Ammonium chloride depressed cephalosporin production, presumably as a result of repression of cyclase and expandase formation, but not of epimerase. No inhibitory effects on enzyme activity by ammonium were found. Addition of tribasic magnesium phosphate [Mg3(PO4)2∙8H2O] prevented the repression of cyclase and markedly stimulated cephalosporin production. Cephamycin C and, in smaller amounts, O-carbamoyldeacetylcephalosporin C were the only cephalosporins detected. Growth with ammonium resulted in lower titers of both compounds, and did not change the relative proportion of each. The correlation found between cephalosporin productivity and cyclase specific activity in different media suggests that formation of this enzyme may be the rate-limiting step in the pathway.
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Hano, Tadashi, Michiaki Matsumoto, Takaaki Ohtake, and Fumiaki Hori. "Reactive extraction of cephalosporin C." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 25, no. 3 (1992): 293–97. http://dx.doi.org/10.1252/jcej.25.293.

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Usher, John J., MaryAnn Lewis, Doris W. Hughes, and Bruce J. Compton. "Development of the cephalosporin C fermentation taking into account the instability of cephalosporin C." Biotechnology Letters 10, no. 8 (August 1988): 543–48. http://dx.doi.org/10.1007/bf01027126.

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Mustika, Indria Puti, and Ahmad Wibisana. "PERAN MUTASI GEN ACY II TERHADAP PRODUKSI ANTIBIOTIK SEFALOSPORIN." Jurnal Bioteknologi & Biosains Indonesia (JBBI) 4, no. 2 (December 30, 2017): 96. http://dx.doi.org/10.29122/jbbi.v4i2.2272.

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The Roles of AcyII Gene Mutations for Production of Antibiotics Derived From CephalosporinSemisynthetic antibiotics cephalosporins are widely used to treat infectious diseases, especially those caused by gram-negative bacteria. Various types of semisynthetic antibiotics could be synthesized using 7-aminocephalosporanic acid (7-ACA) as the main raw material. 7-ACA is obtained by conversion of cephalosporin C, either chemically or enzymatically. Converting cephalosporin C to 7-ACA enzymatically in one step involves the cephalosporin acylase enzyme. Currently, all of cefalosporin acylase enzymes produced by wild-type microbes have only high activity on glutaryl-7-ACA as the main substrate. Genetic engineering of the encoding gene of cefalosporin acylase is required to obtain recombinant enzyme having high activity on cephalosporin C. In this paper, the engineering attempts made on acyII gene from Pseudomonas SE83 using directed mutagenesis, error prone PCR, and structural modeling are described. Keywords: AcyII gene, cephalosporin, cephalosporin C acylase, enzyme activity, mutation ABSTRAKAntibiotik sefalosporin semisintetik banyak digunakan untuk mengatasi penyakit infeksi, khususnya yang ditimbulkan oleh bakteri gram negatif. Berbagai jenis antibiotik semisintetk dapat disintesis menggunakan senyawa asam 7-aminosefalosporanat (7-ACA) sebagai bahan baku utamanya. Senyawa 7-ACA diperoleh melalui konversi sefalosporin C, baik yang dilakukan secara kimiawi maupun enzimatis. Konversi sefalosporin C menjadi 7-ACA secara enzimatis dalam satu langkah melibatkan enzim sefalosporin asilase. Hingga saat ini, seluruh enzim sefalosporin asilase yang dihasilkan oleh mikroba wild type hanya mempunyai aktifitas yang tinggi terhadap glutaryl-7-ACA. Rekayasa genetik terhadap gen pengkode enzim sefalosporin asilase diperlukan untuk memperoleh enzim rekombinan yang mempunyai aktifitas tinggi terhadap substrat sefalosporin C. Dalam ulasan ini diuraikan upaya-upaya rekayasa yang telah dilakukan terhadap gen acyII dari Pseudomonas SE83 menggunakan teknik mutasi terarah, error prone PCR, dan pemodelan struktur.Kata kunci: Aktivitas enzim, gen acyII, mutasi, sefalosporin, sefalosporin C asilase Received: 14September 2017 Accepted: 19 December 2017 Published: 30 December 2017 Received: 14September 2017 Accepted: 19 December 2017 Published: 30 December 2017
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Atroshenko, Denis L., Mikhail D. Shelomov, Sophia A. Zarubina, Nikita Y. Negru, Igor V. Golubev, Svyatoslav S. Savin, and Vladimir I. Tishkov. "Multipoint TvDAAO Mutants for Cephalosporin C Bioconversion." International Journal of Molecular Sciences 20, no. 18 (September 7, 2019): 4412. http://dx.doi.org/10.3390/ijms20184412.

