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901.
Characterization of Four Amino Acids Constituting Cyl-2, a Metabolite from Cylindrocladium scoparium
Akira Hirota Akinori Suzuki Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(5):1185-1189
A biologically active metabolite designated Cyl-2 from a phytopathogenic fungus, Cylindrocladium scoparium, was found to be composed of four amino acid residues, which fully account for all of the atoms constituting Cyl-2. These amino acids were identified as L-pipecolic acid, L-isoleucine, D-O-methyltyrosine and 2-amino-8-oxo-9,10-epoxydecanoic acid. Thus, Cyl-2 was established as a cyclotetrapeptide containing novel amino acid residues. 相似文献
902.
903.
Tetsuya Yamada Hiroo Aoki Teiichi Tamura Yutaka Sakamoto 《Bioscience, biotechnology, and biochemistry》2013,77(1):85-91
A glycoside “Sasanquin” was separated from methanol extract of young leaves of Camellia sasanqua Thunb. It was not able to be found in young leaves of Camellia japonica L. and Thea sinensis L. on paper chromatogram. Investigations showed that this glycoside is composed of eugenol, D-glucose and D-xylose, and it has a structure of 3-methoxy-4-β-primeverosidoxy-allylbenzene. 相似文献
904.
Juhyun Yu Gakuzo Tamura Nobutaka Takahashi Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(7):831-836
Structure (VII), 7-methyl-13-phenyl-3-oxo-trideca-4, 6, 8, 10, 12-pentaene, was suggested for asperyellone, a yellow pigment isolated from mycelium of Aspergillus awamori 22–2–2. 相似文献
905.
Takeshi Uozumi Gakuzo Tamura Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(5):636-652
An intracellular nuclease inhibitor was 1270 times purified from a heat treated cell free extract of fresh mycelia of Aspergillus oryzae, by ammonium sulfate fractionation and chromatographies using DEAE-cellulose and Sephadex G-75. The purified sample of the inhibitor showed a UV absorption curve typical for protein, and it was inactivated by proteases such as chymotrypsin. The inhibitor stoichiometrically inactivated nuclease O (an intracellular nuclease of Asp. oryzae), forming an enzyme-inhibitor complex. But, it did not affect nuclease S1, RNase T1, RNase T2 or pancreatic RNase. The inhibitor was insensitive to 10?5m p-chloromercuribenzoate or 10?4m Pb2+. Molecular weights estimated by the method of Andrews were 23,000 for the inhibitor, 47,000 for nuclease O, and 82,000 for the enzyme-inhibitor complex. The nuclease activity was recovered from the inactive complex by the action of chymotrypsin.Nuclease O of Asp. oryzae was purified and crystallized from 113.5 kg of wet mycelia and 2 kl of culture filtrate, by salting out with ammonium sulfate and by chromatographies on CM-Sephadex C-50 and Sephadex G-100. The purified nuclease showed a single peak with apparent sedimentation constant 2.9S in an ultracentrifuge. The molecular weight measured by short column method was 64,000. The nuclease was completely inhibited by the specific nuclease inhibitor obtained from Asp. oryzae. The nuclease was activated by 0.1 mm Mg2+ and Mn2+, and completely inhibited by 1 mm EDTA. Optimum pH for activity was 7.6 for RNA and 7.4 for DNA. The nuclease degraded polyadenylic acid, polyuridylic acid and polycytidylic acid without forming detectable amount of mononucleotides. And, the main product from RNA was oligonucleotides. The enzyme showed no nonspecific phosphodiesterase activity. 相似文献
906.
Makoto Takai Satoshi Miyamoto Yoshio Hattori Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):876-877
Isolation and screening tests were carried out in order to find microorganisms which were able to produce citric acid directly from blackstrap molasses. Some strains were obtained which accumulate considerable quantities of citric acid. Certain temperature changes during the course of incubation were found to increase the yield of citric acid.The present investigation was undertaken to see if a simple method could be found to improve the yield of citric acid from blackstrap molasses, and we could obtain the yield of more than 70% from the untreated molasses using a newly isolated strain of Asp. niger. 相似文献
907.
Kei Arima Tadashi Sakamoto Chuji Araki Gakuzo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(3):356-361
A variety of microorganisms were tested for their extracellular l-asparaginase productivity and it was found that many bacteria, fungi and yeasts are positive for it. Especially some strains in the genera Pseudomonas, Candida and Rhodotorula were able to produce a large amounts of the enzyme. Escherichia coli, however, that contained intracellular enzyme was unable to produce extracellular one. In enzymological properties some differences were noted among these extracellular enzymes. Pseudomonas asparaginase showed glutaminase activity too, but the asparaginases of Candida and Rhodotorula were unable to hydrolyze glutamine. Candida l-asparaginase was most stable to heat-treatment. 相似文献
908.
909.
A biologically active substance which inhibits spawning of the starfish, Asterina pectinifera, has been isolated from gonads of the same organism and identified as l-glutamic acid. 相似文献
910.
The acid cyclization product from pyrethrosin has been proved to be a (1:1)-mixture of cyclopyrethrosin acetate containing a Δ3(4)-double bond and isocyclopyrethrosin acetate with a Δ4(15)-double bond through the reinvestigation. NMR and ORD studies on their derivatives led us to assign revised stereochemistry to pyrethrosin and its related compounds. 相似文献