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51.
52.
The adhesive property to the intestinal mucin of Bifidobacterium lactis LKM512, B. longum, B. breve, B. bifidum, B. adolescentis, B. infantis, Bacteroides vulgatus, Bacteroides distasonis, Eubacterium aerofaciens,
Clostridium perfringens, Escherichia coli, and Lactobacillus acidophilus were examined. Adhesive rate of LKM512 to the mucin was significantly (p < 0.05, 0.01, or 0.001) stronger than the other strains from 2 to 100 time. Though the adhesive property of many strains was
almost same to the mucin of 20-year-old and 50-year-old generations, in case of 4-month-old was different. Adhesive inhibitory
effect of C. perfringens to the mucin by LKM512 was examined. Under the condition that LKM512 was 108/ml and that C. perfringens was 106/ml, adhesion of C. perfringens to the mucin was inhibited at 99.6%, when LKM512 adhered in advance. There was the strong inhibition of adhesion at 74.0%,
when C. perfringens adhered to mucin in advance. Thus, LKM512 can inhibit the adhesion of harmful bacteria to the intestinal mucin, the possibility
of using as a probiotic strain has to be verified. 相似文献
53.
Momose Y Honda T Inagaki M Shimizu K Irie K Nakanishi H Takai Y 《Biochemical and biophysical research communications》2002,292(1):45-49
We investigated whether and how rat liver thioredoxin reductase spares alpha-tocopherol in biomembranes. Purified hydroperoxides of beta-linoleoyl-gamma-palmitoylphosphatidylcholine were decreased 35% by treatment with thioredoxin reductase and 54% by thioredoxin reductase plus E. coli thioredoxin. Thioredoxin reductase also halved the amount of hydroperoxides that had been formed during photoperoxidation of liposomes composed of beta-linoleoyl-gamma-palmitoylphosphatidylcholine, and of emulsions of both cholesterol and cholesteryl linolenate. In erythrocyte ghosts, thioredoxin reductase spared alpha-tocopherol from oxidation by both soybean lipoxygenase and ferricyanide. Thioredoxin reductase also decreased F(2)-isoprostanes in ghosts oxidized by ferricyanide, suggesting that its ability to spare alpha-tocopherol relates to reduction of lipid hydroperoxides. 相似文献
54.
Summary. We investigated the behavior of migration of Amoeba proteus in an isotropic environment. We found that the trajectory in the migration of A. proteus is smooth in the observation time of 500-1000 s, but its migration every second (the cell velocity) on the trajectory randomly changes. Stochastic analysis of the cell velocity and the turn angle of the trajectory has shown that the histograms of the both variables well fit to Gaussian curves. Supposing a simple model equation for the cell motion, we have estimated the motive force of the migrating cell, which is of the order of piconewton. Furthermore, we have found that the cell velocity and the turn angle have a negative cross-correlation coefficient, which suggests that the amoeba explores better environment by changing frequently its migrating direction at a low speed and it moves rectilinearly to the best environment at a high speed. On the other hand, the model equation has simulated the negative correlation between the cell velocity and the turn angle. This indicates that the apparently rational behavior comes from intrinsic characteristics in the dynamical system where the motive force is not torquelike. 相似文献
55.
A subunit of the mammalian oligosaccharyltransferase, DAD1, interacts with Mcl-1, one of the bcl-2 protein family 总被引:4,自引:0,他引:4
DAD1 is a mammalian homologue of Saccharomyces cerevisiae Ost2p, a subunit of the oligosaccharyltransferase complex. Loss of its function induces apoptosis in hamster BHK21 cells. By means of a two-hybrid method involving DAD1 as bait, the C-terminal region of Mcl-1, one of the bcl-2 family, was isolated. Consistently, DAD1 binds well to Mcl-1 in COS cells when overexpressed. On deletion analysis, the C-terminal domain of Mcl-1 containing BH(2) (bcl-2 homologous domain) was found to be essential for the interaction with DAD1. On the other hand, the C-terminal half of DAD1 was concluded to be essential for the interaction with Mcl-1. Surprisingly, a DeltaC-DAD1 mutant lacking only 4 amino acid residues from the C-terminus did not complement the tsBN7 mutation, while it interacted well with Mcl-1. In contrast, DeltaN-DAD1 lacking 20 amino acid residues from the N-terminus still exhibited the ability to complement the tsBN7 mutation. Thus, the C-terminus of DAD1 was suggested to play an important role in N-linked glycosylation and to complement the tsBN7 mutation. Mcl-1 may be required for the inhibition of apoptotic cell death caused by a loss of DAD1. 相似文献
56.
Yoshimi M Sekiguchi T Hara N Nishimoto T 《Biochemical and biophysical research communications》2000,276(3):965-969
The tsBN7 cell line is one of the temperature-sensitive mutants for cell proliferation derived from hamster BHK21 cell line. It has a mutation in the DAD1 gene and enters apoptosis at the restrictive temperature of 39 degrees C. The defect of Dad1p causes a loss of N-linked glycosylation; therefore, it was thought that an inhibition of N-linked glycosylation induced apoptosis.However, tunicamycin, a potent inhibitor of N-linked glycosylation, had not caused apoptosis in wild-type BHK21 cells. In order to clarify this discrepancy, wild-type BHK21 cells treated with tunicamycin and tsBN7 cells incubated at 39.5 degrees C were examined by the annexin V staining and TUNEL methods. Both methods showed that tunicamycin induces apoptosis in wild-type BHK21 cells, similar to the defect of Dad1p. Thus, we concluded that loss of N-linked glycosylation causes apoptosis. 相似文献
57.
