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61.
A new acid carboxypeptidase was purified fromAspergillus oryzae grown on solid bran culture medium. The purified enzyme was found to be homogeneous by disc gel electrophoresis at pH 9.4 and isoelectric focusing. The enzyme was termedA. oryzae acid carboxypeptidase O-1 with isoelectric point 4.08. The substrate specificity of the new enzyme was investigated with proangiotensin, angiotensin, and bradykinin. Even when the proline was present at the penultimate position of the peptide, the enzyme rapidly hydrolyzed the carboxyterminal Pro-X (X=amino acid) peptide bond. TheK
m
andk
cat
values for angiotension (–Pro7–Phe8) at pH 3.7 and 30°C were 0.2 mM and 1.7 sec–1, respectively. 相似文献
62.
Michio Ohba Keiko Ono Keio Aizawa Setsuo Iwanami 《Journal of invertebrate pathology》1981,38(2):184-190
Bacteriological and serological characteristics of three Bacillus thuringiensis isolates obtained in Japan were investigated. They formed typical rhomboidal parasporal inclusions but flagellar (H) antigens of these isolates were different from those of the known 17 H serotypes of B. thuringiensis. The three isolates were divided into two new serotypes (serotypes 18 and 19). The serotype 18 isolate (3–71) produced thermostable exotoxin and the inclusions of this isolate were toxic to larvae of the silkworm, Bombyx mori, but nontoxic to larvae of the mosquito, Aedes aegypti. The other isolate (119-72) belonging to serotype 18 produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. However, other bacteriological properties of the isolate 119-72 were similar to those of the isolate 3–71. The serotype 19 isolate (117-72) produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. Acid production from saccharose and the production of brownish purple pigment were observed in the two serotype 18 isolates, while neither of them was observed in the serotype 19 isolate. In other 29 biochemical properties tested, there was no difference among the three isolates. Based on these characteristics, the following two subspecies names are proposed: Bacillus thuringiensis subsp. kumamotoensis (serotype 18) for the type strain 3–71 and Bacillus thuringiensis subsp. tochigiensis (serotype 19) for the type strain 117-72. 相似文献
63.
Torosachrysone and two new naphthalenic lactones, isotoralactone and cassialactone, were isolated from the seeds of Cassia obtusifolia. Their structures were established as 9,10-dihydroxy-7-methoxy-3-methylene-1H-naphtho(2,3-c)dihydropyrone-1-one and 8-methoxy-4-methyl-1-oxo-4,10,11-trihydroxy-naphtho(2,3-c)oxepin, respectively. 相似文献
64.
Eiji Ichishima Yoshinori Tsuruda Taro Ushijima Takehiko Nomi Shoji Suzuki Michio Takeuchi Akiko Yamane 《Current microbiology》1980,4(2):85-89
The enzymological, physical, and immunological properties of soluble and bound forms of intracellular acid carboxypeptidase
isolated from fresh mycelia ofAspergillus saitoi are reported. In the broken mycelia, about 60% of the total activity was found in the 2,000×g precipitate, with most of the remainder in the 100,000×g supernantant. The highly purified enzymes, Ia and Ib, from the 100,000×g supernatant were found to be homogeneous by such criteria as disc gel electrophoresis at pH 9.4 The bound enzyme, II, was
solubilized from the 2,000×g precipitate by self-digestion at pH 6.4 and was highly purified by chromotography. The two forms of intracellular enzymes,
the soluble enzymes (Ia and Ib) from the 100,00×g supernatant and the solubilized enzyme (II) from the 2,000×g precipitate, were closely related to, but not completely identical with, the extracellular acid carboxypeptidase. 相似文献
65.
Hiroko Ohba Hiroshi Inano Bun-ichi Tamaoki 《Biochemical and biophysical research communications》1981,103(4):1273-1280
Cytochromes P-450 and 5 were observed in the microsomal fraction of interstitial tissue of rat testes. Microsomal cytochrome 5 was reduced by the NADH coupled with the activities of Δ5-3β-hydroxysteroid dehydrogenase with Δ5-Δ4 isomerase through conversion of pregnenolone to progesterone. Activities of NADPH-supported 17α-hydroxylase and C-17-C-20 lyase which converted progesterone to androstenedione were stimulated by either the presence of NADH or the oxidative reaction by the dehydrogenase upon Δ5-3β-hydroxysteroids. Androstenedione production enhanced by the reaction of the dehydrogenase was decreased by addition of the antibody against NADH-cytochrome 5 reductase which was purified from rat hepatic microsomes, suggesting the active participation of cytochrome 5 in the androgen synthesis. 相似文献
66.
It was reported previously that two spherical flacherie viruses of silkworm, FVS I and FVS II, had been isolated from flacherie silkworm larvae and the nucleic acid of FVS II was RNA as suggested by the experiments of incorporation of [3H]-uracil. In this paper, it has been confirmed by biochemical methods that the nucleic acid of FVS I and FVS II is RNA. FVS I and FVS II were labeled with 32P in flacherie silkworms, and the viruses were analyzed by sucrose density gradient centrifugation. When the 32P-labeled compound in the viruses was treated with 0.5 n KOH, the acid-insoluble 32P-labeled compound changed to acid-soluble compounds. It was determined by paper chromatography and ion-exchange column chromatography that the alkali-decomposed compounds included four ribonucleotides. Therefore, the viral nucleic acid of FVS I and FVS II was determined to be RNA. The correlations between FVS I and FVS II particles were discussed, and it was suggested that FVS I and FVS II might be closely related or were the same viral species. 相似文献
67.
The reactions of 2'-O- or 3'-O-tosylated adenosines with Grignard reagents resulted in the formation of various products, which were deoxy or branched-chain deoxy sugar nucleosides, 1',2'-unsaturated nucleosides, 3'-deoxy-2'-keto sugar nucleosides, and so on. The convenient method for the synthesis of the 3'-deoxy-2'-keto adenine nucleoside is described. 相似文献
68.
69.
Etsuko Kawashima Yasuhiro Nakanishi Yusuke Terui Hideyuki Tomitori Keiko Kashiwagi Yusuke Ohba 《Nucleosides, nucleotides & nucleic acids》2013,32(4):196-205
Pyrrole polyamide-2′-deoxyguanosine 5′-phosphate hybrid (Hybrid 4) was synthesized and evaluated in terms of the inhibition of mouse mammary carcinoma FM3A cell growth. Hybrid 4 was found to exhibit dose-dependent inhibition of cell growth. 相似文献
70.
Hideaki Ohba 《Curtis's Botanical Magazine》2013,30(3):158-165
Pinus amamiana Koidz., an endangered pine from Yakushima and Tanegashima, is illustrated and described. Threats to its survival are discussed. 相似文献