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1.
S Kh Khaduev O S Zhukova Ia V Dobrynin K Soda T T Berezov 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(5):603-604
L-lysine-alpha-oxidase, a new fungal enzyme catalyzing oxidative deamination of L-lysine, exerts an inhibitory effect on DNA, RNA and protein synthesis in human cells of carcinoma ovarius (CaOv) in vitro. 相似文献
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Thermostable alanine racemase from Bacillus stearothermophilus: molecular cloning of the gene, enzyme purification, and characterization 总被引:5,自引:0,他引:5
The alanine racemase (EC 5.1.1.1) gene of a thermophilic bacterium, Bacillus stearothermophilus, was cloned and expressed in Escherichia coli C600 with vector plasmid pICR301, which was constructed from pBR322 and the L-alanine dehydrogenase gene derived from B. stearothermophilus. A coupled assay method with L-alanine dehydrogenase and tetrazolium salts was used to detect visually the alanine racemase activity in the clones. Alanine racemase overproduced in a clone carrying the plasmid pICR4, 12 kilobases of DNA, was purified from cell extracts about 340-fold to homogeneity by five steps including heat treatment. The overproduced enzyme was confirmed to originate from B. stearothermophilus by an immunochemical cross-reaction with the enzyme of B. stearothermophilus. The purified enzyme has a molecular weight of about 78 000 and consists of two identical subunits of Mr of 39 000. At the optimum temperature (50 degrees C), the enzyme has a specific activity of 1800 units/mg (Vmax, D- to L-alanine). Resolution and reconstitution experiments together with the absorption spectrum of the enzyme clearly indicate that alanine racemase of B. stearothermophilus is a pyridoxal 5'-phosphate enzyme. 相似文献
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5.
Arakawa Keita; Mizuno Katsuhiko; Kishitani Sachie; Takabe Tetsuko 《Plant & cell physiology》1992,33(7):833-840
The changes in the level of the protein for betaine aldehydedehydrogenase, which catalyzes the last step in the synthesisof glycinebetaine, were analyzed with antiserum raised againstSDS-denatured betaine aldehyde dehydrogenase from spinach. Inbarley leaves, the levels of betaine aldehyde dehydrogenaseprotein were found to be enhanced by the addition of 200 mMNaCl to the growth medium. These changes in the level of theenzyme protein corresponded to those in the activity of theenzyme, as described in our previous study (Arakawa et al. 1990).The extent of this enhancement was reduced when barley plantswere relieved from salt stress. An increase in the level ofthe protein was also induced by water stress, such as the withholdingof water or the addition of polyethylene glycol 6000. Betainealdehyde dehydrogenase protein was detected in etiolated leavesand roots, as well as in green leaves. In etiolated leaves,the level of betaine aldehyde dehydrogenase protein was notaffected by salt stress.
1 This work was supported by a grant from the Bio-Media Projectof the Japanese Ministry of Agriculture, Forestry and Fisheries(BMP92-III-l-1). 相似文献
6.
Taichiro Miyake Kosuke Soda Yasushi Itoh Yoshihiro Sakoda Hirohito Ishigaki Tomoya Nagata Hideaki Ishida Misako Nakayama Hiroichi Ozaki Hideaki Tsuchiya Ryuzo Torii Hiroshi Kida & Kazumasa Ogasawara 《Journal of medical primatology》2010,39(1):58-70
Background Highly pathogenic avian influenza virus (HPAIV) infection has a high mortality rate in humans. Secondary bacterial pneumonia with HPAIV infection has not been reported in human patients, whereas seasonal influenza viruses sometimes enhance bacterial pneumonia, resulting in substantial morbidity and mortality. Therefore, if HPAIV infection were accompanied by bacterial infection, an increase in mortality would be expected. We examined whether a vaccine against HPAIV prevents severe morbidity caused by mixed infection with HPAIV and bacteria.
Methods H7N7 subtype of HPAIV and Streptococcus pneumoniae were inoculated into cynomolgus macaques with or without vaccination of inactivated whole virus particles .
Results Vaccination against H7N7 HPAIV decreased morbidity caused by HPAIV and pneumonia caused by S. pneumoniae . Bacterial replication in lungs was decreased by vaccination against HPAIV, although the reduction in bacterial colonies was not significant.
Conclusions Vaccination against HPAIV reduces pneumonia caused by bacterial superinfection and may improve prognosis of HPAIV-infected patients. 相似文献
Methods H7N7 subtype of HPAIV and Streptococcus pneumoniae were inoculated into cynomolgus macaques with or without vaccination of inactivated whole virus particles .
Results Vaccination against H7N7 HPAIV decreased morbidity caused by HPAIV and pneumonia caused by S. pneumoniae . Bacterial replication in lungs was decreased by vaccination against HPAIV, although the reduction in bacterial colonies was not significant.
Conclusions Vaccination against HPAIV reduces pneumonia caused by bacterial superinfection and may improve prognosis of HPAIV-infected patients. 相似文献
7.
