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Qin, Boyang, Chenyi Fei, Bruce Wang, Howard A. Stone, Ned S. Wingreen, and Bonnie L. Bassler. "Hierarchical transitions and fractal wrinkling drive bacterial pellicle morphogenesis." Proceedings of the National Academy of Sciences 118, no. 20 (May 10, 2021): e2023504118. http://dx.doi.org/10.1073/pnas.2023504118.
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Bacterial cells can self-organize into structured communities at fluid–fluid interfaces. These soft, living materials composed of cells and extracellular matrix are called pellicles. Cells residing in pellicles garner group-level survival advantages such as increased antibiotic resistance. The dynamics of pellicle formation and, more generally, how complex morphologies arise from active biomaterials confined at interfaces are not well understood. Here, using Vibrio cholerae as our model organism, a custom-built adaptive stereo microscope, fluorescence imaging, mechanical theory, and simulations, we report a fractal wrinkling morphogenesis program that differs radically from the well-known coalescence of wrinkles into folds that occurs in passive thin films at fluid–fluid interfaces. Four stages occur: growth of founding colonies, onset of primary wrinkles, development of secondary curved ridge instabilities, and finally the emergence of a cascade of finer structures with fractal-like scaling in wavelength. The time evolution of pellicle formation depends on the initial heterogeneity of the film microstructure. Changing the starting bacterial seeding density produces three variations in the sequence of morphogenic stages, which we term the bypass, crystalline, and incomplete modes. Despite these global architectural transitions, individual microcolonies remain spatially segregated, and thus, the community maintains spatial and genetic heterogeneity. Our results suggest that the memory of the original microstructure is critical in setting the morphogenic dynamics of a pellicle as an active biomaterial.
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Qureshi, Osama, Hira Sohail, Andrew Latos, and Janice L. Strap. "The effect of phytohormones on the growth, cellulose production and pellicle properties of Gluconacetobacter xylinus ATCC 53582." Acetic Acid Bacteria 2, no. 1s (February 26, 2013): 7. http://dx.doi.org/10.4081/aab.2013.s1.e7.
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<em>Gluconacetobacter xylinus</em> is a plant-associated bacterium best studied for its cellulose production. Bacterial cellulose is important in facilitating plant-microbe interactions but little is known about the effect that exogenous phytohormones have on bacterial cellulose synthesis or the growth of <em>G. xylinus</em>. We characterized the growth, development and effect on pellicle characteristics caused by exogenous indole-3- acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin (Z) over a range of concentrations (1 nM to 100 μM). These phytohormones are plant growth regulators known to be involved plant development including fruit ripening and stress tolerance. Each of these hormones stimulated <em>G. xylinus</em> growth and influenced its pellicle characteristics. Exogenous IAA had the greatest effect on <em>G. xylinus</em> pellicles. Growth in IAA produced thin pellicles with very little cellulose. In general, pellicle wet weight was inversely proportional to the bacterial cellulose yield when cultures were grown in the presence of ABA, suggesting ABA influenced pellicle density and hydration. The crystallinity index, CI (IR) of cellulose produced in the presence of each phytohormone over a variety of concentrations was determined by Fourier transform infrared spectroscopy. The observed effect on cellulose crystallinity was concentration and hormone dependent. GA caused the greatest alterations in crystallinity with the highest CI (IR)=0.94 at 1 μM and the lowest CI (IR)=0.47 at 500 nM. Endogenous production of hormones by <em>G. xylinus</em> was investigated by high performance liquid chromatography of extracts prepared from both cell pellets and culture supernatants. We found <em>G. xylinus</em> synthesized GA, ABA and Z but did not produce IAA.
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Skiba, Ekaterina A., Nadezhda A. Shavyrkina, Vera V. Budaeva, Anastasia E. Sitnikova, Anna A. Korchagina, Nikolay V. Bychin, Evgenia K. Gladysheva, et al. "Biosynthesis of Bacterial Cellulose by Extended Cultivation with Multiple Removal of BC Pellicles." Polymers 13, no. 13 (June 28, 2021): 2118. http://dx.doi.org/10.3390/polym13132118.
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Extended cultivation with multiple removal of BC pellicles is proposed herein as a new biosynthetic process for bacterial cellulose (BC). This method enhances the BC surface area by 5–11 times per unit volume of the growth medium, improving the economic efficiency of biosynthesis. The resultant BC gel-films were thin, transparent, and congruent. The degree of polymerization (DP) and elastic modulus (EM) depended on the number of BC pellicle removals, vessel shape, and volume. The quality of BC from removals II–III to VII was better than from removal I. The process scale-up of 1:40 by volume increased DP by 1.5 times and EM by 5 times. A fact was established that the symbiotic Medusomyces gisevii Sa-12 was adaptable to exhausted growth medium: the medium was able to biosynthesize BC for 60 days, while glucose ran low at 24 days. On extended cultivation, DP and EM were found to decline by 39–64% and 57–65%, respectively. The BC gel-films obtained upon removals I–VI were successfully trialed in experimental tension-free hernioplasty.
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Lee, Kwangjoo, Steffen Jockusch, Nicholas J. Turro, Roger H. French, Robert C. Wheland, M. F. Lemon, Andre M. Braun, et al. "157 nm Pellicles (Thin Films) for Photolithography: Mechanistic Investigation of the VUV and UV-C Photolysis of Fluorocarbons." Journal of the American Chemical Society 127, no. 23 (June 2005): 8320–27. http://dx.doi.org/10.1021/ja0440654.
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Wang, Yu. "The investigation of producing bacterial cellulose fibres through hand-spun." E3S Web of Conferences 131 (2019): 01052. http://dx.doi.org/10.1051/e3sconf/201913101052.
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Nanocellulose fibres can be hand-spun from different intermediate states, such as nanocellulose paper and filter cake, which are made from the BC suspension as well as wet pellicle (WP) and dry pellicle (DP) from BC pellicles. In this study, it can be concluded that increasing the hanging weight can increase the Young’s modulus and the tensile strength of fibres. Nanofibres produced from BC pellicles as raw material have better performance than those made from BC suspension. The best properties obtained from the fibres produced from wet pellicles and suspended to a 100g hanging weight upon drying are Young’s modulus (33.8 GPa), tensile strength (610 MPa) and elongation at break (3.6%).
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Kersken, H., J. Vilmart-Seuwen, M. Momayezi, and H. Plattner. "Filamentous actin in Paramecium cells: mapping by phalloidin affinity labeling in vivo and in vitro." Journal of Histochemistry & Cytochemistry 34, no. 4 (April 1986): 443–54. http://dx.doi.org/10.1177/34.4.2419395.
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In living Paramecium cells, microinjected rhodaminyl (R)-phalloidin rapidly labels a thin cortical layer. This can be more clearly resolved with microinjected and fixed cells (allowing for better resolution) as well as with isolated pellicles (surface membrane complexes with trichocysts, microfilaments, and mitochondria attached). Labeling of a longitudinal and perpendicular pattern, reflecting the relief of the cell surface, and labeling of ciliary basal bodies then becomes clearly visible. Other structures labeled by R-phalloidin are the surfaces of food vacuoles of different sizes and, although inconsistently, the borders of the buccal cavity. Small acidic compartments (as identified by acridine orange fluorescence vital staining), probably representing acidosomes and small lysosomes, were not labeled. F-actin on food vacuole surfaces may somehow be involved in intracellular transport or fusion processes. No labeling was observed in association with the osmoregulatory system (contractile vacuoles and their ampullae and radial canals). The specificity of in vivo labeling obtained was supported by the abolition of R-phalloidin labeling when isolated pellicles were pretreated with unlabeled phalloidin or with DNAse I. It was also possible to discriminate among different layers of R-phalloidin binding in the cortex by detaching different layers of the surface complex from each other. Since localization of F-actin in ciliates has raised a considerable amount of dispute in the past, we also repeated all these experiments with RITC-labeled HMM, but we obtained essentially the same labeling pattern as with R-phalloidin. Ciliary basal bodies therefore clearly contain some F-actin. Our data shed some light on aspects of surface structuring and motility in these cells.
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Ahn, S. J., H. S. Kho, S. W. Lee, and D. S. Nahm. "Roles of Salivary Proteins in the Adherence of Oral Streptococci to Various Orthodontic Brackets." Journal of Dental Research 81, no. 6 (June 2002): 411–15. http://dx.doi.org/10.1177/154405910208100611.
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Knowledge of salivary pellicles on orthodontic brackets provides a better understanding of microbial adherence. The aim of this study was to analyze the effects of bracket pellicles on the adherence of Streptococcus gordonii and Streptococcus mutans. Bracket pellicles were formed by the incubation of 4 kinds of orthodontic brackets with unstimulated whole saliva for 2 hrs, and analyzed by electrophoresis, immunodetection, and amino acid analysis. Binding assays were then performed by the incubation of tritium-labeled streptococci with the pellicle-transfer blots and orthodontic brackets. The results showed that low-molecular-weight mucin, α-amylase, secretory IgA, acidic proline-rich proteins, and cystatins adhered to all kinds of brackets, though the amino acid composition of pellicles differed between bracket types. Some of these proteins increased the binding of S. gordonii to saliva-coated brackets. However, salivary pellicles decreased the binding of S. mutans. Collectively, salivary pellicles were found to play a significant role in the initial adhesion of oral streptococci to orthodontic brackets.
