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171.
Abstract The cell wall of Candida albicans contains mannoproteins that are covalently associated with β-1,6-glucan. When spheroplasts were allowed to regenerate a new cell wall, initially non-glucosylated cell wall proteins accumulated in the medium. While the spheroplasts became osmotically stable, β-1,6-glucosylated proteins could be identified in their cell wall by SDS-extraction or β-1,3-glucanase digestion. At later stages of regeneration, β-1,3-glucosylated proteins were also found. Hence, incorporation of proteins into the cell wall is accompanied by extracellular coupling to β-1,6-/β-l,3-glucan. The SDS-extractable glucosylated proteins probably represent degradation products of wall proteins rather than their precursors. Tunicamycin delayed, but did not prevent the formation of β-1,6-glucosylated proteins, demonstrating that β-1,6-glucan is not attached to N -glycosidic side-chains of wall proteins. 相似文献
172.
Satoru Masuda Shigefumi Kuwahara Toshio Suguro Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(11):2515-2520
The (S)-enantiomer of the sex pheromone of the yellow scale (Aonidiella citrina), (S,E)-6-isopropyl-3,9-dimethyl-5,8-decadienyl acetate, was stereoselectively synthesized from (R)-(+)-citronellic acid. 相似文献
173.
Abstract Murine monoclonal antibodies (mAbs) were selected against a cell wall glycoprotein of Saccharomyces cerevisiae . One of the mAbs (92-276/018) specifically identified S. cerevisiae and the sibling species S. paradoxus, S. pastorianus and S. bayanus in immunofluorescence studies and immunoblot analyses, while no other yeast genera except Saccharomyces were recognized. Further analysis indicated that the mAb 92-276/018 reacts with an epitope in the carbohydrate chain of the cell wall glycoproteins. 相似文献
174.
John H. Pazur Michael E. Tay Beverly A. Pazur Frank J. Miskiel 《Journal of Protein Chemistry》1987,6(5):387-399
Sets of isomeric anti-lactose antibodies with specificity for the lactose units of a cell wall polysaccharide fromStreptococcus faecalis strain N were induced in rabbits immunized with a vaccine of nonviable cells of the organism. Such sets of anti-lactose antibodies
were isolated from the serum of immunized animals by affinity chromatography on lactosyl-Sepharose. Gel electrofocusing experiments
showed that the preparations consisted of multiprotein components. One preparation of antibodies of 13 isomers was separated
into homogeneous components by liquid isoelectrofocusing. The individual isomeric antibodies exhibit specificity for the lactose
units of the antigenic polysaccharide, possess isoelectric points in the range of 5.9–8.0, and belong to the IgG class of
immunoglobulins, and each member yields one light chain and one heavy chain on dissociation in sodium dodecyl sulfate (SDS)
and mercaptoethanol. These results have been interpreted as evidence for the assembly of the chains of isomeric antibodies
by a single-chain pairing mechanism. 相似文献
175.
P. Biely 《Archives of microbiology》1978,119(2):213-214
Reevaluation and comparison of seemingly contradictory literature data on the mode of synthesis of wall polysaccharides during the cell cycle ofSaccharomyces cerevisiae explained the source of discrepancies and demonstrated their general consonance in the following points: 1. The rate of synthesis of glucan and mannan is not constant and does not increase continuously throughout the entire cell cycle. 2. The rate of synthesis of both polysaccharides is considerably reduced at the time of cell division and in the prebudding phase. 相似文献
176.
177.
Abstract Both the two major structural cell wall glycoproteins and the soluble excreted glycoproteins of Chlamydomonas reinhardii Levine WT II/32 contain low levels (approx. 1–4%) of sugar O-sulphate esters, asymmetrically distributed within the molecules. Preliminary characterization of their structure is described through [35S] sulphate labelling experiments. The function of the sulphated glycoproteins is discussed in terms of their structural role and their water retaining properties. 相似文献
178.
179.
呼吸道感染是常见的儿科疾病,有着显著的发病率和死亡率,反复呼吸道感染会严重影响儿童的生活质量和身体健康。维生素D具有一系列与人体健康有关的作用,包括与呼吸道的感染有关。为了分析维生素D与儿童反复呼吸道感染的关系,探讨维生素D影响呼吸道感染的机制,本研究通过临床分析了维生素D缺乏与儿童反复呼吸道发生之间的相关性,通过构建炎症模型,观察了外源维生素D对人气道上皮细胞增殖分化的影响,运用ELISA检测了维生素D对人气道上皮细胞和中性粒细胞释放炎症因子(IL-1β,IL-6和TNF-α)的影响。本结果表明,维生素D缺乏与儿童反复呼吸道感染相关,并且维生素D能促进人气道上皮细胞的增殖分化,但对人气道上皮细胞和中性粒细胞炎症因子的产生无显著影响。 相似文献
180.
In this study, atmospheric and room temperature plasma and ultraviolet mutagenesis was studied for astaxanthin overproducing mutant. Phaffia rhodozyma mutant Y1 was obtained from the selection plate with 120 μmol/L diphenylamine as selection agent, and its carotenoid concentration and content were 54.38 mg/L and 5.38 mg/g, which were 19.02 % and 21.20 % higher than that of the original strain, respectively. Sugarcane bagasse hydrolysate was used for astaxanthin production by mutant Y1 at 22 °C and 220 rpm for 96 h, and the biomass and carotenoid concentration reached 12.65 g/L and 88.57 mg/L, respectively. Ultrasonication and cellulase were used to break cell wall and the parameters were optimized, achieving an astaxanthin extraction rate of 96.01 %. The present work provided a novel combined mutagenesis method for astaxanthin overproducing mutant and a green cell wall disruption process for astaxanthin extraction, which would play a solid foundation on the development of natural astaxanthin. 相似文献