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d-amino acid oxidase (DAAO, EC 1.4.3.3) is used in many biotechnological processes. The main industrial application of DAAO is biocatalytic production of 7-aminocephalosporanic acid from cephalosporin C with a two enzymes system. DAAO from the yeast Trigonopsis variabilis (TvDAAO) shows the best catalytic parameters with cephalosporin C among all known DAAOs. We prepared and characterized multipoint TvDAAO mutants to improve their activity towards cephalosporin C and increase stability. All TvDAAO mutants showed better properties in comparison with the wild-type enzyme. The best mutant was TvDAAO with amino acid changes E32R/F33D/F54S/C108F/M156L/C298N. Compared to wild-type TvDAAO, the mutant enzyme exhibits a 4 times higher catalytic constant for cephalosporin C oxidation and 8- and 20-fold better stability against hydrogen peroxide inactivation and thermal denaturation, respectively. This makes this mutant promising for use in biotechnology. The paper also presents the comparison of TvDAAO catalytic properties with cephalosporin C reported by others.
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Dissertations / Theses on the topic "Cephalosporin C"

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Weisenberger, Klaus. "Downstream processing of cephalosporin c." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330236.

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Norman, Elizabeth. "Biochemical genetics of Cephalosporin C production." Thesis, University of Nottingham, 1988. http://eprints.nottingham.ac.uk/14317/.

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The biosynthetic pathway which leads, in Cephalosporium acremonium, to the production of the commercially important β-lactam antibiotic Cephalosporin C (CPC) has been the subject of extensive biochemical studies and is now well characterized. In contrast, genetic analysis in this organism was limited until the application of protoplast fusion techniques facilitated parasexual analysis and allowed a genetic map to be established. (Hamlyn 1982; Hamlyn et al 1985). Subsequently, work leading to our understanding of the genetic basis of the CPC biosynthetic pathway in C. acremonium began. (Perez-Martinez 1984; Perez-Martinez and Peberdy in preparation). The studies described here were aimed at extending this understanding to a point at which individual genes implicated in the pathway could be identified and positioned on the linkage map. A programme of mutagenesis resulted in the production of a number of 'blocked' mutant strains of C. acremonium which were phenotypically particular steps of the CPC biosynthetic pathway. The segregation of several of these mutations relative to other genetic markers was examined. Crosses designed to detect complementation between mutations resulting in a 'blocked' phenotype were carried out and involved strains produced in other laboratories in addition to those characterized during this work. Complementation was shown between two mutations which apparently affected the same step in CPL biosynthesis (the conversion of penicillin N into deacetoxycephalosporin C) and evidence for the linkage of one of the mutations (cnp-6) to a mutation resulting in a requirement for inositol was obtained. During the course of the complementation studies, it was noted that the haploid and heterozygous products obtained following C. acremonium protoplast fusion crosses did not always behave in the typical manner described previously. (Hamlyn 1984). The persistent heterogeneity of these fusion products and the possible implications of this are discussed.
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Yang, Su-an. "Fundamental studies and mathematical modelling of an adsorptive purification process for cephalosporin-C." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265180.

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Takimoto, Akio. "Studies of production of deacetyl 7-aminocephalosporanic acid with recombinant cephalosporin-C deacetylase." Kyoto University, 2004. http://hdl.handle.net/2433/145437.