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Dickinson, Michelle E., and Adrian B. Mann. "Nanomechanics and morphology of salivary pellicle." Journal of Materials Research 21, no. 8 (August 1, 2006): 1996–2002. http://dx.doi.org/10.1557/jmr.2006.0248.
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Acquired salivary pellicle is a thin protein-rich film formed by the adsorption of saliva onto teeth. It plays important roles in lubrication during mastication and protecting the teeth from chemical attack. Pellicle can become colonized by bacteria to form dental plaque which can lead to dental caries if the bacteria are acidogenic. Abrasive polishing with a dentrifice is used periodically to remove the pellicle from teeth. Pellicle can interact with dietary polyphenolic compounds (tannins) to create extrinsic stains on the tooth surface. The staining can modify the pellicle's mechanical properties and change its morphology resulting in a “squeaky” feeling when the tongue is rubbed over the teeth. Atomic force microscopy imaging and nanoscale mechanical measurements show that unstained pellicle has a dense undulating morphology and is a surprisingly stiff, viscoelastic solid. In contrast, tannin-stained pellicle has fewer but larger surface undulations and exhibits substantial viscous creep.
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Madsen, Jonas S., Yu-Cheng Lin, Georgia R. Squyres, Alexa Price-Whelan, Ana de Santiago Torio, Angela Song, William C. Cornell, Søren J. Sørensen, Joao B. Xavier, and Lars E. P. Dietrich. "Facultative Control of Matrix Production Optimizes Competitive Fitness in Pseudomonas aeruginosa PA14 Biofilm Models." Applied and Environmental Microbiology 81, no. 24 (October 2, 2015): 8414–26. http://dx.doi.org/10.1128/aem.02628-15.
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ABSTRACTAs biofilms grow, resident cells inevitably face the challenge of resource limitation. In the opportunistic pathogenPseudomonas aeruginosaPA14, electron acceptor availability affects matrix production and, as a result, biofilm morphogenesis. The secreted matrix polysaccharide Pel is required for pellicle formation and for colony wrinkling, two activities that promote access to O2. We examined the exploitability and evolvability of Pel production at the air-liquid interface (during pellicle formation) and on solid surfaces (during colony formation). Although Pel contributes to the developmental response to electron acceptor limitation in both biofilm formation regimes, we found variation in the exploitability of its production and necessity for competitive fitness between the two systems. The wild type showed a competitive advantage against a non-Pel-producing mutant in pellicles but no advantage in colonies. Adaptation to the pellicle environment selected for mutants with a competitive advantage against the wild type in pellicles but also caused a severe disadvantage in colonies, even in wrinkled colony centers. Evolution in the colony center produced divergent phenotypes, while adaptation to the colony edge produced mutants with clear competitive advantages against the wild type in this O2-replete niche. In general, the structurally heterogeneous colony environment promoted more diversification than the more homogeneous pellicle. These results suggest that the role of Pel in community structure formation in response to electron acceptor limitation is unique to specific biofilm models and that the facultative control of Pel production is required for PA14 to maintain optimum benefit in different types of communities.
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Taira, Even A., Talita M. S. Ventura, Luiza P. S. Cassiano, Cintia M. S. Silva, Tatiana Martini, Aline L. Leite, Daniela Rios, Ana Carolina Magalhães, and Marília Afonso Rabelo Buzalaf. "Changes in the Proteomic Profile of Acquired Enamel Pellicles as a Function of Their Time of Formation and Hydrochloric Acid Exposure." Caries Research 52, no. 5 (2018): 367–77. http://dx.doi.org/10.1159/000486969.
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Objective: Changes in the protein profile of acquired enamel pellicles (AEP) formed in vivo over different time periods were evaluated after the application of hydrochloric acid (HCl). Methods: Nine subjects were submitted to dental prophylaxis with pumice. After 3 or 120 min, the teeth were isolated with cotton rolls and 50 μL of 0.1 M HCl (pH 1.0), 0.01 M HCl (pH 2.0), or deionized water were applied on the buccal surface of the teeth for 10 s. The AEP was then collected using an electrode filter paper presoaked in 3% citric acid. After protein extraction, the samples were submitted to reverse-phase liquid chromatography coupled to mass spectrometry (nano LC-ESI-MS/MS). Label-free quantification was performed (Protein Lynx Global Service software). Results: A total of 180 proteins were successfully identified in the AEP samples. The number of identified proteins increased with the time of pellicle formation. Only 4 proteins were present in all the groups (isoforms of IgA, serum albumin, and statherin). The greatest number of proteins identified uniquely in one of the groups was obtained for the groups treated with HCl after 2 h of pellicle formation (approx. 50 proteins). Conclusion: Proteins resistant to removal by HCl, such as serum albumin and statherin, were identified even in the short-term AEP. In addition, 120-min pellicles present many proteins that are resistant to removal by HCl. This suggests an increase in protection against intrinsic acids with the time of pellicle formation, which should be evaluated in future studies.
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Gibbons, R. J., and D. I. Hay. "Adsorbed Salivary Acidic Proline-rich Proteins Contribute to the Adhesion of Streptococcus mutans JBP to Apatitic Surfaces." Journal of Dental Research 68, no. 9 (September 1989): 1303–7. http://dx.doi.org/10.1177/00220345890680090201.
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Experimental pellicles formed on hydroxyapatite (HA) beads from parotid or submandibular saliva promoted the adhesion of Streptococcus mutans JBP cells to a greater extent than did pellicles prepared from buffer; human plasma, or serum. The nature of the salivary components responsible was studied by the preparation of pellicles from fractions of parotid saliva obtained by chromatography on Trisacryl GF 2000 columns. Two groups of fractions promoted attachment of the organism. Components migrating in the high-molecular-weight mucin fraction were most effective, but a later-eluting fraction also possessed adhesion-promoting activity. Subfractionation of the latter material indicated that the adhesion-promoting activity was associated with the acidic proline-rich proteins (PRPs). Pellicles prepared from 10-20-μg/mL solutions of pure PRP-1 were effective in promoting attachment of S. mutans JBP cells. PRP-3 was less effective, while human salivary statherin, fibrinogen, fibronectin, type 1 collagen, and the amino-terminal tryptic peptide derived from PRP-1 were ineffective. The quantities of 150-residue and 106-residue PRPs and of statherin, which became incorporated into experimental pellicles prepared from saliva, were estimated with use of radiolabeled protein tracers. The data obtained suggest that these proteins compete for similar binding sites on HA, and that their ratios in saliva would therefore influence the quantity of the larger PRPs that become incorporated into the pellicle. Such competition may contribute to the variability observed in the adhesion-promoting activities of different saliva samples.
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van der Mei, H. C., M. Rustema-Abbing, G. M. Bruinsma, B. Gottenbos, and H. J. Busscher. "Sequence of Oral Bacterial Co-adhesion and Non-contact Brushing." Journal of Dental Research 86, no. 5 (May 2007): 421–25. http://dx.doi.org/10.1177/154405910708600506.
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Non-contact plaque removal offers advantages in interproximal spaces, fissures, and pockets. It requires the generation of strong fluid flows and the inclusion of air bubbles to become effective. A pair of co-adhering streptococci and actinomyces has been used previously to demonstrate non-contact removal by sonic brushing. Here we determined the influence of the sequence of co-adhesion of streptococci and actinomyces on non-contact removal from a salivary pellicle by rotary and sonic brushing. After bacterial adhesion, pellicles were brushed in a wet and immersed state, with a distance up to 4 mm to the bristle tips. Bacteria adhering to pellicles from the sequence streptococci followed by actinomyces appeared more difficult to remove and left more large co-aggregates than from the sequence actinomyces followed by streptococci. At contact, rotary and sonic brushing performed equally well in bacterial removal, while at 4 mm, both had lost some efficacy.
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Zaini, Paulo A., Noah G. Feinberg, Filipa S. Grilo, Houston J. Saxe, Michelle R. Salemi, Brett S. Phinney, Carlos H. Crisosto, and Abhaya M. Dandekar. "Comparative Proteomic Analysis of Walnut (Juglans regia L.) Pellicle Tissues Reveals the Regulation of Nut Quality Attributes." Life 10, no. 12 (November 27, 2020): 314. http://dx.doi.org/10.3390/life10120314.