Phenotypic Characterization of Polysaccharidases Produced by Four Prevotella Type Strains 总被引:3,自引:0,他引:3
Matsui H Ogata K Tajima K Nakamura M Nagamine T Aminov RI Benno Y 《Current microbiology》2000,41(1):45-49
Four ruminal Prevotella type strains, P. ruminicola JCM8958T, P. bryantii B14T, P. albensis M384T, and P. brevis ATCC19188T, were characterized for polysaccharide-degrading activities with the reducing sugar release assay and zymogram analyses.
Carboxymethylcellulase, xylanase, and polygalacturonate (PG)-degrading enzyme activities were determined in cultures grown
on oat spelt xylan, xylose, arabinose, cellobiose, and glucose as sole growth substrates. P. ruminicola and P. albensis showed carboxymethylcellulase induction patterns. When xylan was supplied as a sole growth substrate, xylanase activities
produced by P. bryantii and P. albensis were at least 18- and 11-fold higher, respectively, than during growth on other carbohydrates, suggesting that the regulation
of the xylanases was highly specific to xylan. All strains constitutively produced PG-degrading enzymes. The corresponding
activity of P. bryantii was more than 40-fold higher than in other strains. Zymogram analyses routinely detected the presence of high-molecular-weight
(100–170 kDa) polysaccharide-degrading enzymes in ruminal Prevotella. Characteristics of the polysaccharide-degrading activities showed diversity of ruminal Prevotella species.
Received: 29 November 1999 / Accepted: 1 February 2000 相似文献
58.
Cai Y Benno Y Takeda A Yoshida T Itaya T Nakase T 《The Journal of General and Applied Microbiology》1998,44(2):153-159
Thirty-six isolates of Leuconostoc spp. were isolated from yellow spots that occurred on the surface of vacuum-packaged ham. All isolates were Gram-positive, catalase-negative cocci that produced gas from glucose and formed more than 90% of their lactate as D(-) isomer. These isolates could grow at 4 degrees C but not above 30 degrees C and most strains produced yellow spots on the ham. The isolates were divided into three groups by sugar fermentation patterns. Representative strains from three groups showed intergroup DNA homology values of above 88.8%, showing that these groups were composed of a single species. This organism was positioned at a separate branch in the genus Leuconostoc on the phylogenetic tree based on 16S rRNA sequences, which was assigned to Leuconostoc gelidum on the basis of DNA-DNA relatedness. 相似文献
59.
Rho and Rab Small G Proteins Coordinately Reorganize Stress Fibers and Focal Adhesions in MDCK Cells 总被引:6,自引:1,他引:5 下载免费PDF全文
Hiroshi Imamura Kenji Takaishi Katsutoshi Nakano Atsuko Kodama Hideto Oishi Hitoshi Shiozaki Morito Monden Takuya Sasaki Yoshimi Takai 《Molecular biology of the cell》1998,9(9):2561-2575
The Rho subfamily of the Rho small G protein family (Rho) regulates formation of stress fibers and focal adhesions in many types of cultured cells. In moving cells, dynamic and coordinate disassembly and reassembly of stress fibers and focal adhesions are observed, but the precise mechanisms in the regulation of these processes are poorly understood. We previously showed that 12-O-tetradecanoylphorbol-13-acetate (TPA) first induced disassembly of stress fibers and focal adhesions followed by their reassembly in MDCK cells. The reassembled stress fibers showed radial-like morphology that was apparently different from the original. We analyzed here the mechanisms of these TPA-induced processes. Rho inactivation and activation were necessary for the TPA-induced disassembly and reassembly, respectively, of stress fibers and focal adhesions. Both inactivation and activation of the Rac subfamily of the Rho family (Rac) inhibited the TPA-induced reassembly of stress fibers and focal adhesions but not their TPA-induced disassembly. Moreover, microinjection or transient expression of Rab GDI, a regulator of all the Rab small G protein family members, inhibited the TPA-induced reassembly of stress fibers and focal adhesions but not their TPA-induced disassembly, indicating that, furthermore, activation of some Rab family members is necessary for their TPA-induced reassembly. Of the Rab family members, at least Rab5 activation was necessary for the TPA-induced reassembly of stress fibers and focal adhesions. The TPA-induced, small G protein-mediated reorganization of stress fibers and focal adhesions was closely related to the TPA-induced cell motility. These results indicate that the Rho and Rab family members coordinately regulate the TPA-induced reorganization of stress fibers and focal adhesions that may cause cell motility. 相似文献
60.
Takeshi Nishijima Shigeko Yashiro Katsuji Teruya Yoshimi Kikuchi Naomichi Katai Shinichi Oka Hiroyuki Gatanaga 《PloS one》2015,10(9)