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Kyoto University (京都大学)
0048
新制・論文博士
博士(農学)
乙第11556号
論農博第2543号
新制||農||901(附属図書館)
学位論文||H16||N3979(農学部図書室)
22816
UT51-2004-T200
(主査)教授 江﨑 信芳, 教授 清水 昌, 教授 加藤 暢夫
学位規則第4条第2項該当
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Antonio, Tatiana. "Estudo da composição de meios de cultura para a produção de cefamicina C por Streptomuces clavuligerus /." Araraquara : [s.n.], 2007. http://hdl.handle.net/11449/88044.

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Orientador: Maria Lucia Gonsales da Costa Araujo
Banca: Oswaldo Garcia Junior
Banca: Alberto Colli Baldino Junior
Resumo: Os grupos de antibióticos mais importantes clinicamente são os dos b-lactâmicos, aminoglicosídeos e tetraciclinas. Streptomyces clavuligerus produz vários compostos b- lactâmicos, com destaque para os antibióticos envolvidos na rota biossintética da cefalosporina C (penicilina N, deacetoxicefalosporina C e cefamicina C) e o ácido clavulânico (AC) que, embora não tenha atividade biológica significativa, é um potente inibidor de b-lactamases (penicilinases e cefalosporinases). A cefamicina C (CefC) é uma 7-metoxi-cefalosporina que apresenta maior atividade que a cefalosporina C (CPC), produzida somente por fungos, por ser resistente a b-lactamases. Apesar das rotas biossintéticas de AC e CefC serem completamente independentes em S. clavuligerus, são controladas pelo mesmo elemento multifuncional (ccaR), o que dificulta a indução da produção de um ou outro composto durante o processo fermentativo. No presente trabalho, procurou-se obter maiores concentrações de CefC manipulando-se componentes em meio solúvel de cultivo de S. clavuligerus, selecionados dentre compostos que, segundo a literatura, atuam como agentes reguladores da síntese daquele antibiótico. As fermentações foram realizadas em frascos agitados (28ºC, 260 rpm) para selecionar fontes de C e de N e, então, avaliar o processo no melhor meio-padrão, variando-se concentrações combinadas de L-lisina (10 a 108 mM) e -cetoglutarato (3 a 110 mM) através de metodologia de planejamento experimental. A presença de -cetoglutarato acarretou em aumento indesejável de pH, afetando negativamente o processo e os melhores resultados (entre 300 e 400 mg CPC totais/L após 72 horas de fermentação) foram obtidos no meio adotado como meio-controle, contendo amido e extrato protéico de semente de algodão como principais fontes de C e N, respectivamente, e L-lisina.
Abstract: The most important groups of antibiotics, from a clinical standpoint, are -lactams, aminoglycosides and tetracyclines. Streptomyces clavuligerus produces several -lactam compounds, primarily the antibiotics involved in the biosynthetic route of cephalosporin C (penicillin N, deacetoxycephalosporin C and cephamycin C) and clavulanic acid (CA), which, despite its slight biological activity, is a potent inhibitor of -lactamases (penicillinases and cephalosporinases). Cephamycin C (CMC) is a 7-methoxycephalosporin with higher bioactivity than cephalosporin C (CPC) because it is more resistant to -lactamases. Although the biosynthetic routes of CA and CMC are completely independent in S. clavuligerus, they are controlled by a common multi-functional element (ccaR), which hinders induction of the production of one or the other compound during the fermentation process. In this work, we sought to obtain higher concentrations of CMC by handling compounds in a soluble medium of S. clavuligerus, which were selected from compounds that, according to the literature, act as regulating agents in the synthesis of that antibiotic. Fermentation was carried out in flasks under shaking (28ºC, 260 rpm), in order to select sources of C and N. The process was then evaluated in the best standard medium, by varying combined concentrations of lysine (10 to 108 mM) and -ketoglutarate (3 to 110 mM) using an experimental planning methodology. The presence of -ketoglutarate caused an undesirable increase in pH, negatively affecting the process. The best results (between 300 and 400 mg/L of total CPC after 72 h of fermentation) were obtained in the medium used as the control, which contained starch and cottonseed protein extract as main sources, respectively, of C and N, and L-lysine.
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Antonio, Tatiana [UNESP]. "Estudo da composição de meios de cultura para a produção de cefamicina C por Streptomuces clavuligerus." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/88044.