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Walnuts (Juglans regia L.) are a valuable dietary source of polyphenols and lipids, with increasing worldwide consumption. California is a major producer, with ’Chandler’ and ’Tulare’ among the cultivars more widely grown. ’Chandler’ produces kernels with extra light color at a higher frequency than other cultivars, gaining preference by growers and consumers. Here we performed a deep comparative proteome analysis of kernel pellicle tissue from these two valued genotypes at three harvest maturities, detecting a total of 4937 J. regia proteins. Late and early maturity stages were compared for each cultivar, revealing many developmental responses common or specific for each cultivar. Top protein biomarkers for each developmental stage were also selected based on larger fold-change differences and lower variance among replicates, including proteins for biosynthesis of lipids and phenols, defense-related proteins and desiccation stress-related proteins. Comparison between the genotypes also revealed the common and specific protein repertoires, totaling 321 pellicle proteins with differential abundance at harvest stage. The proteomics data provides clues on antioxidant, secondary, and hormonal metabolism that could be involved in the loss of quality in the pellicles during processing for commercialization.
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Sobchenko, V. V., V. A. Zhaivoronok, and H. O. Sobchenko. "Rottenstone as a basis for obtaining geopolymer material." Кераміка: наука і життя, no. 3(48) (October 12, 2020): 18–22. http://dx.doi.org/10.26909/csl.3.2020.3.
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The possibility of obtaining perspective geopolymer materials for use in the building industry was shown. Geopolymer materials are used with such advantages as high strength, density, water resistance, heat and heat resistance, environmental friendliness, durability, and high corrosion resistance. The raw material is rottenstone, a rock with a high silica content, which is widespread in Ukraine. Rottenstone is characterized by a ratio of SiО2:Al2O3 equal to 16… 20, which provides a high strength of the final material. It was indicated that physico-chemical processes that take place during polymerization are similar to those that take place in thin pellicles of the released SiO2 gel, cements the particles, and thus promotes hardening. As a result of the treatment of raw materials with alkali solution at temperatures of 80-120 °С, a monolithic solid material of olive color with a density of 1200-1700 kg/m3, humidity of 30-45% was formed. Precipitations were observed on the surface of the material due to the presence of non-chemically bound sodium and potassium cations in the pores of the geopolymer. When dried, they diffuse to the surface of the geopolymer and are subjected to atmospheric carbonization. It was indicated that in order to obtain a high-strength geopolymer material, it is necessary to carry out final heat treatment at temperatures close to 100 °С. The behavior of geopolymer samples aged over time at room temperature during their heating was investigated. The samples of the material are melted due to the presence of Na2O×SiО2×8Н2O and Na2O×SiО2×5Н2O crystal hydrates, which melt at relatively low temperatures at 48°С and 72°С, respectively. The formation of building geopolymer materials should take into account this melting by placing it in molds was concluded. Indicators of moisture loss at a temperature of about 100°С depending on the heat treatment time were obtained.
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Sung, Nackmoon, and Michael T. Collins. "Variation in Resistance of Mycobacterium paratuberculosis to Acid Environments as a Function of Culture Medium." Applied and Environmental Microbiology 69, no. 11 (November 2003): 6833–40. http://dx.doi.org/10.1128/aem.69.11.6833-6840.2003.
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ABSTRACT Acid resistance of Mycobacterium paratuberculosis was examined as a function of growth conditions (i.e., in vitro growth medium and pH). M. paratuberculosis was cultured in either fatty acid-containing medium (7H9-OADC) or glycerol-containing medium (WR-GD or 7H9-GD) at two culture pHs (pHs 6.0 and 6.8). Organisms produced in these six medium and pH conditions were then tested for resistance to acetate buffer at pHs 3, 4, 5, and 6 at 20°C. A radiometric culture method (BACTEC) was used to quantify viable M. paratuberculosis cell data at various acid exposure times, and D values (decimal reduction times, or the times required to kill a 1-log10 concentration of bacteria) were determined. Soluble proteins of M. paratuberculosis grown under all six conditions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to identify proteins that may be associated with acid resistance or susceptibility. The culture medium affected growth rate and morphology: thin floating sheets of cells were observed in 7H9-OADC versus confluent, thick, waxy, and wrinkled pellicles in WR-GD. Culture medium pH affected growth rate (which was highest at pH 6.0), but it had little or no effect on D values for M. paratuberculosis at any test pH. When grown in 7H9-OADC, M. paratuberculosis was more acid resistant at all test pHs (higher D values) than when grown in WR-GD. Glycerol appeared to be the culture medium component most responsible for lower levels of M. paratuberculosis acid resistance. When glycerol was substituted for OADC in the 7H9 medium, D values were significantly lower than those of 7H9-OADC-grown M. paratuberculosis and were approximately the same as those for M. paratuberculosis grown in WR-GD medium. Comparison of the SDS-PAGE protein profiles for M. paratuberculosis cultures grown in 7H9-OADC, WR-GD, or 7H9-GD medium revealed that increased expression of 34.2- and 14.0-kDa proteins was associated with higher levels of acid resistance of M. paratuberculosis grown in 7H9-OADC medium and that 56.6- and 41.3-kDa proteins were associated with lower levels of acid resistance. This is the first report showing that in vitro culture conditions significantly affect growth characteristics, acid resistance, and protein expression of M. paratuberculosis, and the results emphasize the importance of culture conditions for in vitro susceptibility studies.
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Imaizumi, Naoya, Toshitsugu Sakurai, Masatsugu Hirota, Tohru Hayakawa, and Chikahiro Ohkubo. "Analysis of the Effect on Denture Base Metal of Cleaning with Denture Cleanser Using the Quartz Crystal Microbalance Method." Hygiene 1, no. 3 (December 3, 2021): 129–39. http://dx.doi.org/10.3390/hygiene1030012.
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Denture plaque control for the prevention of aspiration pneumonia is very important. The pellicle is the major cause of denture plaque adhesion. Few basic studies have evaluated the effectiveness of denture cleansers for pellicles composed of salivary proteins. The adhesion of salivary proteins formed on denture base metal and the removal rate were quantitatively analyzed using the QCM method after denture cleanser injection. This is the first study to compare the cleaning effects of denture cleanser on denture base metal using the QCM method. Au and Ti sensors were employed as the denture base metals. Albumin was used for the adsorption of salivary proteins. The results showed that no significant difference was found between Au and Ti in the amounts of albumin adsorbed, and the rate of albumin removal from Ti was significantly higher than that of Au. In this study, the cleaning effectiveness of denture cleanser was confirmed based on the adsorbed amount and the removal rate of salivary proteins adsorbed onto denture base metals. Thus, the QCM method was suggested to be a useful tool for removing the effects of salivary proteins from denture cleaning agents on denture base metal.
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Liu, Yong, Ting Lu, Zhuo Sun, Daniel H. C. Chua, and Likun Pan. "Ultra-thin carbon nanofiber networks derived from bacterial cellulose for capacitive deionization." Journal of Materials Chemistry A 3, no. 16 (2015): 8693–700. http://dx.doi.org/10.1039/c5ta00435g.
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Watanabe-Saito, Fumie, Youji Nakagawa, Munekazu Kishimoto, Masashi Hisamoto, and Tohru Okuda. "Influence of wine components on pellicle formation by pellicle-forming yeasts." OENO One 55, no. 3 (September 28, 2021): 363–75. http://dx.doi.org/10.20870/oeno-one.2021.55.3.4730.
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This study aimed to clarify differences in susceptibility to red wine pellicle formation by pellicle-forming yeasts between two wine grape cultivars and to investigate wine components affecting pellicle formation. Twenty wines each of Muscat Bailey A (MBA) and Merlot (MR), the major grape cultivars of Japanese red wine, were used. Pellicle formation occurred more often in MBA wines than in MR wines, and almost all MBA wine surfaces were covered with pellicle after incubation for five days. Principal component analysis revealed the relationships between pellicle formation and the concentrations of ethanol, phenolics and tannins. The mean concentration of tannins in the pellicle MR wines (436 mg/L) was significantly lower than that in the non-pellicle MR wines (660 mg/L). Furthermore, the mean concentration of tannins in MBA wines (139 mg/L) was also significantly lower than that in MR wines (570 mg/L). Wine grape cultivar having a low concentration of tannins may be highly susceptible to pellicle formation by pellicle-forming yeasts during winemaking.
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Bradway, S. D., E. J. Bergey, F. A. Scannapieco, N. Ramasubbu, S. Zawacki, and M. J. Levine. "Formation of salivary-mucosal pellicle: the role of transglutaminase." Biochemical Journal 284, no. 2 (June 1, 1992): 557–64. http://dx.doi.org/10.1042/bj2840557.