Naoki Shibata Hiroko Tamagaki Naoki Hieda Keita Akita Hirofumi Komori Yasuhito Shomura Shin-ichi Terawaki Koichi Mori Noritake Yasuoka Yoshiki Higuchi Tetsuo Toraya 《The Journal of biological chemistry》2010,285(34):26484-26493
N-terminal truncation of the Escherichia coli ethanolamine ammonia-lyase β-subunit does not affect the catalytic properties of the enzyme (Akita, K., Hieda, N., Baba, N., Kawaguchi, S., Sakamoto, H., Nakanishi, Y., Yamanishi, M., Mori, K., and Toraya, T. (2010) J. Biochem. 147, 83–93). The binary complex of the truncated enzyme with cyanocobalamin and the ternary complex with cyanocobalamin or adeninylpentylcobalamin and substrates were crystallized, and their x-ray structures were analyzed. The enzyme exists as a trimer of the (αβ)2 dimer. The active site is in the (β/α)8 barrel of the α-subunit; the β-subunit covers the lower part of the cobalamin that is bound in the interface of the α- and β-subunits. The structure complexed with adeninylpentylcobalamin revealed the presence of an adenine ring-binding pocket in the enzyme that accommodates the adenine moiety through a hydrogen bond network. The substrate is bound by six hydrogen bonds with active-site residues. Argα160 contributes to substrate binding most likely by hydrogen bonding with the O1 atom. The modeling study implies that marked angular strains and tensile forces induced by tight enzyme-coenzyme interactions are responsible for breaking the coenzyme Co–C bond. The coenzyme adenosyl radical in the productive conformation was modeled by superimposing its adenine ring on the adenine ring-binding site followed by ribosyl rotation around the N-glycosidic bond. A major structural change upon substrate binding was not observed with this particular enzyme. Gluα287, one of the substrate-binding residues, has a direct contact with the ribose group of the modeled adenosylcobalamin, which may contribute to the substrate-induced additional labilization of the Co–C bond. 相似文献
8.
Malay Choudhury Takahiro Oku Shoji Yamada Masaharu Komatsu Keita Kudoh Takao Itakura Seiichi Ando 《Central European Journal of Biology》2011,6(4):545-557
Apolipoproteins such as apolipoprotein (apo) A-I, apoA-IV, and apoE are lipid binding proteins synthesized mainly in the liver
and the intestine and play an important role in the transfer of exogenous or endogenous lipids through the circulatory system.
To investigate the mechanism of lipid transport in fish, we have isolated some novel genes of the apoA-I family, apoIA-I (apoA-I isoform) 1–11, from Japanese eel by PCR amplification. Some of the isolated genes of apoIA-I corresponded to 28kDa-1 cDNAs which had already been deposited into the database and encoded an apolipoprotein with molecular
weight of 28 kDa in the LDL, whereas others seemed to be novel genes. The structural organization of all apoIA-Is consisted of four exons separated by three introns. ApoIA-I10 had a total length of 3232 bp, whereas other genes except for apoIA-I9 ranged from 1280 to 1441 bp. The sequences of apoIA-Is at the exon-intron junctions were mostly consistent with the consensus sequence (GT/AG) at exon-intron boundaries, whereas
the sequences of 3′ splice acceptor in intron 1 of apoIA-I1-7 were (AC) but not (AG). The deduced amino acid sequences of all apoIA-Is contained a putative signal peptide and a propeptide
of 17 and 5 amino acid residues, respectively. The mature proteins of apoIA-I1-3, 7, and 8 consisted of 237 amino acids, whereas
those of apoIA-I4-6 consisted of 239 amino acids. The mature apoIA-I10 sequence showed 65% identity to amino acid sequence
of apoIA-I11 which was associated with an apolipoprotein with molecular weight of 23 kDa in the VLDL. All these mature apoIA-I
sequences satisfied the common structural features depicted for the exchangeable apolipoproteins such as apoA-I, apoA-IV,
and apoE but apoIA-I11 lacked internal repeats 7, 8, and 9 when compared with other members of apoA-I family. Phylogenetic
analysis showed that these novel apoIA-Is isolated from Japanese eel were much closer to apoA-I than apoA-IV and apoE, suggesting
new members of the apoA-I family. 相似文献
9.
Identification and characterization of a brilliant yellow pigment produced by Bordetella pertussis 下载免费PDF全文
Keita Odanaka Masato Iwatsuki Tomomitsu Satho Mineo Watanabe 《Microbiology and immunology》2017,61(11):490-496
10.
Kumagai K Barinova AA Nakajima M Taniguchi N 《Marine biotechnology (New York, N.Y.)》2004,6(3):221-228
Threeline grunt (Parapristipoma trilineatum) distributes around the southwestern coast of Japan and the east coast of China. The Chinese P. trilineatum was imported by Japan as an aquacultural seed because of its rapid growth compared with that of the Japanese P. trilineatum. The Japanese P. trilineatum differs from the Chinese P. trilineatum in some quantitative traits, and it has been suggested that these two P. trilineatum populations are genetically different. In order to identify the population structures around Japan and China, 5 local populations of the Japanese P. trilineatum and 2 local populations of the Chinese P. trilineatum were analyzed using 4 microsatellite DNA markers. Significant differences were detected between Japanese and Chinese P. trilineatum and among samples of Chinese P. trilineatum; however, among the samples of Japanese P. trilineatum, no significant differences were detected. These results suggest that care must be taken to prevent the escape of the Chinese P. trilineatum from culture cages around the Japanese coast, in order to preserve the genetically different population structures of Japanese and Chinese P. trilineatum. 相似文献