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Os grupos de antibióticos mais importantes clinicamente são os dos b-lactâmicos, aminoglicosídeos e tetraciclinas. Streptomyces clavuligerus produz vários compostos b- lactâmicos, com destaque para os antibióticos envolvidos na rota biossintética da cefalosporina C (penicilina N, deacetoxicefalosporina C e cefamicina C) e o ácido clavulânico (AC) que, embora não tenha atividade biológica significativa, é um potente inibidor de b-lactamases (penicilinases e cefalosporinases). A cefamicina C (CefC) é uma 7-metoxi-cefalosporina que apresenta maior atividade que a cefalosporina C (CPC), produzida somente por fungos, por ser resistente a b-lactamases. Apesar das rotas biossintéticas de AC e CefC serem completamente independentes em S. clavuligerus, são controladas pelo mesmo elemento multifuncional (ccaR), o que dificulta a indução da produção de um ou outro composto durante o processo fermentativo. No presente trabalho, procurou-se obter maiores concentrações de CefC manipulando-se componentes em meio solúvel de cultivo de S. clavuligerus, selecionados dentre compostos que, segundo a literatura, atuam como agentes reguladores da síntese daquele antibiótico. As fermentações foram realizadas em frascos agitados (28ºC, 260 rpm) para selecionar fontes de C e de N e, então, avaliar o processo no melhor meio-padrão, variando-se concentrações combinadas de L-lisina (10 a 108 mM) e -cetoglutarato (3 a 110 mM) através de metodologia de planejamento experimental. A presença de -cetoglutarato acarretou em aumento indesejável de pH, afetando negativamente o processo e os melhores resultados (entre 300 e 400 mg CPC totais/L após 72 horas de fermentação) foram obtidos no meio adotado como meio-controle, contendo amido e extrato protéico de semente de algodão como principais fontes de C e N, respectivamente, e L-lisina.
The most important groups of antibiotics, from a clinical standpoint, are -lactams, aminoglycosides and tetracyclines. Streptomyces clavuligerus produces several -lactam compounds, primarily the antibiotics involved in the biosynthetic route of cephalosporin C (penicillin N, deacetoxycephalosporin C and cephamycin C) and clavulanic acid (CA), which, despite its slight biological activity, is a potent inhibitor of -lactamases (penicillinases and cephalosporinases). Cephamycin C (CMC) is a 7-methoxycephalosporin with higher bioactivity than cephalosporin C (CPC) because it is more resistant to -lactamases. Although the biosynthetic routes of CA and CMC are completely independent in S. clavuligerus, they are controlled by a common multi-functional element (ccaR), which hinders induction of the production of one or the other compound during the fermentation process. In this work, we sought to obtain higher concentrations of CMC by handling compounds in a soluble medium of S. clavuligerus, which were selected from compounds that, according to the literature, act as regulating agents in the synthesis of that antibiotic. Fermentation was carried out in flasks under shaking (28ºC, 260 rpm), in order to select sources of C and N. The process was then evaluated in the best standard medium, by varying combined concentrations of lysine (10 to 108 mM) and -ketoglutarate (3 to 110 mM) using an experimental planning methodology. The presence of -ketoglutarate caused an undesirable increase in pH, negatively affecting the process. The best results (between 300 and 400 mg/L of total CPC after 72 h of fermentation) were obtained in the medium used as the control, which contained starch and cottonseed protein extract as main sources, respectively, of C and N, and L-lysine.
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Lejon, Sara. "Evasion and Attack: Structural Studies of a Bacterial Albumin-binding Protein and of a Cephalosporin Biosynthetic Enzyme." Doctoral thesis, Uppsala : University Library Universitetsbiblioteket, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8399.

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Seidel, Guido. "Kultivierungen mit einem Hochleistungsstamm von Acremonium chrysogenum in komplexen und synthetischen Medien Strategien zur Produktivitätssteigerung unter Berücksichtigung der Enzymaktivitäten der Cephalosporin-C-Biosynthese /." [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=962098469.