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The present investigation was carried out to identify salivary components of mucosal pellicles in vivo and explore further the mechanism of interaction between salivary molecules and buccal epithelial cells. By using specific antisera and immunoprotein blotting, high-(MG1) and low-(MG2) molecular-mass salivary mucins, amylase, salivary cystatins and proline-rich proteins were detected within mucosal pellicle in vivo. In addition, the data indicated that the mucins and proline-rich proteins could be cleaved into lower-molecular-mass products, whereas the proline-rich proteins could also be cross-linked into higher-molecular-mass complexes. The role of buccal epithelial cell transglutaminase in these interactions was further studied by utilizing purified iodinated amylase, neutral cystatin SN and acidic proline-rich proteins 1 and 3 (APRP1 and 3). After incubation with buccal epithelial cells in vitro 125I-labelled APRPs appeared to undergo a greater degree of cross-linking than 125I-labelled cystatin SN, as determined by SDS/PAGE/autoradiography. Amylase did not appear to be cross-linked at all. Recovery of 125I-labelled APRPs and 125I-labelled cystatin SN with epithelial cell envelopes after repeated extraction suggested that both molecules were cross-linked to envelope proteins, but that 125I-labelled APRPs were cross-linked to a greater degree than 125I-labelled cystatin SN. Cross-linking in buccal epithelial cell preparations was inhibited by an excess of methylamine hydrochloride, a transglutaminase substrate. In a further assessment of amylase, cystatin and APRPs as transglutaminase substrates, only APRP3 and a partially purified preparation of APRPs acted as an amine acceptor for the cross-linking of [14C]methylamine by purified transglutaminase, as determined by SDS/PAGE/fluorography. This reaction was completely inhibited by excess EDTA. The combined data from this study suggest that during mucosal pellicle formation multiple components of saliva adsorb to buccal epithelial cell surfaces, and that, within this group, selected components are enzymically cross-linked by an epithelial transglutaminase and/or proteolytically cleaved into smaller fragments.
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Jarrell, Jill, Namrata Walia, Diana Nemergut, Amar Agadi, and Joan Bennett. "Inoculation, Growth and Bactericidal Effects of Three Kombucha Cultures." Microbiology Research 13, no. 1 (February 18, 2022): 128–36. http://dx.doi.org/10.3390/microbiolres13010010.
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Kombucha, a domesticated consortium of several microorganisms grown on sugared tea, has been valued as a nutritive health aid for over a millennium. In this study, three cultures of kombucha were obtained from diverse sources. Different inoculation methods were compared, and the wet and dry weights of the nascent pellicles were measured when cultured on several carbon sources. In addition, the anti-bacterial properties of the fermented kombucha teas were tested against Escherichia coli and Staphylococcus epidermis. Inoculation with macerated pellicles gave the fastest kombucha growth. The best carbon sources for growth of the nascent kombucha pellicles were sucrose, glucose, and fructose. On maltose, galactose, and lactose, not only did the kombucha pellicles grow poorly but 25% were also contaminated by common airborne molds. Good growth of the kombucha cultures was correlated with low pH of the fermented tea. Antibacterial effects of concentrated fermented teas and vinegar were similar to those of 1 mmol ampicillin against Escherichia coli or 0.01 mmol penicillin against Staphylococcus epidermis. When the pH of concentrated kombucha teas was neutralized, their bactericidal effects were no better than unfermented controls.
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Tiedtke, A. "Isolation of pure pellicles containing intact basal bodies of Tetrahymena pyriformis." Journal of Cell Science 77, no. 1 (August 1, 1985): 155–65. http://dx.doi.org/10.1242/jcs.77.1.155.
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A new procedure for mass isolation of pure pellicles containing intact basal bodies of Tetrahymena pyriformis is reported. The success of the procedure depends on the elimination of the sticky mucocyst contents before fractionation of the cells, which is induced by Alcian Blue 8GS. Under appropriate ionic conditions greater than 95% of the cells are able to form a capsule by simultaneous extrusion of all mature mucocysts. About 50% of these cells are able to escape from their capsules, which are now devoid of mature mucocysts. These cells are separated from the empty capsules and encapsulated cells by passage through layers of gauze of 10 microns pore size. The fractionation of mucocyst-free cells in homogenization buffer yields pure pellicles, which are retained when the homogenate is sieved through steel sieves of 5 microns pore size. Electron-microscopic controls show that the isolated pellicles are not contaminated with subcellular particles. Cells homogenized in the presence of low concentrations of Triton X-100 yield pellicles consisting of the known cell-surface-associated cytoskeletal elements, together with basal bodies. The cilia are detached just above the kinetosomal plate. The basal bodies of isolated pellicles are obviously undamaged, since all the known structures of native basal bodies are preserved. Even the granular matrix, a labile structure in the lumen of the basal body that probably contains RNA, is preserved.
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Vornicescu, Doru, Katerina Solanska, Ioana Demetrescu, Matthias Frentzen, and Michael Keusgen. "Dynamics of Dental Pellicle Formation - In Vitro Analysis of Time Dependant Binding Behavior by Surface Plasmon Resonance and the Influence of Oral Therapeutics." Key Engineering Materials 415 (September 2009): 77–80. http://dx.doi.org/10.4028/www.scientific.net/kem.415.77.
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: The pellicle on oral surfaces represents a central interface for the formation of biofilms. Among other things it causes the first adsorption of bacteria. The dynamics of pellicle formation, on tooth surfaces and the influence of oral therapeutics on the pellicle structure are fairly unknown. With the method of surface plasmon resonance (SPR), the formation of salivary pellicle structures on hydroxylapatite (HAP) surfaces covering a very thin (~50nm) layer gold on a glass prism was recorded in real time without labeling or destruction. As pellicle forming substrates natural pooled human saliva (NS) and artificial saliva (AS) were used. To simulate the influence of therapeutic additives on the dynamic of the pellicle forming process, a chlorhexidine preparate (Chlorhexamed Fluid® CHX) on two different concentrations was selected. The binding behavior of a NS and a preparation in terms of an AS were compared. The layer was largely stable against rinsing with buffer. The application of CHX preparations in two different concentrations as an example of an oral therapeutic additive revealed a complex dynamic of adsorption. CHX did not lead to any visible destruction of the pellicle. The introduced method is an excellent tool to illustrate the dynamic effects of pellicle formation or pellicle reorganization by measuring the increase or decrease of the SPR signal in real time.
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Siqueira, W. L., H. C. Margolis, E. J. Helmerhorst, F. M. Mendes, and F. G. Oppenheim. "Evidence of Intact Histatins in thein vivoAcquired Enamel Pellicle." Journal of Dental Research 89, no. 6 (March 29, 2010): 626–30. http://dx.doi.org/10.1177/0022034510363384.
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Parkar, S. G., S. Eady, M. Cabecinha, and M. A. Skinner. "Consumption of apple-boysenberry beverage decreases salivary Actinomyces naeslundii and their adhesion in a multi-species biofilm model." Beneficial Microbes 8, no. 2 (April 26, 2017): 299–307. http://dx.doi.org/10.3920/bm2016.0061.
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We hypothesised that consumption of beverage rich in both fibre and polyphenols, rather than each bioactive alone, will modulate populations of selected salivary bacteria, and their adhesion characteristics and that some of these effects may be due to the anti-microbial activity of the beverage bioactives. We investigated the effect of 4 weeks’ consumption of beverages, rich in apple fibre, boysenberry polyphenols, or both on salivary bacteria in healthy subjects. In this placebo-controlled crossover study, saliva samples were collected at the beginning and end of each treatment period, and used for qPCR quantitation of Lactobacillus spp., Actinomyces naeslundii and Streptococcus mutans. The counts of salivary A. naeslundii decreased after the consumption of the apple-boysenberry beverage (P<0.05, Student’s t-test). We also examined the effect of the subjects’ saliva on bacterial adhesion using a mixed species biofilm model. The salivary pellicles prepared before and after each treatment were inoculated with laboratory strains of A. naeslundii, Lactobacillus rhamnosus and S. mutans and tested for biofilm formation. The post appleboysenberry beverage salivary pellicle significantly decreased the adhesion of A. naeslundii at the end of both 3 and 24 h, in the in vitro biofilm. A 1/16 dilution of the apple-boysenberry beverage itself decreased the proliferation of test strains of A. naeslundii and S. mutans by 51 and 55%, respectively (P<0.005), indicating the antimicrobial activity of its bioactives. This study demonstrated that consumption of apple-boysenberry beverage, rather than apple or the boysenberry beverage alone or the placebo, decreased salivary A. naeslundii and their adhesion under laboratory conditions. These changes are factors that influence oral microecology and potentially oral health.
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Subtaweesin, Chayut, Wannipa Woraharn, Siriporn Taokaew, Nadda Chiaoprakobkij, Amornpun Sereemaspun, and Muenduen Phisalaphong. "Characteristics of Curcumin-Loaded Bacterial Cellulose Films and Anticancer Properties against Malignant Melanoma Skin Cancer Cells." Applied Sciences 8, no. 7 (July 20, 2018): 1188. http://dx.doi.org/10.3390/app8071188.
