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51.
Protochlorophyll(ide) was isolated from dark-grown wild typeand mutant C-2A' cells of Scenedesmus obliquus after dark incubationwith 5-aminolevulinate. Proto-chlorophyll(ide) was detectedin mutant cells grown heterotrophically at 29°C or at 21°C.At the latter temperature chlorophyll synthesis was significant.Regulation of chlorophyll synthesis in algae is discussed.
1Present address: Laboratory of Chemistry, Faculty of Medicine,Teikyo University, Otsuka, Hachioji, Tokyo 192-03, Japan. (Received July 14, 1980; ) 相似文献
52.
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
53.
Carbon dioxide enhanced chloroplast regeneration in glucose-bleachedcells of Chlorella protothecoides in the presence of CMU inthe light. Both the formation of chlorophyll and the synthesesof RNA and protein were considerably enhanced. The CO2 metabolism of algal cells during greening was investigatedusing 14C-bicarbonate as the tracer. Radiocarbon was largelyincorporated into purine and pyrimidine bases in nucleic acidand the arginine in protein, specifically at the crabon atomsderived from carbamylphosphate.
1Part of this investigation was reported at the conference onthe "Autonomy and biogenesis of mitochondria and chloroplasts"held at Canberra in 1969 (4). (Received August 19, 1975; ) 相似文献
54.
Hiromu Ohno Eiji Nakanishi Takeichiro Takamatsu 《Biotechnology and bioengineering》1976,18(6):847-864
This work is concerned with the optimization study of the semibatch fermentation by which an amino acid is produced. The particular fermentation studied is the synthesis of lysine by the auxotrophic mutant. Applying Green's theorem to the maximization problem was proposed, and it succeeded in determining the feed rate of the substrate that maximized the production rate of the desired product. 相似文献
55.
Eiji Hayase Takehiko Shibata Tadahiko Ando 《Biochemical and biophysical research communications》1975,62(4):849-855
An enzyme activity specific for UV-DNA1 was found in the extract of (Marburg 168). The enzyme preparation obtained from the extract by ammonium sulfate precipitation acts on UV-DNA endonucleolytically and induces single strand breaks. The number of single strand breaks introduced in DNA is proportional to UV dose. 相似文献
56.
Chloroplast-nucleus interactions were examined in cells of Euglenagracilis Z synchronized under photoautotrophic conditions. Thechloroplasts were localized near the cell periphery. At an earlystage of the cell cycle, however, some chloroplasts were transientlylocated in the inner space close to the nucleus. Electron microscopyusing serial cell sections revealed that the chloroplast formedprotrusions at several sites, which became associated with thenucleus. The outer membrane of the chloroplast envelope wasin contact, or at least continuous in part, with the outer membraneof the nuclear envelope at the sites of association, and densematerial was present in the chloroplast membrane. A chromosomewas close to each site of the association between these twoorganelles. Most of the chloroplasts including those in associationwith the nucleus were connected by fine bridges. The 4',6-diamidino-2-phenylindole-stainednucleoids in the chloroplast associated with the nucleus appearedto have a thread-like shape. There was another type of chloroplast-nucleusconnection, in which an intervening membranous body was in contactwith the outer part of the nuclear envelope on one side andwith the chloroplast envelope on the other side.
1 This work was reported at the 48th Annual Meeting of the BotanicalSociety of Japan, Kyoto, October, 1983. (Received June 5, 1984; Accepted November 20, 1984) 相似文献
57.
Diamine oxidase (DAO) (EC 1.4.3.6) was purified from pea epicotyls to homogeneity by the criterion of polyacrylamide gel electrophoresis (PAGE). The pu 相似文献
58.
Disk-gel-electrophoresis of the leghaemoglobin isolated frompea root nodules revealed two major (Lb I and Lb IV) and threeminor components. The ratio of the two major components (LbI/Lb IV) decreased with increasing age. This ratio was higherin the distal than in proximal region when nodules were cutinto distal and proximal sections. In young nodules, the incorporationof radioactive leucine into Lb I was much higher than into LbIV. In older nodules, the radioactivities were much higher inLb IV than in Lb I. These data suggest that the change in thisratio is due mainly to differences in the rates of biosynthesis. Two major components (Lb I and Lb IV) which were isolated separatelyhad different O2-binding affinities. The O2-binding affinityof the component synthesized mainly in older nodules (Lb IV)was higher than that of the component synthesized mainly inyoung nodules (Lb I). These results indicate that changes inthe relative contents of leghaemoglobin during nodule developmentcontribute to more effective nitrogen fixation which is mediatedby changes in the capacities of oxygen transport. (Received July 7, 1981; Accepted November 2, 1981) 相似文献
59.
60.
Yasuhito Hamaguchi Manabu Fujimoto Takashi Matsushita Kenzo Kaji Kazuhiro Komura Minoru Hasegawa Masanari Kodera Eiji Muroi Keita Fujikawa Mariko Seishima Hidehiro Yamada Ryo Yamada Shinichi Sato Kazuhiko Takehara Masataka Kuwana 《PloS one》2013,8(4)