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9

Pereira, Inês Antunes Cardoso. "Studies on deacetoxy/deacetylcephalosporin C synthase." Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:d00c6130-a9ec-44f8-a1f5-0465dbaeb4f9.

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This thesis describes an investigation of the mechanism of the bifunctional, a-ketoglutarate dependent dioxygenase, deacetoxy/deacetylcephalosporin C synthase (DAOC/DACS), which catalyses the ring-expansion of penicillin N to deacetoxycephalosporin C (DAOC) and the hydroxylation of this to deacetylcephalosporin C (DAC). The conversion of the unnatural substrate 3-exomethylene cephalosporin C by DAOC/DACS has been investigated in detail. A new metabolite was isolated from incubations of the deuterated [4-2H]-3-exomethylene cephalosporin C, and was identified as the 3β-spiroepoxide cepham, (2Ṟ,3Ṟ,6Ṟ,7Ṟ)-l-aza-[2-2H]-3-spiroepoxy-7-[(5Ṟ)-5-amino- 5-carboxypentanamido]-8-oxo-5-thiabicyclo[4.2.0]octane-2-carboxylic acid. The results obtained indicate that this metabolite is a shunt product whose formation is enhanced by the operation of a deuterium kinetic isotope effect on an enzyme-bound intermediate. It has also been found that this 3β-spiroepoxide cepham is further converted by DAOC/DACS to 3-formyl cephalosporoate products. The mechanism of oxygenation of DAOC/DACS was investigated through 18O-labelling studies. Incubations of [2-13C,3-2H]penicillin N and [4-2H]-3-exomethylene cephalosporin C with DAOC/DACS were carried out under 18O2 or in H218O. Incorporation of 18O-label into the products [3-13C]DAC, [3-13C,4-²H]-3β-hydroxycepham and 3β-spiroepoxide cepham was observed from both sources. The results suggest that intermediates capable of oxygen-exchange are formed during the enzymatic reactions. Two substrate analogues, the 5-epipenicillin N and the 2β-difluoromethyl penicillin N, have been synthesised in order to probe the substrate specificity of DAOC/DACS with respect to the ring-expansion activity. The 5-epipenicillin N was not accepted as a substrate by DAOC/DACS, and the observations made indicate that it was unstable under the incubation conditions. No product was either observed from incubations of the 2β-difluoromethyl penicillin N with DAOC/DACS, although bioassay tests suggested a cephem product had been formed in very small amounts. Finally, the results of a substrate specificity comparison between the soluble recombinant enzymes deacetoxy/deacetylcephalosporin C synthase (DAOC/DACS) from Cephalosporium acremonium and deacetoxycephalosporin C synthase (DAOCS) from Streptomyces clavuligerus are described.
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Andrietta, Maria da Graça Stupiello 1963. "Estudo de meio de cultivo industrial para produção de cefalosporina C por C Cephalosporium acremonium." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256135.