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Curcumin-loaded bacterial cellulose films were developed in this study. Curcumin was absorbed into never-dried bacterial cellulose pellicles by 24-h immersion in solutions of curcumin in the range of 0.2–1.0 mg /mL. The curcumin-loaded bacterial cellulose pellicles were then air-dried and characterized. The mechanical properties of curcumin-loaded bacterial cellulose films, particularly the stretching properties, appeared to be lower than those of bacterial cellulose film. This was especially evident when the loading concentration of curcumin was higher than 0.4 mg/mL. Fourier-transform infrared spectroscopy analysis indicated an interaction between bacterial cellulose microfibrils and curcumin. Controlled release of curcumin was achieved in buffer solutions containing Tween 80 and methanol additives, at pH 5.5 and 7.4. Curcumin-loaded bacterial cellulose films prepared with curcumin solutions at concentrations of 0.5 and 1.0 mg/mL displayed antifungal activities against Aspergillus niger. They also exhibited anticancer activity against A375 malignant melanoma cells. No significant cytotoxic effect was observed against normal dermal cells, specifically, human keratinocytes and human dermal fibroblasts.
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Cheaib, Zeinab, Ekaterina Rakmathulina, Adrian Lussi, and Sigrun Eick. "Impact of Acquired Pellicle Modification on Adhesion of Early Colonizers." Caries Research 49, no. 6 (2015): 626–32. http://dx.doi.org/10.1159/000442169.
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New preventive approaches against dental erosion caused by acidic drinks and beverages include fortification of beverages with natural polymers. We have shown that the mixture of casein and mucin significantly improved the erosion-inhibiting properties of the human pellicle layer. This study aimed to investigate the effect of pellicle modification by casein, mucin and a casein-mucin mixture on the adhesion of early bacterial colonizers. Test specimens of human tooth enamel were prepared, covered with saliva and coated with 0.5% aqueous (aq.) casein, 0.27% aq. mucin or with 0.5% aq. casein-0.27% aq. mucin, after which the adhesion of Streptococcus gordonii, Streptococcus oralis, and Actinomyces odontolyticus was measured after incubation for 30 min and 2 h. log10 colony-forming units were compared by nonparametric tests. All three bacterial strains adhered in higher number to pellicle-coated enamel than to native enamel. The protein modifications of pellicle all decreased the counts of adhering bacteria up to 0.34 log10/mm2, the most efficient being the casein-mucin mixture. In addition to the recently shown erosion-reducing effect by casein-mucin, modification of the pellicle may inhibit bacterial adherence compared to untreated human pellicle.
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Wi, Seong Ju, Yong Ju Jang, Haneul Kim, Kyeongjae Cho, and Jinho Ahn. "Investigation of the Resistivity and Emissivity of a Pellicle Membrane for EUV Lithography." Membranes 12, no. 4 (March 26, 2022): 367. http://dx.doi.org/10.3390/membranes12040367.
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A pellicle is a thin membrane structure that protects an extreme ultraviolet (EUV) mask from contamination during the exposure process. However, its limited transmittance induces unwanted heating owing to the absorption of EUV photons. The rupture of the EUV pellicle can be avoided by improving its thermal stability, which is achieved by improving the emissivity of the film. However, the emissivity data for thin films are not easily available in the literature, and its value is very sensitive to thickness. Therefore, we investigated the dependence of emissivity on structural parameters, such as thickness, surface roughness, and grain size. We found a correlation between resistivity and emissivity using theoretical and experimental approaches. By changing the grain size of the Ru thin film, the relationship between resistivity and emissivity was experimentally verified and confirmed using the Lorentz–Drude model. Finally, we present a method to develop an EUV pellicle with better thermal stability that can withstand high-power EUV light sources.
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Scher, Keren, Ute Romling, and Sima Yaron. "Effect of Heat, Acidification, and Chlorination on Salmonella enterica Serovar Typhimurium Cells in a Biofilm Formed at the Air-Liquid Interface." Applied and Environmental Microbiology 71, no. 3 (March 2005): 1163–68. http://dx.doi.org/10.1128/aem.71.3.1163-1168.2005.
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ABSTRACT Bacterial biofilms have great significance for public health, since biofilm-associated microorganisms exhibit dramatically decreased susceptibility to antimicrobial agents and treatments. To date most attention has focused on biofilms that arise from the colonization of solid-liquid or solid-air interfaces. It is of interest that colonization of the interface between air and liquid, which can be selectively advantageous for aerobic or facultative aerobic bacteria, has been rarely studied, although it may present a major problem in industrial aquatic systems. In this work we investigated the role of a biofilm at the interface between air and liquid (pellicle) in the susceptibility of Salmonella enterica serovar Typhimurium to stress conditions. For a control we used a mutant that had lost its ability to synthesize cellulose and thin aggregative fimbriae and thus did not produce the pellicle. Resistance of bacteria from the pellicle to heat, acidification, and chlorination was compared to resistance of planktonic cells from the logarithmic and stationary phases of growth. Pellicle cells were significantly more resistant to chlorination, and thus the surrounding matrix conferred protection against the reactive sodium hypochlorite. However, the stress management of pellicle cells in response to heat and low pH was not enhanced compared to that of stationary-phase cells. A long-period of incubation resulted in endogenous hydrolysis of the pellicle matrix. This phenomenon provides a potential new approach to combat microbial cells in biofilms.
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EKLUND, M. W., M. E. PETERSON, F. T. POYSKY, R. N. PARANJPYE, and G. A. PELROY. "Control of Bacterial Pathogens during Processing of Cold-Smoked and Dried Salmon Strips." Journal of Food Protection 67, no. 2 (February 1, 2004): 347–51. http://dx.doi.org/10.4315/0362-028x-67.2.347.
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Microbiological and chemical changes were determined during the smoking and drying of salmon strips processed at 29 to 31°C for 4 days at a facility in Alaska in 1993. During the process, Staphylococcus aureus populations increased to more than 105 CFU/g after 2 to 3 days of processing. Subsequent laboratory studies showed that a pellicle (dried skinlike surface) formed rapidly on the strips when there was rapid air circulation in the smokehouse and that bacteria embedded in or under the pellicle were able to grow even when heavy smoke deposition occurred. Under these conditions, an inoculum of 26 CFU/g of S. aureus increased to 105 CFU/g after 3 days of processing. Elimination of preprocess drying and reduction in air flow during smoking resulted in smoke deposition before pellicle formation and enabled the product to reach levels of water-phase salt and water activity that inhibit the growth of S. aureus and Listeria monocytogenes. In 1994, these modifications were then applied during processing at an Alaskan facility, and S. aureus could not be detected in the finished product. L. monocytogenes was detected in the raw product area, on the processing tables, and on the raw salmon strips, but it was not detected in the finished product when the smoke was applied before pellicle formation.
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Dergham, Yasmine, Pilar Sanchez-Vizuete, Dominique Le Coq, Julien Deschamps, Arnaud Bridier, Kassem Hamze, and Romain Briandet. "Comparison of the Genetic Features Involved in Bacillus subtilis Biofilm Formation Using Multi-Culturing Approaches." Microorganisms 9, no. 3 (March 18, 2021): 633. http://dx.doi.org/10.3390/microorganisms9030633.
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Surface-associated multicellular assemblage is an important bacterial trait to withstand harsh environmental conditions. Bacillus subtilis is one of the most studied Gram-positive bacteria, serving as a model for the study of genetic pathways involved in the different steps of 3D biofilm formation. B. subtilis biofilm studies have mainly focused on pellicle formation at the air-liquid interface or complex macrocolonies formed on nutritive agar. However, only few studies focus on the genetic features of B. subtilis submerged biofilm formation and their link with other multicellular models at the air interface. NDmed, an undomesticated B. subtilis strain isolated from a hospital, has demonstrated the ability to produce highly structured immersed biofilms when compared to strains classically used for studying B. subtilis biofilms. In this contribution, we have conducted a multi-culturing comparison (between macrocolony, swarming, pellicle, and submerged biofilm) of B. subtilis multicellular communities using the NDmed strain and mutated derivatives for genes shown to be required for motility and biofilm formation in pellicle and macrocolony models. For the 15 mutated NDmed strains studied, all showed an altered phenotype for at least one of the different culture laboratory assays. Mutation of genes involved in matrix production (i.e., tasA, epsA-O, cap, ypqP) caused a negative impact on all biofilm phenotypes but favored swarming motility on semi-solid surfaces. Mutation of bslA, a gene coding for an amphiphilic protein, affected the stability of the pellicle at the air-liquid interface with no impact on the submerged biofilm model. Moreover, mutation of lytF, an autolysin gene required for cell separation, had a greater effect on the submerged biofilm model than that formed at aerial level, opposite to the observation for lytABC mutant. In addition, B. subtilis NDmed with sinR mutation formed wrinkled macrocolony, less than that formed by the wild type, but was unable to form neither thick pellicle nor structured submerged biofilm. The results are discussed in terms of the relevancy to determine whether genes involved in colony and pellicle formation also govern submerged biofilm formation, by regarding the specificities in each model.
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Steinberg, D., D. Beeman, and W. H. Bowen. "Interactions of Delmopinol with Constituents of Experimental Pellicle." Journal of Dental Research 71, no. 11 (November 1992): 1797–802. http://dx.doi.org/10.1177/00220345920710110601.
