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81.
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.
82.
Yoshio Nakao Tsuneo Kanamaru Masakazu Kikuchi Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(10):2399-2404
The addition of penicillin to cells of Corynebacterium alkanolyticum No. 314 growing on n-paraffins medium caused the simultaneous excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid.Among many antibiotics which inhibit cell wall synthesis, only the inhibitors of peptideglycan transpeptidase such as penicillin G and cephaloridine were effective for inducing the excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid, while the others promoted only the excretion of UDP-N-acetylhexosamine derivatives.From the close relationship between the excretion of L-glutamic acid and the excretion of phospholipids, it was suggested that the action of penicillins and cephalosporins on the cell membrane resulted in the excretion of L-glutamic acid. 相似文献
83.
Toshiya Kamikado Ching-Fun Chang Shigeo Murakoshi Akira Sakurai Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(4):833-836
Two lignans were isolated from leaves of Magnolia kobus DC. as growth inhibitors on silkworm larvae and structurally elucidated as sesamin (I) and kobusin (II) which has been hitherto unknown. 相似文献
84.
Masayoshi Mishina Masakazu Isurugi Atsuo Tanaka Saburo Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(4):635-640
The content of total cellular lipid of Candida tropicalis grown on a mixture of n-alkanes (C10–C18) was about 20% of the dry cell weight at the exponential growth phase and 14% at the early stationary phase. Phospholipid corresponded to approximately 70 % of the total lipid independent of the growth phases. The composition of cellular lipid classes did not change significantly during the growth. On the other hand, a drastic time-course change in fatty acid composition was observed. The proportion of odd-chain fatty acids, one of the most specific cellular components of the yeast grown on the n-alkane mixture, increased in both phospholipid and triglyceride along with the yeast growth. In the meantime, the proportion of polyunsaturated fatty acids varied markedly during the course of cultivation, showing a peak at the early growth phase. The high content of polyunsaturated fatty acids at the early stages of growth correlated to the contents of these acids in phospholipid rather than in triglyceride. 相似文献
85.
Yasuo Kimura Nobutaka Takahashi Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1507-1516
Biosynthesis of piericidins A and B (PA and PB) has been investigated using 14C-labeled compounds. Incorporation ratios of dl-methionine(methyl-14C), propionate-1-14C and acetate-1-14C and-2-14C were 7.4, 4,5, 1.2 and 0.9%, respectively, whereas dl-mevalonic lactone- 2-14C and formate-14C were not incorporated. Degradation studies on labeled PA show that in the biosynthesis of piericidins a long branched C23-chain was formed from five propionate and four acetate units and then a nitrogen atom was introduced at the terminal part of the chain, followed by cyclization to form the pyridine ring. The two methoxyl groups on the rings of PA and PB as well as the one in the side chain of PB were derived from S-methyl of methionine. 相似文献
86.
Tetsuo Nakano Ei-Tora Yamamura Hiroshi Fujita Teruo Sone Kozo Asano 《Bioscience, biotechnology, and biochemistry》2013,77(11):1889-1901
ABSTRACTPolyinosinic-polycytidylic acid (PIC), a double-stranded RNA that induces innate immunity in mammals, is a candidate immunopotentiator for pharmaceuticals. The potency and adverse effects of PIC are strongly correlated with the nucleotide length, and the inability to precisely control the length in PIC production limits its practical use. Length extension during the annealing process is the major factor underlying the lack of control, but tuning the annealing conditions is insufficient to resolve this issue. In this study, we developed a novel method to produce accurate nucleotide length PIC at an industrial scale. The length extension was significantly suppressed by the assembly of multiple short polyinosinic acid molecules with one long polycytidylic acid molecule. A newly developed PIC, uPIC100-400, demonstrated a reproducible length and better storage stability than that of corresponding evenly structured PIC. Human dsRNA receptors exhibited equivalent responsiveness to uPIC100-400 and the evenly structured PIC with the same length. 相似文献
87.
Kunitoyo Shibuya Michio Tanaka Takeo Nanbata Kiyoshi Isono Saburo Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(7):1229-1236
Polyoxins D, E, and F which possess 5-carboxyuracil as the nucleobase were reacted selectively with sodium bisulfite at pH 4.0 resulting in facile decarboxylation to afford corresponding 5,6-dihydrouracil-6-sulfonates and uracil type polyoxins (polyoxins L, M, and K) in good yield. The former compounds were also converted to the latter almost quantitatively with mild alkali treatment. Biological activities of the transformed compounds were described. 相似文献
88.
Ryotaro Myokei Akira Sakurai Ching-Fun Chang Yoshinori Kodaira Nobutaka Takahashi Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1491-1500
A new insecticidal substance named aspochracin was isolated from the culture filtrate of Aspergillus ochraceus, a pathogenic fungus causing muscardine on insects. The compound was found to be a novel cyclotripeptide, composed of N-methyl-l-alanine, N-methyl-l-valine and l-ornithine, containing an octatrienoic acid side chain. Isolation procedure, structural elucidation and biological activities are described in detail.Hexahydroaspochracin (II) derived on hydrogenation of aspochracin (I), an insecticidal metabolite of Aspergillus ochraceus, was synthesized by cyclization of N-methyl-l-valyl-N- methyl-l-alanyl-α-caprylyl-l-ornithine (XIV). In addition to II, isohexahydroaspochracin (XV) was isolated from the reaction mixture. 相似文献
89.
Disulfide bond mediates aggregation, toxicity, and ubiquitylation of familial amyotrophic lateral sclerosis-linked mutant SOD1 总被引:5,自引:0,他引:5
Niwa J Yamada S Ishigaki S Sone J Takahashi M Katsuno M Tanaka F Doyu M Sobue G 《The Journal of biological chemistry》2007,282(38):28087-28095
Mutations in the Cu/Zn-superoxide dismutase (SOD1) gene cause familial amyotrophic lateral sclerosis (ALS) through the gain of a toxic function; however, the nature of this toxic function remains largely unknown. Ubiquitylated aggregates of mutant SOD1 proteins in affected brain lesions are pathological hallmarks of the disease and are suggested to be involved in several proposed mechanisms of motor neuron death. Recent studies suggest that mutant SOD1 readily forms an incorrect disulfide bond upon mild oxidative stress in vitro, and the insoluble SOD1 aggregates in spinal cord of ALS model mice contain multimers cross-linked via intermolecular disulfide bonds. Here we show that a non-physiological intermolecular disulfide bond between cysteines at positions 6 and 111 of mutant SOD1 is important for high molecular weight aggregate formation, ubiquitylation, and neurotoxicity, all of which were dramatically reduced when the pertinent cysteines were replaced in mutant SOD1 expressed in Neuro-2a cells. Dorfin is a ubiquityl ligase that specifically binds familial ALS-linked mutant SOD1 and ubiquitylates it, thereby promoting its degradation. We found that Dorfin ubiquitylated mutant SOD1 by recognizing the Cys(6)- and Cys(111)-disulfide cross-linked form and targeted it for proteasomal degradation. 相似文献
90.
Miyata Seiko Otake Hironao Fujishiro Hiroshige Iwamoto Kunihiro Noda Akiko Sone Michihiko Ozaki Norio 《Sleep and biological rhythms》2022,20(3):403-411
Sleep and Biological Rhythms - Sleep problems and obstructive sleep apnea (OSA) increase with age and disturb life in old age. Positional therapy is one option to treat OSA, but the differences in... 相似文献