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Orientador: Gil Eduardo Serra
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho teve como objetivo estudar um meio de cultivo industrial para produção de cefalosporina C, utilizando a linhagem C-1 O de Cephalosporium acremonium (A TCC 11550) em experimentos conduzidos em frascos agitados. Foram testadas diferentes fontes de proteína padronizadas, de uso indicado para fermentações industriais, fornecidas pela QUEST INTERNACIONAL - Divisão SHEFFIELD, constituídas à base de soja (Hy-Soy), lacto albumina (Edamin'S), caseína (N-Z Amine A e N-Z Amine As), milho (Hydrolyse Com Gluten ) e algodão (Hydrolyse Cottonseed). As fontes protéicas foram adicionadas a um meio basal, em quantidade equivalente a 4g/1 de nitrogênio total. O meio de cultivo que apresentou uma maior produção de cefalosporina C ( 0,63 gll) foi formulado à base de soja, sendo o meio à base de caseína (N-Z Amine A) o que apresentou uma menor produção do antibiótico. A partir disto foi feito um estudo de cinética da produção de cefalosporina C com esses dois meios de cultivo. Os resultados confirmaram a soja como melhor substrato para produção do antibiótico e mostraram também, ser esta a matéria prima mais produtiva, uma vez que com 144 horas de fermentação houve a produção de 0,93 gll de cefalosporina C. A caseína precisou de 192 horas de fermentação para produzir apenas 0,64 gll do antibiótico. Para os dois substratos testados foi verificada ainda a degradação do antibiótico após o pico de máxima produção. Em uma segunda etapa do trabalho foi avaliada a associação de fontes protéicas na formulação do meio de cultivo. Além de Hy-Soy e Edamin'S, que foram as que apresentaram os melhores resultados na primeira fase, foi introduzido um extrato protéico padronizado, à base de soja (Samprosoy), que é produzido no Brasil pela SANTISTA ALIMENTOS divisão SAMBRA. Neste experimento foram formulados sete diferentes meios de cultivo contendo 4 g/l de N total. Os resultados mostraram um sinergismo na associação de Samprosoy, Hy-Soy e Edamin'S, com uma maior produção do antibiótico (1,43 g/l em 144 horas). Esta composição foi utilizada como ponto central (36 g/l de saca rose, 27 gI1 de glicose e 4 g/l de N total) na primeira fase da otimização do meio de cultivo utilizando planejamento fatorial completo de dois níveis e três variáveis. As variáveis estudadas foram a concentração de sacarose, glicose e nitrogênio, e a variável resposta foi a concentração de cefalosporina C no caldo fermentado. Os resultados obtidos mostraram que maiores concentrações de glicose e nitrogênio levam a um aumento na produção do antibiótico, sendo a variação da concentração de sacarose não significativa na produção da cefalosporina C. Em uma segunda fase da otimização do meio de cultivo o ponto central foi deslocado de modo que esse meio apresentasse maiores concentrações de glicose e nitrogênio (37 g/l de glicose e 6 g/l de N total) e menor quantidade de sacarose (26 g/l). Confirmou-se que altas concentrações de glicose (acima de 45 g/l) e nitrogênio (acima de 6 g/l) direcionam a um aumento na produção, e que a concentração de sacarose não influencia no aumento da produção do antibiótico. Em uma última etapa foi conduzida uma fermentação simultânea em fermentador e em frascos agitados para o estudo do efeito da aeração na produção de cefalosporina C. Parte do meio preparado e inoculado no fermentador foi transferido para frascos Erlenmayer. Os resultados mostram que no fermentador a quantidade de cefalosporina C produzida foi 2,82 vezes maior que as obtidas em frascos agitados. A diferença certamente está associada ao nível constante da concentração de oxigênio no meio de fermentação, possível de se controlar no fermentador, mas não em frascos agitados.
Abstract: The purpose of this work was to study an industrial growing medium for cephalosporin C production in a shaker, using the C-1 O strain of Cephalosporuium acremonium (A TCC 11550). Different sources of standard protein have been tested, all of which recommended for industrial fermentation, and provided by QUEST INTERNACIONAL¬SHEFFIELD Division, soy-based (Hy Soy), Lactoalbumin (Edamin'S), casein (N-Z Amine and N_Z Anime A), com (Hidrolyse Com Gluten) and cotton (Hydrolyse Cottonseed). The protein sources were added to a basic medium amounting to 4 g/l of the total nitrogen. The growing medium that reached the highest cephalosporin C production (0.63 g/l) was soy-based, and the medium that had the lowest amount of the antibiotic was the casein-based (N-Z Amine A). These two growing mediums were then used for a kinetic study of cephalosporin C production. The results have confirmed soybean as the best substratum for the antibiotic production as well as the most productive raw material, since there was a 0.93 g/l cephalosporin C production within 144 hours of fermentation. The casein took 192 hours of fermentation to produce only 0.64 g/l of the antibiotic. It has been observed for both substrata that there was a degradation of the antibiotic after the maximum production peak was reached. In the second stage of the trial, the association of protein sources in the growing medium formulation was evaluated. In the addition to Hy-Soy and Edamin'S, proteins that presented the best results in the first stage, a standard soy-based proteinic extract (Samprosoy) produced in Brazil by SANTISTA ALIMENTOS - SAMBRA division was introduced. Seven different growing mediums containing 4 g/l of total N were formulated. The results have showed a synergism in the association among Samprosoy, Hy-Soyand Edamin'S, with a higher antibiotic production (1,43 g/l within 144 hours). This composition was used as a central point (36 g/l sucrose, 27 g/l glucose and 4 g/l of total N) at the first optimization stage of growing medium a complete two-Level and three-variable factorial design. The variable studied was the sucrose, glucose and nitrogen concentration, and the response variable was the cephalosporin C concentration in the fermented broth. The results have shown that higher glucose and nitrogen concentration have led to an increase in the antibiotic production, even though the variation in sucrose concentration was insignificant for cephalosporin C production. In the second stage of growing medium optimization the central point was dislocated in order to present higher glucose and nitrogen concentrations (37 g/l of glucose and 6 g/l of N total) and lower sucrose concentration (26 g/l). It has been confirmed that high glucose (over 45 g/l) and nitrogen (over 6 g/l) concentration result in an increase in the production, and that sucrose concentration has no effect in the increase of antibiotic production. In the last stage, a simultaneous fermentation in a fermenter and in a shaker was performed for the purpose of studying the aeration effect in cephalosporin C production. Part of the medium prepared and inoculated in the fermenter was transferred to Erlenmeyer flasks. The results have shown that in the fermenter, the amount of cephalosporin C produced was 2.82 times higher than in the shaker. The difference is surely associated with the constant oxygen concentration level in the fermentation medium, which was possible to the controlled in the fermenter but not in the shaker.
Doutorado
Doutor em Tecnologia de Alimentos
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Books on the topic "Cephalosporin C"