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The prolonged retention of an effective chemotherapeutic agent on oral surfaces and in dental plaque aids in plaque control. The objective of this study was to investigate interactions between delmopinol, a morpholinoethanol derivative, and experimental pellicle. Hydroxyapatite beads were coated with different constituents of pellicle (e.g., saliva, carbohydrates, cell-free enzymes, and bacteria). Delmopinol demonstrated a higher affinity for saliva-coated hydroxyapatite (sHA) and for experimental pellicle coated with in situ-synthesized glucans than for untreated hydroxyapatite. High-molecular-weight (MW) dextran but not low-MW dextran interfered with the adsorption of delmopinol to sHA. Delmopinol did not compete with dextran for the same binding sites on sHA, nor did it compete with saliva for the same binding sites on untreated hydroxyapatite. Delmopinol inhibited the activity of cell-free fructosyltransferase adsorbed onto sHA. In addition, synthesis of glucans by Streptococcus mutans adsorbed onto sHA was significantly reduced in the presence of delmopinol.
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Baumann, Tommy, Christoph Schmidt, and Thiago Saads Carvalho. "Pellicle Modification with Casein and Mucin Does Not Affect Surface Loss from Erosion and Abrasion." Caries Research 54, no. 5-6 (2020): 509–16. http://dx.doi.org/10.1159/000510699.
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<b><i>Aim:</i></b> A combination of the proteins casein and mucin is known to modify the salivary pellicle and improve its protection of the underlying enamel from erosion. It is so far not known if this protection is confined solely to erosion, or if it also extends to abrasion, and this in vitro study aimed at investigating this question. <b><i>Methods:</i></b> A total of 72 human enamel specimens were prepared and randomly assigned to four groups: pellicle (P), casein/mucin (CM), pellicle + casein/mucin (PCM), and control (Ctrl). Each specimen underwent five cycles, each cycle consisting of a pellicle/treatment part, an erosion part (3 min in 1% citric acid, pH 3.6, 25°C, 70 rpm), and an abrasion part (50 toothbrush strokes within 25 s in toothpaste slurry with a 200-g load). The pellicle/treatment part consisted of 2 h of incubation in whole human saliva for group P, 2 h of incubation (25°C, 70 rpm) in a protein mixture of 1% casein and 0.27% mucin for group CM, and 2 h of incubation in saliva followed by 2 h of incubation in the protein mixture for group PCM. The fourth group (Ctrl) served as the control and was kept in a humid chamber without saliva or protein treatment. The enamel surfaces were scanned with an optical profilometer initially and after the final cycle, and surface loss was analyzed. Furthermore, the surface microhardness (SMH) was measured initially, after each pellicle/treatment part and each erosion cycle, and after the final abrasion cycle. The results were analyzed with Kruskal-Wallis and Wilcoxon tests with Bonferroni corrections. <b><i>Results:</i></b> The different treatments did not show differences in surface loss and therefore did not protect enamel from surface loss by abrasion. Nonetheless, we observed differences in the SMH values, namely the Ctrl group being significantly softer than the experimental groups. <b><i>Conclusion:</i></b> The observed differences in SMH suggest that a different abrasion protocol could lead to differences in surface loss, and further investigation of whether and under which conditions pellicle modification leads to increased resistance to abrasion remains worthwhile.
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Mynenivenkatasatya, Srinivas Rao, Howard Wang, William Cooley, Esmeralda Garcia-Smith, Jaiprakash Shewale, and James Ratcliff. "Effectiveness of a Novel Dentifrice Containing Stabilized Chlorine Dioxide, Sarkosyl, and Sodium Fluoride." Dentistry Journal 8, no. 4 (October 27, 2020): 122. http://dx.doi.org/10.3390/dj8040122.
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This in vitro study evaluated the effectiveness of a novel dentifrice containing stabilized chlorine dioxide, sodium lauroyl sarcosinate (sarkosyl), and sodium fluoride in enhancing enamel fluoride uptake, remineralization, pellicle cleaning and inhibiting biofilm regrowth. Remineralization was measured by fluoride uptake and surface microhardness assessment tests. Artificial stains were removed and scored based on pellicle cleaning ratio. Biofilm regrowth was measured by counting colonies on the agar plates. All studies were conducted using bovine teeth specimens. The efficacy of Toothpaste C (CloSYS anticavity toothpaste) was compared with United States Pharmacopoeia Reference Dentifrice, Toothpaste B (discontinued CloSYS anticavity toothpaste formulation) and leading commercial toothpastes. The enamel fluoride uptake and remineralization by Toothpaste C was 96.1% to 303.3% and 38.0% to 102.4% higher than the tested toothpastes, respectively. The mean pellicle cleaning ratio of Toothpaste C was similar to American Dental Association Reference Material. Toothpaste C had a significant reduction in regrowth of the oral polymicrobial biofilm compared to the control. All tested toothpastes contained 0.24% sodium fluoride. Toothpaste C exhibited significantly superior performance towards fluoride uptake and remineralization compared to the tested toothpastes. Therefore, toothpaste ingredients other than sodium fluoride accounted for the enhanced fluoride uptake and remineralization.
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Cvetkovic, Dragoljub, and Sinisa Markov. "Producing kombucha beverage from winter savory (Satureja montana L.) tea inoculated by pellicle." Acta Periodica Technologica, no. 37 (2006): 119–30. http://dx.doi.org/10.2298/apt0637119c.
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The work is concerned with the possibility of preparing kombucha beverage from sweetened winter savory (local name Rtanj tea) inoculated with the pellicle in a quantity of 2 -51 in the vessels (glass containers) volume of 2 - 6 l. It was found that the process lasts a few days (2 - 5) longer than the traditional process of biotransformation of black tea into kombucha. It was also concluded that the rate of the process depends mostly on the volume container: medium ratio. In the subsequent kombucha fermentations the metabolic activity of the yeast and acetic fermentation cells did not change. The rate of the process was not influenced by the physiological state of the cells in the pellicle with the capacities larger than 31.
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Kensche, A., S. Pötschke, C. Hannig, G. Richter, W. Hoth-Hannig, and M. Hannig. "Influence of Calcium Phosphate and Apatite Containing Products on Enamel Erosion." Scientific World Journal 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/7959273.
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For the purpose of erosion prevention the present study aimed to compare the efficacy of two biomimetic products and a fluoride solution to optimize the protective properties of the pellicle. After 1 min ofin situpellicle formation on bovine enamel slabs, 8 subjects adopted CPP-ACP (GC Tooth Mousse), a mouthwash with hydroxyapatite microclusters (Biorepair), or a fluoride based mouthwash (elmex Kariesschutz) for 1 min each. Afterwards, samples were exposed in the oral cavity for 28 min. Native enamel slabs and slabs exposed to the oral cavity for 30 min without any rinse served as controls. After oral exposure, slabs were incubated in HCl (pH values 2, 2.3, and 3) for 120 s and kinetics of calcium and phosphate release were measured photometrically; representative samples were evaluated by SEM and TEM. The physiological pellicle reduced demineralization at all pH values; the protective effect was enhanced by fluoride. The biomimetic materials also reduced ion release but their effect was less pronounced. SEM indicated no layer formation after use of the different products. However, TEM confirmed the potential accumulation of mineral components at the pellicle surface. The tested products improve the protective properties of thein situpellicle but not as effectively as fluorides.
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Hao, Jianjun J., Huawei Liu, Irwin Ronaldo Donis-Gonzalez, Xiao Hong Lu, A. Daniel Jones, and Dennis W. Fulbright. "Antimicrobial Activity of Chestnut Extracts for Potential Use in Managing Soilborne Plant Pathogens." Plant Disease 96, no. 3 (March 2012): 354–60. http://dx.doi.org/10.1094/pdis-03-11-0169.
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Chestnut extracts were studied for antimicrobial activity against selected microorganisms, including plant pathogens. Chestnut extract on paper discs was applied to an agar medium to evaluate the inhibition to multiple microorganisms or the extract was added at various concentrations to a culture medium to evaluate the growth of target microorganisms. Chestnut type, tissue of plants (shell, pellicle, and leaf), extraction methods, and physical characteristics were studied to determine antimicrobial activity. Most test microorganisms were inhibited by the extracts at different effective concentrations for 50% growth inhibition (EC50). Pseudomonas fluorescens was the most sensitive (EC50 = 4.4 μg/μl), Phytophthora cambivora was one of the least inhibited (EC50 = 185 μg/μl), and Cryphonectria parasitica was not inhibited. Extracts of the Japanese × European chestnut (Castanea crenata × C. sativa) ‘Colossal’ showed a greater inhibition than those of wild trees of the Chinese species (C. mollissima). High temperature did not affect the inhibitory effect. Extracts from chestnut pellicle had the highest concentration of antimicrobial compound, compared with leaf and shell. The active fraction contained several substances with molecular masses consistent with one flavonol glycoside and several terpenoid substances. Pellicle and shell tissue reduced radish scab disease caused by Streptomyces scabies in the greenhouse.
