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1.
Abstract Clostridium perfringens alpha-toxin was produced in a protein-hyperproducing strain, Bacillus brevis 47, by cloning the gene into the constructed expression-secretion vector which has the multiple promoters and the signal peptide coding region of an outer cell wall protein gene. The amount of alpha-toxin produced by the B. brevis 47 transformant carrying the gene was approximately 10 times greater than that produced by a B. subtilis transformant carrying the toxin gene. Biological activities and the N-terminal amino acid sequence of the toxin secreted by the B. brevis 47 transformant were identical to those of wild-type alpha-toxin. 相似文献
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Tsutomu Yamaguchi Norihiro Tsukakoshi Gakuzo Tamura Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(4):475-480
The components of fractions obtained by dialyzing and differential centrifuging the “Ghost” of Bacillus megaterium were analyzed in detail. The compositions of amino acids in the main fractions (Fraction 2 and 3) of the “Ghosts”, were estimated. Fraction 2 was rich in non-polar amino acids, while Fraction 3 was scanty of them. Most of the fatty acids in Fraction 2 were 12-methyl tetradecanoic acid, while in Fraction 3 many kinds of fatty acid were detected.As for the localization of enzymes, the three enzymes, glucose oxidase, succinic dehydrogenase and reduced nicotinamide-adenine dinucleotide oxidase, which were present in the original “Ghosts”, were mostly observed in Fraction 2, and a very little amount of them was found in the other fractions. Further, Fraction 2 could be dissolved in formic acid and dialysis of the solution brought about reaggregation to form membrane-like structure in the presence of Ca or Mg ion. 相似文献
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Dr. Karl v. Keißler 《Plant Systematics and Evolution》1909,59(7):275-279
Ohne Zusammenfassung 相似文献
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Yoshifumi Abe Atsuhiko Matsunaga Ryota Matsuzawa Toshiki Kutsuna Shuhei Yamamoto Kei Yoneki Manae Harada Ryoma Ishikawa Takaaki Watanabe Atsushi Yoshida 《PloS one》2016,11(3)
Walking ability is significantly lower in hemodialysis patients compared to healthy people. Decreased walking ability characterized by slow walking speed is associated with adverse clinical events, but determinants of decreased walking speed in hemodialysis patients are unknown. The purpose of this study was to identify factors associated with slow walking speed in ambulatory hemodialysis patients. Subjects were 122 outpatients (64 men, 58 women; mean age, 68 years) undergoing hemodialysis. Clinical characteristics including comorbidities, motor function (strength, flexibility, and balance), and maximum walking speed (MWS) were measured and compared across sex-specific tertiles of MWS. Univariate and multivariate logistic regression analyses were performed to examine whether clinical characteristics and motor function could discriminate between the lowest, middle, and highest tertiles of MWS. Significant and common factors that discriminated the lowest and highest tertiles of MWS from other categories were presence of cardiac disease (lowest: odds ratio [OR] = 3.33, 95% confidence interval [CI] = 1.26–8.83, P<0.05; highest: OR = 2.84, 95% CI = 1.18–6.84, P<0.05), leg strength (OR = 0.62, 95% CI = 0.40–0.95, P<0.05; OR = 0.57, 95% CI = 0.39–0.82, P<0.01), and standing balance (OR = 0.76, 95% CI = 0.63–0.92, P<0.01; OR = 0.81, 95% CI = 0.68–0.97, P<0.05). History of fracture (OR = 3.35, 95% CI = 1.08–10.38; P<0.05) was a significant factor only in the lowest tertile. Cardiac disease, history of fracture, decreased leg strength, and poor standing balance were independently associated with slow walking speed in ambulatory hemodialysis patients. These findings provide useful data for planning effective therapeutic regimens to prevent decreases in walking ability in ambulatory hemodialysis patients. 相似文献
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Hui Wang Ping‐Kei Chan Si‐Yuan Pan Kwok‐Ho Kwon Yan Ye Jian‐Hong Chu Wang‐Fun Fong Wilson M.S. Tsui Zhi‐Ling Yu 《Journal of cellular biochemistry》2010,110(6):1447-1456
Pathogenesis of nonalcoholic fatty liver disease (NAFLD) is not clear. In this study we aimed to identify proteins involved in NAFLD development in free fatty acids (FFA)‐induced hepatosteatotic cells and in human liver biopsies. Steatosis was induced by incubating a normal human hepatocyte‐derived cell line L‐02 with FFA. Differentially expressed proteins in the steatotic cells were analyzed by two‐dimensional gel electrophoresis‐based proteomics. Involvement of one of the up‐regulated proteins in steatosis was characterized using the RNA interference approach with the steatotic cells. Protein expression levels in liver biopsies of patients with NAFLD were assessed by immunohistochemistry. Proteomic analysis of L‐02 steatotic cells revealed the up‐regulation of ERp57, a condition not previously implicated in NAFLD. Knockdown of ERp57 expression with siRNA significantly reduced fat accumulation in the steatotic cells. ERp57 expression was detected in 16 out of 17 patient biopsies and correlated with inflammation grades or fibrosis stages, while in 5 normal biopsies ERp57 expression was not detectable in hepatocytes. In conclusion, ERp57 was up‐regulated in FFA‐induced steatotic hepatic cells and in NAFLD patient livers and demonstrated steatotic properties in cultured cells. Further investigations are warranted to verify the involvement of ERp57 in NAFLD development. J. Cell. Biochem. 110: 1447–1456, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Kei C. Sit Derek van Lonkhuyzen Terry Walsh 《Journal of biomolecular structure & dynamics》2017,35(4):857-867
The insulin receptor (IR) plays critical roles in metabolism and growth, directed by the binding of insulin. Decades of research to understand the mechanism of insulin binding and activation of the IR have identified a region of the receptor, the C-terminal (CT) peptide, to be crucial for insulin binding. In particular, a truncated IR consisting of the first three domains fused to the CT peptide was found to bind insulin with nanomolar affinity, with undetectable binding in the absence of fused or soluble CT peptide. Problematically, all current crystal structures of the IR indicate the fusion point of the CT peptide to the three domains is located far from the position of the CT peptide as resolved in such structures. We have attempted to address this problem using molecular modelling and dynamics simulations. The results led to the identification of a potential inter-domain interaction between the L2 domain and the CT peptide that is not observed in any of the crystal structures of the IR. Investigations into this new interaction found a conformational change that could potentially be in response to insulin binding. Additionally, further simulation work with the new conformation demonstrated its compatibility with the position and orientation of insulin from the latest insulin-bound IR crystal structure. 相似文献
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Inositol deficiency of Schizosaccharomyces pombe did not induce significant change of contents of various cellular components except for phospholipids and inositol. The most remarkable decrease in inositol content by the deficiency occurred in the mitochondrial fraction. Electronmicroscopic observation of the inositol-deficient cells of Sch. pombe showed no remarkable thickening of cell wall as occurred in the inositol-exacting mutant of Saccharomyces cerevisiae Strain A–21–20.Marked loss of fermentative activity under the aerobic condition was caused from inositol deficiency without significant change of activities of respiration and anaerobic fermentation. This seemed to indicate elevated regulatory control of the fermentative activity by oxygen in the inositol-deficient Sch. pombe.Phosphorylative activities of intact cells and the isolated mitochondria coupled with oxidation was also remarkably suppressed by inositol deficiency. 相似文献
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