1

Glukoseregulation der Cephalosporin C-biosynthese im Hyphenpilz Acremonium chrysogenum. Berlin: J. Cramer, 1999.

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Radzio, Renate. Heterologe Genexpression in dem Cephalosporin C produzierenden Hyphenpilz Acremonium chrysogenum. Berlin: J. Cramer, 1997.

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Nosek, Jörg. Regulation spezifischer Gene in der Cephalosporin C Biosynthese von Acremonium chrysogenum. Berlin: J. Cramer, 1997.

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Der Transkriptionsfaktor CPCR1, ein Regulator der Cephalosporin C-Biosynthesegene in Acremonoim chrysogenum. Berlin: J. Cramer, 1999.

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Heterologe Gene Expression in Dem Cephalosporin C Produzierenden Hyphenpilz Acremonium Chrysogenum (Bibliotheca Mycologica). Gebruder Borntraeger Verlagsbuchhandlung, 1997.

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Regulation Spezifischer Gene in Der Cephalosporin C Biosynthese Von Acremonium Chrysogenum (Bibliotheca Mycologica,). Gebruder Borntraeger Verlagsbuchhandlung, 1997.

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Book chapters on the topic "Cephalosporin C"

1

Schomburg, Dietmar, and Dörte Stephan. "Cephalosporin-C transaminase." In Enzyme Handbook 13, 539–41. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-59176-1_109.

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Schomburg, Dietmar, and Margit Salzmann. "Cephalosporin-C deacetylase." In Enzyme Handbook 3, 175–78. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76463-9_37.

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WILDFEUER, M. E. "Approaches to Cephalosporin C Purification from Fermentation Broth." In ACS Symposium Series, 155–74. Washington, D.C.: American Chemical Society, 1985. http://dx.doi.org/10.1021/bk-1985-0271.ch010.

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Tollnick, C., G. Seidel, M. Beyer, and K. Schügerl. "Investigations of the Production of Cephalosporin C by Acremonium chrysogenum." In New Trends and Developments in Biochemical Engineering, 1–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/b12439.

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Rowatt, Brian, and David C. Sherrington. "Synthesis and Characterisation of Resin Sorbents For Cephalosporin C Recovery." In Ion Exchange Advances, 198–205. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2864-3_26.

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Cruz, A. J. G., M. L. G. C. Araujo, R. C. Giordano, and C. O. Hokka. "Phenomenological and Neural-Network Modeling of Cephalosporin C Production Bioprocess." In Biotechnology for Fuels and Chemicals, 579–92. Totowa, NJ: Humana Press, 1998. http://dx.doi.org/10.1007/978-1-4612-1814-2_53.