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MAHONEY, NOREEN E., LUISA W. CHENG, and JEFFREY D. PALUMBO. "Effect of Blanching on Aflatoxin Contamination and Cross-Contamination of Almonds." Journal of Food Protection 83, no. 12 (July 21, 2020): 2187–92. http://dx.doi.org/10.4315/jfp-20-218.
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ABSTRACT Blanching of almonds was examined for reducing the aflatoxin content of contaminated nuts. Almonds with intact pellicles were spiked with aflatoxin B1 (AFB1) and blanched at 85°C. Following blanching, almond kernels and pellicles contained 20 and 19% of the spiked AFB1, respectively. The blanching water contained an additional 41% of the spiked AFB1. In a separate study, postblanching water was spiked with AFB1 and used for subsequent blanching of uncontaminated almonds. The resulting blanched kernels acquired 3.3% of the AFB1 from the spiked water, demonstrating a low level of cross-contamination from reused contaminated blanching water. The effect of the blanching temperature on partitioning of AFB1 from almonds to blanching water was significant at a 20-ppb spiking level, but not at 100 ppb. AFB1 levels that were unaccounted for in the mass balance of blanching components were presumed to be lost due to binding to water-solubilized almond components and were independent of pH and blanching time. Blanching reduced total aflatoxins in naturally contaminated almonds by 13 to 76%, depending on almond quality, as well as blanching time and temperature. These results indicate that the association between almond components and aflatoxin generated through mold contamination is more complex than in spiking experiments. HIGHLIGHTS
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Muhajir, Muhamad, Heru Suryanto, and Aisyah Larasati. "Effect of Alkalization on the Bacterial Cellulose Film Structure Produced Using the Pineapple Waste." Key Engineering Materials 851 (July 2020): 92–96. http://dx.doi.org/10.4028/www.scientific.net/kem.851.92.
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Bacterial cellulose is natural polymers materials produced by Acetobacter xylinum with attractive physical properties because they are ordinary and uniform in structure. An alternative of cellulose from renewable source with more effective results to produce bacterial cellulose fibers. For this reason, the purpose of this paper is to show the effect of alkalization process on the bacterial cellulose film structure. The methods were the synthesis of bacterial cellulose using the extracts of pineapple waste. The pellicle product was treated using in the concentration of 0%, 1%, 5% and 10% then bacterial fiber films obtained from drying process of treated pellicle. Furthermore, the XRD and FTIR of bacterial cellulose were observed. The results of the structure of bacterial cellulose film was changed after a process in a high concentration of NaOH.
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Siqueira, W. L., W. Custodio, and E. E. McDonald. "New Insights into the Composition and Functions of the Acquired Enamel Pellicle." Journal of Dental Research 91, no. 12 (September 26, 2012): 1110–18. http://dx.doi.org/10.1177/0022034512462578.
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The acquired enamel pellicle (AEP) is a thin acellular film that forms on tooth surfaces upon exposure to the oral environment. It consists predominantly of salivary proteins, but also includes non-salivary-derived proteins, carbohydrates, and lipids. Since it is the interface between teeth and the oral environment, the AEP plays a key role in the maintenance of oral health by regulating processes including lubrication, demineralization, and remineralization and shaping the composition of early microbial flora adhering to tooth surfaces. Knowledge of the 3D structure of the AEP and how that correlates with its protective functions may provide insight into several oral pathological states, including caries, erosion, and periodontal disease. This review intends to update readers about the latest discoveries related to the formation, ultrastructure, composition, and functions of the AEP, as well as the future of pellicle research, with particular emphasis on the emerging role of proteomic and microscopy techniques in oral diagnosis and therapeutics.
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Lee, Bor-Shiunn, Yu-Jia Chen, Ta-Chin Wei, Tien-Li Ma, and Che-Chen Chang. "Comparison of Antibacterial Adhesion When Salivary Pellicle Is Coated on Both Poly(2-hydroxyethyl-methacrylate)- and Polyethylene-glycol-methacrylate-grafted Poly(methyl methacrylate)." International Journal of Molecular Sciences 19, no. 9 (September 14, 2018): 2764. http://dx.doi.org/10.3390/ijms19092764.
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Although poly(2-hydroxyethyl methacrylate) (pHEMA) and polyethylene glycol methacrylate (PEGMA) have been demonstrated to inhibit bacterial adhesion, no study has compared antibacterial adhesion when salivary pellicle is coated on polymethyl methacrylate (PMMA) grafted with pHEMA and on PMMA grafted with PEGMA. In this study, PMMA discs were fabricated from a commercial orthodontic acrylic resin system (Ortho-Jet). Attenuated total reflection-Fourier transform infrared spectra taken before and after grafting confirmed that pHEMA and PEGMA were successfully grafted on PMMA. Contact angle measurements revealed PMMA-pHEMA to be the most hydrophilic, followed by PMMA-PEGMA, and then by PMMA. Zeta potential analysis revealed the most negative surface charges on PMMA-PEGMA, followed by PMMA-pHEMA, and then by PMMA. Confocal laser scanning microscopy showed green fluorescence in the background, indicating images that influenced the accuracy of the quantification of live bacteria. Both the optical density value measured at 600 nm and single plate-serial dilution spotting showed that pHEMA was more effective than PEGMA against Escherichia coli and Streptococcus mutans, although the difference was not significant. Therefore, the grafting of pHEMA and PEGMA separately on PMMA is effective against bacterial adhesion, even after the grafted PMMA were coated with salivary pellicle. Surface hydrophilicity, bactericidality, and Coulomb repulsion between the negatively charged bacteria and the grafted surface contributed to the effectiveness.
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Hayashi, Y. "High-Resolution Electron Microscopy of Mineral Deposits on a Thin Layer of Pellicle Adhering to Intact Enamel Surface." Journal of Electron Microscopy 45, no. 6 (December 1, 1996): 501–4. http://dx.doi.org/10.1093/oxfordjournals.jmicro.a023475.
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Wiegand, Annette, Salome Bliggenstorfer, Ana Carolina Magalhães, Beatrice Sener, and Thomas Attin. "Impact of thein situformed salivary pellicle on enamel and dentine erosion induced by different acids." Acta Odontologica Scandinavica 66, no. 4 (January 2008): 225–30. http://dx.doi.org/10.1080/00016350802183401.
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Suryanto, Heru, Muhamad Muhajir, Neena Zakia, Uun Yanuhar, Aminnudin Aminnudin, and Yanuar Rohmat Aji Pradana. "Effect of Drying Methods on the Structure of Bacterial Cellulose from Pineapple Peel Extract." Key Engineering Materials 851 (July 2020): 79–85. http://dx.doi.org/10.4028/www.scientific.net/kem.851.79.
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Properties of Bacterial Cellulose was depended on the fermentation conditions to produce BC as well as the processing steps for modifying the Bacterial Cellulose microstructure. This study reports on the comparison effect of drying method on Bacterial Cellulose films structure produced from Pineapple Peel Extract. The drying method was done in the oven and freeze-drying. Pellicle as results of fermentation by bacteria was dried in the oven. High-pressure homogenization was applied before the freeze-drying method. BC film structure was observed using scanning electron microscopy and evaluated using X-ray diffraction. The results show that the peak of diffractogram shows crystalline peaks in a relatively similar position, which are at about 14° and 22°. High-pressure homogenizer process before freeze-drying results the structure with higher crystalline compare than oven drying. The index of crystalline and degree of crystalline of BC film in the freeze-drying method were higher than those in the oven with a value of 83% and 86% compared than 81% and 84%, respectively. Drying methods to pellicle in the oven and freeze-drying results in the degree of crystalline of 79% and 71%, respectively. The morphology of the freeze-drying methods contains a more porous structure.
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Kalmokoff, Martin, Patricia Lanthier, Tammy-Lynn Tremblay, Mary Foss, Peter C. Lau, Greg Sanders, John Austin, John Kelly, and Christine M. Szymanski. "Proteomic Analysis of Campylobacter jejuni 11168 Biofilms Reveals a Role for the Motility Complex in Biofilm Formation." Journal of Bacteriology 188, no. 12 (June 15, 2006): 4312–20. http://dx.doi.org/10.1128/jb.01975-05.
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ABSTRACT Campylobacter jejuni remains the leading cause of bacterial gastroenteritis in developed countries, and yet little is known concerning the mechanisms by which this fastidious organism survives within its environment. We have demonstrated that C. jejuni 11168 can form biofilms on a variety of surfaces. Proteomic analyses of planktonic and biofilm-grown cells demonstrated differences in protein expression profiles between the two growth modes. Proteins involved in the motility complex, including the flagellins (FlaA, FlaB), the filament cap (FliD), the basal body (FlgG, FlgG2), and the chemotactic protein (CheA), all exhibited higher levels of expression in biofilms than found in stationary-phase planktonic cells. Additional proteins with enhanced expression included those involved in the general (GroEL, GroES) and oxidative (Tpx, Ahp) stress responses, two known adhesins (Peb1, FlaC), and proteins involved in biosynthesis, energy generation, and catabolic functions. An aflagellate flhA mutant not only lost the ability to attach to a solid matrix and form a biofilm but could no longer form a pellicle at the air-liquid interface of a liquid culture. Insertional inactivation of genes that affect the flagellar filament (fliA, flaA, flaB, flaG) or the expression of the cell adhesin (flaC) also resulted in a delay in pellicle formation. These findings demonstrate that the flagellar motility complex plays a crucial role in the initial attachment of C. jejuni 11168 to solid surfaces during biofilm formation as well as in the cell-to-cell interactions required for pellicle formation. Continued expression of the motility complex in mature biofilms is unusual and suggests a role for the flagellar apparatus in the biofilm phenotype.
