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141.
Naomichi Nishio Kenji Sakai Koji Fujii Tadashi Kamikubo 《Bioscience, biotechnology, and biochemistry》2013,77(3):553-559
The accumulation of vitamin B6 by Pichia guilliermondii Wickerham NK–2 strain grown on hydrocarbon was investigated. Ammonium acetate was more effective than other nitrogen sources tested. Satisfactory utilization by the yeast strain was observed in n-alkanes of C10–C18, and n-pentadecane was the best for vitamin B6 production. Vitamin B6 was excreted in the cultural broth mainly in the form of pyridoxal, The maximal vitamin B6 production was approximately 25 mg per liter of the culture broth. 相似文献
142.
143.
Yoshimoto Tadashi Nakanishi Toshihiro Fukumoto Juichiro Tsuru Daisuke 《Bioscience, biotechnology, and biochemistry》2013,77(11):1775-1782
About 100 soil samples were subjected to screening for microorganisms which were capable of producing lytic enzyme toward Staphylococcus aureus. A strain belonging to Streptomyces was isolated and found to produce lytic enzyme(s) noninduciblly, when grown aerobically at 37°C for 25 hr in a medium containing 7.5% soybean cake extract, 2% dextrin, 0.6% K2HPO4, 0.02% each of MgSO4·7H2O and KCl, pH 7.0. The crude enzyme preparation was active at pH values of 8.5 and 5.8 toward S. aureus, B. subtilis, L. bulgaricus and Str. faecalis but was completely inert against M. lysodeikticus, indicating the enzyme(s) to be distinguished from other bacteriolytic enzymes of Streptomyces so far reported. 相似文献
144.
An arylamidase was purified from Flavobacterium meningosepticum by a series of chromatographies on CM-cellulose, DEAE-Sephadex A-50 and Sephadex G-150. The purified enzyme appeared homogeneous on SDS-gel electrophoresis. The molecular weight of the enzyme was estimated to be more than 500,000 dalton by using a column of Sepharose 4B and to be 62,000 when checked by SDS-gel electrophoresis. The enzyme was most active at pH 7.5 toward Leu-β-naphthylamide (Leu-β-NA). It catalyzed the hydrolysis of not only various amino acid-β-naphthylamides but also some peptides, but the hydrolysis rate of the latter substrates was quite low. Cys-di-β-naphthylamide was split by this enzyme at an optimal pH of 6.2. Incubation of oxytocin with the enzyme resulted in a decrease in the biological activity, indicating that this arylamidase possesses an oxytocinase (cystyl aminopeptidase)-like activity. 相似文献
145.
Tadashi Inoue Masamichi Takagi Yasukiyo Umemura Hikoyuki Yamaguchi 《Bioscience, biotechnology, and biochemistry》2013,77(12):2457-2464
The minor RNA components in large ribosomal subunits of rat liver were analyzed by gel electrophoresis. Quantitative analysis showed that these minor components, whose apparent molecular weights ranged from 8.48 × 105 to 11.4 × 105, represented 10 to 13% of the total high-molecular-weight ribosomal RNA.It was elucidated that they were not artifacts arose during the cell homogenization, sub-cellular fractionation, RNA preparation and gel electrophoresis.Labeling experiment in vivo showed that they were preferentially present in “old” ribosomes. It was predicted that these minor components were the intermediates in the degradation of 28S ribosomal RNA in vivo.In the regenerating liver, where the degradation of proteins was reported to be blocked, the relative amount of the minor RNA components was decreased to about a half of that of normal liver. There was, however, no increase in their relative amount in the long-term starved rat liver, where RNA degradation should be going very rapidly. 相似文献
146.
Kanae Yokogawa Shigeo Kawata Tadashi Takemura Yoshio Yoshimura 《Bioscience, biotechnology, and biochemistry》2013,77(8):1533-1543
Two lytic enzymes capable of lysing Streptococcus mutans have been purified to give a single band on disc-gel electrophoresis, respectively. The M–1 and M–2 enzymes were both proved to be N-acetylmuramidases. However, these enzymes were entirely different on their enzymatic properties. The molecular weights were about 20,000 and 11,000 for M–1 and M–2 enzymes, respectively, The maximal lytic activity of M–1 enzyme was obtained at ionic strength 0.05, while lytic activity of M–2 enzyme did not change within the ionic strength range of 0 to 0.05. The M–1 enzyme constituted the majority of the total lytic activity against the cell walls of Streptococcus mutans BHT of cultured filtrate. The M–2 enzyme showed less specific lytic activity on the cell walls of Streptococcus mutans BHT than M–1 enzyme. 相似文献
147.
Tadashi Sudo Hideo Nagayama Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(7):1651-1659
Occurrence of cellulase activity was demonstrated in the filtrates of germinating conidiospores and growing mycelia of P. oryzae. Activity and some properties of cellulase in the filtrate of mycelia grown on rice plant powder as carbon source were compared among various strains.Cellulase activity (C1 and Cx enzymes; cellulose and carboxymethylcellulose as substrates, respectively) in the filtrate of germinating conidiospores was detected in the pathogenic T–l (Ken 53–33) strain as well as nonpathogenic 0 (THU 3 × 1) strain of P. oryzae. The activity was higher in the former than the latter strains. Cellulase activity (Cx enzyme) in the filtrate of growing mycelia was detected in the four strains used, T–l (Ken 53–33), C–3 (N 87), N–1 (H373), and 0 (THU 3 × 1). Cellulase activity (Cx enzyme) in the filtrate of mycelia was optimal at pH 5.0 and 40°C, and stable up to 40°C. Their properties did not differ significantly except for the pH-activity curve at alkaline side among various strains; but cellulase activity (C1 enzyme) was found to be correlated with their pathogenicity except for the case of C–3 strain. 相似文献
148.
Tadashi Mori Masafumi Hidaka Hiroko Ikuji Ibuki Yoshizawa Haruhiko Toyohara Toru Okuda 《Bioscience, biotechnology, and biochemistry》2013,77(5):832-838
The peptidyl prolyl cis/trans isomerase Pin1 enhances the uptake of triglycerides and the differentiation of fibroblasts into adipose cells in response to insulin stimulation. Pin1 downregulation could be a potential approach to prevent and treat obesity-related disorders. In order to identify an inhibitor of Pin1 that exhibited minimal cytotoxicity, we established a high-throughput screen for Pin1 inhibitors and used this method to identify an inhibitor from 1,056 crude fractions of two natural product libraries. The candidate, a phlorotannin called 974-B, was isolated from the seaweed, Ecklonia kurome. 974-B inhibited the differentiation of mouse embryonic fibroblasts and 3T3-L1 cells into adipose cells without inducing cytotoxicity. We discovered the Pin1 inhibitor, 974-B, from the seaweed, E. kurome, and showed that it blocks the differentiation of fibroblasts into adipose cells, suggesting that 974-B could be a lead drug candidate for obesity-related disorders. 相似文献
149.
Protein synthesis in mitochondrial and supernatant fractions of sweet potato root tissue was found to be activated up to about 3 and 1.5 times in response to wounding, respectively. The activation seemed to take place within 8 hr after slicing. Sucrose density gradient centrifugation of mitochondrial fraction prepared from the aged sliced tissue showed the presence of new fraction of mitochondrial particles which were not seen in the case of fresh tissue. The particles in the fraction were labeled by radioactive leucine in vivo more rapidly than the other particles. Chloramphenicol treatment of tissue before aging blocked the development of these particles. These results suggest that the particles were newly formed during aging. 相似文献
150.