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Casillas, J. L., J. L. Garrido, J. Aracil, M. Martinez, F. Addo-Yobo, and C. N. Kenney. "Batch Stirred Tank Adsorption of Impurity of Cephalosporin C, Desacetylcephalosporin C, Using Modified Amberlite XAD-2 Resin." In Separations for Biotechnology 2, 285–94. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0783-6_31.

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Almeida, Renata M. R. G., Antonio J. G. Cruz, Maria Lucia G. C. Araujo, Roberto C. Giordano, and Carlos O. Hokka. "Modeling and Simulation of Cephalosporin C Production in a Fed-Batch Tower-Type Bioreactor." In Twenty-Second Symposium on Biotechnology for Fuels and Chemicals, 537–49. Totowa, NJ: Humana Press, 2001. http://dx.doi.org/10.1007/978-1-4612-0217-2_46.

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Ejchart, A., A. Zimniak, I. Oszczapowicz, and H. Szatylowicz. "Relaxation of 13-C Nuclei in Structural Study on Isomers of Cephalosporin Cefuroxime Axetil." In Spectroscopy of Biological Molecules: Modern Trends, 633. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5622-6_288.

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Seidel, G., C. Tollnick, M. Beyer, and K. Schügerl. "On-line and Off-line Monitoring of the Production of Cephalosporin C by Acremonium chrysogenum." In Bioanalysis and Biosensors for Bioprocess Monitoring, 115–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/3-540-48773-5_4.

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Conference papers on the topic "Cephalosporin C"

1

Shearer, M., K. Andrassy, H. Bechtold, P. McCarthy, J. Koderisch, and H. Koderisch. "CEPHALOSPORIN-INDUCED HYPOPROTHROMBINAEMIA: RELATION TO CEPHALOSPORIN SIDE CHAIN, VITAMIN K METABOLISM AND VITAMIN K STATUS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643076.

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An increased incidence of bleeding episodes due to hypopro-thrombinaemia has been associated with several cephalosporins especially those which contain an N-methyl-thio-tetrazole (NMTT) side chain. To study the etiology of cephalosporin-induced hypo-prothrombinaemia in the clinical situation we have investigated the ability of different cephalosporins to alter the metabolism of vitamin K and the relationship between hypoprothrombinaemia and vitamin K status as assessed from plasma levels of vitamin K. Cephalosporins containing an NMTT side chain (latamoxef, cefmenoxime, cefoperazone, cefotetan, cefamandole) or related structure (cefozolin) all caused the transient plasma appearance of vitamink1 2,3-epoxide in response to a 10 mg intravenous dose of vitamin ; those without NMTT (cefotaxime and cefoxitin) did not. The plasma accumulation of vitamin k1 2,3-epoxide was qualitatively similar to, but quantitatively less than, that produced by the oral anticoagulant phenprccoumon. In 36 patients eating normally, the median endogenous plasma vitamin k1 (370 pg/ml) was not significantly different from that in healthy, fasting subjects (372 pg/ml) and clotting tests remained consistently normal for all antibiotics tested. In 22 patients on total parenteral nutrition the median plasma vitamin k1. (223 pg/ml) was significantly lower than normal (p < 0.01) with 61patients having levels below the normal range (< 150 pg/ml) but normal clotting before starting antibiotic therapy. All 7 parenterally-fed patients treated with latamoxef developed hypoprothrombinaemia (as shown by prothrombin time, PIVKA-II and protein C measurements) within 4 days whereas 12 patients treated with cefotaxime or cefoxitin did not. Latamoxef-associated hypoprothrombinaemia was readily reversible by 1 mg of vitamin k1 given intravenously but hypoprothrombinaemia and sub-normal plasma vitamin k1 could recur within 2-3 days. The data suggest that NMTT-cephalosporins are inhibitors of hepatic vitamin K epoxide reductase and that a lowered vitamin K status predisposes to hypoprothrombinaemia.
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