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Qi, H. N., Q. L. Ma, Y. R. Xie, Y. Song, J. Tian, W. S. Yu, X. T. Dong, D. Li, G. X. Liu, and J. X. Wang. "2D double aeolotropic conductive Janus pellicle with multi-functionality then derived 3D dual-wall Janus-type tube." Express Polymer Letters 14, no. 2 (2020): 154–68. http://dx.doi.org/10.3144/expresspolymlett.2020.13.
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Grychtol, Susann, Sabine Basche, Matthias Hannig, and Christian Hannig. "Effect of CPP/ACP on Initial Bioadhesion to Enamel and DentinIn Situ." Scientific World Journal 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/512682.
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The presentin situstudy investigated the influence of a preparation containing CPP/ACP (caseinphosphopeptide-amorphous calcium phosphate) (GC Tooth mousse) on initial bacterial colonization of enamel and dentin. Therefore, pellicle formation was performedin situon bovine enamel and dentin specimens fixed to individual upper jaw splints worn by 8 subjects. After 1 min of pellicle formation GC Tooth mousse was used according to manufacturer’s recommendations. Rinses with chlorhexidine served as positive controls. Specimens carried without any rinse served as negative controls. After 8 h overnight exposure of the splints, bacterial colonization was quantified by fluorescence microscopy (DAPI and BacLight live/dead staining). Additionally, the colony forming units (CFU) were determined after desorption. Furthermore, the effects onStreptococcus mutansbacteria were testedin vitro(BacLight). There was no significant impact of CPP/ACP on initial bacterial colonization proved with DAPI and BacLight. Determination of CFU showed statistical significance for CPP/ACP to reduce bacterial adherence on enamel. Thein vitroinvestigation indicated no antimicrobial effects for CPP/ACP onStreptococcus mutanssuspension. Under the chosen conditions, CPP/ACP (GC Tooth mousse) had no significant impact on initial biofilm formation on dental hard tissues. The tested preparation cannot be recommended for biofilm management.
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LEHNER, ANGELIKA, KATHRIN RIEDEL, LEO EBERL, PIETER BREEUWER, BENJAMIN DIEP, and ROGER STEPHAN. "Biofilm Formation, Extracellular Polysaccharide Production, and Cell-to-Cell Signaling in Various Enterobacter sakazakii Strains: Aspects Promoting Environmental Persistence." Journal of Food Protection 68, no. 11 (November 1, 2005): 2287–94. http://dx.doi.org/10.4315/0362-028x-68.11.2287.
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Enterobacter sakazakii is considered an opportunistic pathogen and has been implicated in food-associated cases of meningitis or enteritis, especially in neonates and infants. The organism has been detected in various types of food and in food production units, but so far only powdered infant formula has been linked to outbreaks of disease. Survival and persistence in such environments requires the ability to adapt to high osmotic potentials and/or dry conditions. Fifty-six E. sakazakii strains were evaluated for several features important for persistence and survival: (i) biofilm formation and the putative production of cellulose as one of the components of the extracellular matrix, (ii) adherence to hydrophilic and hydrophobic surfaces, (iii) the production of extracellular polysaccharides, and (iv) the ability of E. sakazakii to produce cell-to-cell signaling molecules. Pellicle and flock formation was observed in 21 of the strains grown in Luria-Bertani broth and in 44 of the strains grown in brain heart infusion broth. Calcofluor-stained fibrils, observed microscopically in every (fragile or rigid) pellicle, suggested the presence of cellulose as an extracellular compound in this type of biofilm. Twelve isolates did not form any pellicle or flocks under either condition. Twenty-three of the isolates exhibited the potential to adhere to glass surfaces in shaken cultures, and 33 strains showed biofilm formation at the air-solid interface of polyvinyl chloride microtiter wells. Sixteen isolates adhered to both surfaces. Twenty-four of the isolates tested produced a milky, viscous mass, considered as extracellular polysaccharide. High-performance liquid chromatography analysis of the polysaccharide revealed the presence of glucose, galactose, fucose, and glucuronic acid. Thin-layer chromatography analyses performed on ethyl acetate extracts of cell-free supernatants of the 56 strains indicated the presence of two different types of acylated homoserine lactones (3-oxo-C6-HSL and 3-oxo-C8-HSL). These findings illustrate the ability of E. sakazakii to produce cell-to-cell signaling molecules.
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Harder, D. E., J. Chong, R. Rohringer, and W. K. Kim. "Structure and cytochemistry of the walls of urediospores, germ tubes, and appressoria of Puccinia graminis tritici." Canadian Journal of Botany 64, no. 3 (March 1, 1986): 476–85. http://dx.doi.org/10.1139/b86-062.
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Several cytochemical methods demonstrated that urediospore walls of Puccinia graminis f. sp. tritici were probably composed of five layers, including the pellicle as the outermost layer. Two previously undescribed layers were located around the inner periphery of the spore walls. Staining for periodate-sensitive glycosubstances occurred uniformly and heavily throughout the wall except that the pellicle was unstained, and the innermost layer (3c) was more lightly stained by periodic acid – thiocarbohydrazide – silver proteinate. There was little wheat germ lectin or concanavalin A binding to the urediospore wall except in the hilar region, where wheat germ lectin bound heavily, and in the germ pore region, where binding of concanavalin A occurred. The walls of about one-half of the urediospores that were examined contained silicon deposits. Germ tube walls were composed of two layers: a broad outer layer and a narrower inner layer. The inner layer stained more heavily for periodate-sensitive glycosubstances than did the outer layer. Germ tube walls bound wheat germ lectin, but not concanavalin A. Appressorial walls were also composed of two layers, but the inner layer was much broader than that of germ tube walls, and the outer layer stained more heavily for periodate-sensitive glycosubstances. There was strong wheat germ lectin binding to the appressorial walls, but concanavalin A binding was sparse. Both germ tubes and appressoria were coated with a mucilagenouslike substance.
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Zou, Chen, Dan Qu, Haijing Jiang, Di Lu, Xiaoting Ma, Ziyi Zhao, and Yan Xu. "Bacterial Cellulose: A Versatile Chiral Host for Circularly Polarized Luminescence." Molecules 24, no. 6 (March 13, 2019): 1008. http://dx.doi.org/10.3390/molecules24061008.
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Materials capable of circularly polarized luminescence (CPL) have attracted considerable attention for their promising potential applications. Bacterial cellulose (BC) was characterized as having a stable right-handed twist, which makes it a potential chiral host to endow luminophores with CPL. Then, the CPL-active BC composite film was constructed by simply impregnating bacterial cellulose pellicles with dilute aqueous solutions of luminophores (rhodamine B, carbon dots, polymer dots) and drying under ambient conditions. Simple encapsulation of luminophores renders BC with circularly polarized luminescence with a dissymmetry factor of up to 0.03. The multiple chiral centers of bacterial cellulose provide a primary asymmetric environment that can be further modulated by supramolecular chemistry, which is responsible for its circular polarization ability. We further demonstrate that commercial grade paper may endow luminophores with CPL activity, which reifies the universality of the method.
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Vecbiskena, Linda, and Linda Rozenberga. "Nanocelluloses obtained by ammonium persulfate (APS) oxidation of bleached kraft pulp (BKP) and bacterial cellulose (BC) and their application in biocomposite films together with chitosan." Holzforschung 71, no. 7-8 (July 26, 2017): 659–66. http://dx.doi.org/10.1515/hf-2016-0187.
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AbstractBleached birch kraft pulp (BKP, Södra Cell AB, Sweden) and unmodified bacterial cellulose (BC) pellicles, biosynthesized by the bacteriumKomagataeibacter rhaeticus, were converted to cellulose nanofibersviaammonium persulfate (APS) oxidation. Fiber dimensions were investigated in an atomic force microscope, and the crystallite size was calculated by Rietveld analysis. Saos-2 osteosarcoma cell line served to assess thein vitrocytocompatibility of the biocomposite films. Results showed that individual cellulose nanofibers with an average width of 80±15 nm and a length between 600 and 1200 nm are formed by APS oxidation. The obtained BC nanofibers can be promising constituents in nanocellulose films and in chitosan-matrix films with improved physical-mechanical and biological properties. Good cellular biocompatibility was found for chitosan/oxidized cellulose films; the viability of Saos-2 osteosarcoma cells was higher on chitosan/oxidized BC films compared to chitosan/oxidized BKP films.