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111.
Shymaa Enany Yutaka Yoshida Sameh Magdeldin Xu Bo Ying Zhang Mohamed Enany Tadashi Yamamoto 《Microbiological research》2013,168(8):504-511
Two-dimensional electrophoresis (2DE) combined with mass spectrometry was used to characterize the exo-proteome secreted by two strains (ER13 and ER21) representing community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) belonging to clonal complex 80 (CC80). Common spots were detected between the 2 gels using the Progenesis SameSpots software. Two hundred and fifty-one and 312 spots from the exo-proteome of ER13 and ER21 were resolved, respectively. 2DE overlap comparison showed that 59 spots were shared. LC–MS/MS analysis identified 57 proteins from these spots comprising about 21% extracellular, 48% cytoplasmic, 2% cytoplasmic membrane, 2% cell wall, and 26% with unknown localization. The identified proteins were classified with respect to their Gene Ontology (GO) annotation as ~24% virulence determinants and toxins, ~17% involved in carbohydrate metabolism, ~14% involved in environmental stress, and ~12% associated with cell division. The identification of the enterotoxin B from the exo-products of both strains used in our study, as belonging to CC80 was interesting. 相似文献
112.
Motoo Shibata Masaru Uyeda Yutaka Kido Keiko Shigemori Yoko Aziki Toyoki Hirakawa 《Bioscience, biotechnology, and biochemistry》2013,77(9):1767-1771
From the results of taxonomic studies, Streptomyces sp. strain No. KT–151 isolated from a soil sample collected in Kumamoto City, was identified as a strain belonging to Streptomyces luteogriseus Schmitz, Deak, Crook and Hooper 1964. A new antibiotic, produced by this strain, was isolated as a leaflet crystal by ion-exchange chromatography and found to be an amino acid with the molecular formula, C5H12N2O2, and named antibiotic KT–151 (refered to as KT–151 hereinafter). The antibiotic showed antimicrobial activity against various Gram-positive and Gram-negative bacteria in a chemically defined medium but it was antagonized by several amino acids such as valine, leucine, isoleucine and threonine. 相似文献
113.
Susumu Ikegami Yutaka Hirose Yuji Kamiya Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(13):2453-2457
Partial acid hydrolysis of asterosaponin A, a steroidal saponin, afforded two new disaccharides in addition to O-(6-deoxy-α-d-glucopyranosyl)-(l→4)-6-deoxy-d-glucose which has been characterized in the preceding paper. The formers were demonstrated as O-(6-deoxy-α-d-galactopyranosyl)-(1→4)-6-deoxy-d-glucose and O-(6-deoxy-α-d-galactopyranosyl)-(l→4)-6-deoxy-d-galactose, respectively.Accordingly, the structure of carbohydrate moiety being composed of two moles each of 6-deoxy-d-galactose and 6-deoxy-d-glucose, was established as O-(6-deoxy-α-d-galactopyranosyl)-(l→4)-O-(6-deoxy-α-d-galactopyranosyl)-(l→4)-O-(6-deoxy-α-d-glucopyranosyl)-(l→4)-6-deoxy-d-glucose, which is attached to the steroidal aglycone through an O-acetal glycosidic linkage. 相似文献
114.
Koichi Hayashi Yutaka Fujii Ryuichi Saito Hiroyuki Kanao Tetsuo Hino 《Bioscience, biotechnology, and biochemistry》2013,77(12):1221-1237
The effects of solute and hydrochloric acid concentrations on optical rotation were studied using 20 naturally occuring amino acids.There appeared to be no common factor among the amino acids as far as the inclination of optical rotation was concerned. Lutz-Jirgenson’s rule could be applied to few amino acids in the cationic form. Therefore, in the determination of the optical rotation, the concentration of the solute, nature of solvent and temperature must be rigorously controlled. The optical conditions of measurement and the specific rotation of 20 amino acids were recommended based on this work. 相似文献
115.
Etsuro Sugimoto Masaaki Yoshikawa Yutaka Nishida Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(12):2497-2504
It was indicated from fluorescence spectra and fluorescence titration that a hydrophobic probe, 1-anilino-8-naphthalenesulfonate (ANS), binds to casein components (αs-, β- and κ-caseins). Fluorescence intensity and affinity of ANS-κ-casein complex were larger than that of ANS-αs- and ANS-β-casein complexes. Enhancements of fluorescence intensity of complexes of casein components were observed by the addition of KCI or CaCl2. Reason for the enhancement was postulated to be the increase of the quantum yield of the ANS fluorescence caused by the environmental change of ANS binding region of the casein components.Marked increase of sedimentation coefficient of β-casein in the presence of KCl or CaCl2 at 10°C was caused by the addition of ANS. This may be responsible for the stimulation of the Ca-dependent precipitation of β-casein by the addition of ANS.It was found that αs · κ-association was prevented by ANS and that hydrophobic interaction have an important role for αs · κ-association. 相似文献
116.
Musashi Saigusa Mizuho Nishizawa Yutaka Shimizu 《Bioscience, biotechnology, and biochemistry》2013,77(9):1518-1527
Salmon myofibrillar protein (Mf) was investigated as a source of edible anti-inflammatory products. Peptides produced by stepwise digestion of Mf (without carbohydrate) with pepsin and trypsin had little effect on the secretion of inflammation-related compounds from lipopolysaccharide-stimulated RAW 264.7 macrophage cells. However, peptides prepared from Mf conjugated with alginate oligosaccharide (AO; 19 μg/mg protein) (dMSA) through the Maillard reaction in the presence of sorbitol significantly reduced the secretion of the pro-inflammatory mediators nitric oxide, tumor necrosis factor (TNF)-α and interleukin (IL)-6, as well as mRNA expression of TNF-α, IL-6, inducible nitric oxide synthase and cyclooxygenase-2. Additionally, dMSA inhibited acute inflammation in a carrageenan-induced model of paw edema in mice, but had no effect on natural killer cell cytotoxic activity or macrophage phagocytosis. These results suggest that fish Mf conjugated with AO may be a potential food material with anti-inflammatory function. 相似文献
117.
Motoo MotooShibata Masaru Uyeda Yutaka Kido Yuki Fujimoto Yuji Takano Yukie Yoshioka 《Bioscience, biotechnology, and biochemistry》2013,77(12):3377-3382
Streptomyces sp. No. B-1625, which was identified as a strain of Streptomyces antibioticus, is a typical producer of actinomycin, but also produces minor acidic antibiotic components (FA), besides actinomycins X2, D and X0β. The FA-components, which were obtained with a high-producing mutant, 11M-21, showed antibacterial and antitumor activities, and also similar visible and UV absorption spectra to those characteristic of actinomycin. The FA-components were separated into five components, FA1 FA2α, FA2β, FA3α and FA3β, on TLC. Among them, one component, FA3β, isolated in a purified state as an orange powder, has a composition of C, 52.97: H, 6.34: N, 10.48%, and is active against B. subtilis at a MIC of 5mcg/ml. The FA3β component showed pKa′ of 5.4 and 12.0 and λmax at 443, 427 and 233 nm. From these properties, FA3β is considered to be an acidic actinomycin congener. 相似文献
118.
Yutaka Teranishi Susumu Kawamoto Atsuo Tanaka Masako Osumi Saburo Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(6):1221-1225
The catalase activity of Candida tropicalis pK 233 was induced by hydrocarbons but not by glucose, galactose, ethanol, acetate or lauryl alcohol.
The induction of the catalase activity depending upon hydrocarbons was sensitive to cycloheximide but not to chloramphenicol.
Glucose repressed strongly the induction of the catalase activity by hydrocarbons but galactose did not affect seriously.
When C. tropicalis was incubated with hydrocarbons, the appearance of microbodies was observed electronmicroscopicaliy.
119.
120.
Hirokazu Toju Akifumi S Tanabe Yutaka Notsu Teiji Sota Takema Fukatsu 《The ISME journal》2013,7(7):1378-1390
The processes and mechanisms underlying the diversification of host–microbe endosymbiotic associations are of evolutionary interest. Here we investigated the bacteriocyte-associated primary symbionts of weevils wherein the ancient symbiont Nardonella has experienced two independent replacement events: once by Curculioniphilus symbiont in the lineage of Curculio and allied weevils of the tribe Curculionini, and once by Sodalis-allied symbiont in the lineage of grain weevils of the genus Sitophilus. The Curculioniphilus symbiont was detected from 27 of 36 Curculionini species examined, the symbiont phylogeny was congruent with the host weevil phylogeny, and the symbiont gene sequences exhibited AT-biased nucleotide compositions and accelerated molecular evolution. These results suggest that the Curculioniphilus symbiont was acquired by an ancestor of the tribe Curculionini, replaced the original symbiont Nardonella, and has co-speciated with the host weevils over evolutionary time, but has been occasionally lost in several host lineages. By contrast, the Sodalis-allied symbiont of Sitophilus weevils exhibited no host–symbiont co-speciation, no AT-biased nucleotide compositions and only moderately accelerated molecular evolution. These results suggest that the Sodalis-allied symbiont was certainly acquired by an ancestor of the Sitophilus weevils and replaced the original Nardonella symbiont, but the symbiotic association must have experienced occasional re-associations such as new acquisitions, horizontal transfers, replacements and/or losses. We detected Sodalis-allied facultative symbionts in populations of the Curculionini weevils, which might represent potential evolutionary sources of the Sodalis-allied primary symbionts. Comparison of these newcomer bacteriocyte-associated symbiont lineages highlights potential evolutionary trajectories and consequences of novel symbionts after independent replacements of the same ancient symbiont. 相似文献