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111.
112.
Tomomi Hidaka Masao Goda Tomohisa Kuzuyama Naomi Takei Makoto Hidaka Haruo Seto 《Molecular & general genetics : MGG》1995,249(3):274-280
The biosynthetic pathway for production of the antibiotic fosfomycin by Streptomyces wedmorensis consists of four steps including the formation of a C-P bond and an epoxide. Fosfomycin production genes were cloned from genomic DNA using S. wedmorensis mutants blocked at different steps of the biosynthetic pathway. Four genes corresponding to each of the biosynthetic steps were found to be clustered in a DNA fragment of about 5 kb. Nucleotide sequencing of a large fragment revealed the presence of ten open reading frames, including the four biosynthetic genes and six genes with unknown functions. 相似文献
113.
114.
Isolation and Characterization of Hardening-Induced Proteins in Chlorella vulgaris C-27: Identification of Late Embryogenesis Abundant Proteins 总被引:4,自引:0,他引:4
Honjoh Ken-ichi; Yoshimoto Makoto; Joh Toshio; Kajiwara Taishin; Miyamoto Takahisa; Hatano Shoji 《Plant & cell physiology》1995,36(8):1421-1430
Hardening-induced soluble proteins of Chlorella vulgaris BeijerinkIAM C-27 (formerly Chlorella ellipsoidea Gerneck IAM C-27) wereisolated and purified by two-dimensional high-performance liquidchromatography (2D-HPLC) on an anion-exchange column, with subsequentreversed-phase chromatography. Some of the proteins were resolvedby SDS-PAGE, characterized by amino-terminal sequencing andidentified by searching for homologies in databases. Separationof the soluble proteins during the hardening of Chlorella bya combination of 2D-HPLC and SDS-PAGE revealed that at least31 proteins were induced or increased in abundance. Of particularinterest was the induction after 12 h of a 10-kDa protein withthe amino-terminal amino acid sequence AGNKPITEQISDAVGAAGQKVGand the induction after 6 h of a 14-kDa protein with the amino-terminalsequence ALGEESLGDKAKNAFEDAKDAVKDAAGNVKEAV. The amino-terminalsequences of these proteins indicated that they were homologousto late embryogenesis abundant (LEA) proteins. Furthermore,the level of a 22-kDa protein also increased after 12 h. Theamino-terminal sequence of this protein, AAPLVGGPAPDFTAAAVFD,indicated that it was homologous to thioredoxin peroxidase. (Received June 9, 1995; Accepted September 12, 1995) 相似文献
115.
Alejandro Vazquez-Tello Makoto Hidaka Takeshi Uozumi 《Plant Cell, Tissue and Organ Culture》1995,40(2):169-177
Embryogenic cell suspensions of Lavatera thuringiaca L. were established from leaf petiole and shoot regeneration was achieved when cells were plated on medium without growth regulators. We tested three methods for protoplast culture, isolated from a one-year old embryogenic cell suspension, to determine the best conditions for L. thuringiaca protoplast culture and shoot regeneration. The highest protoplast plating efficiency was obtained with the agaroseembedded method, reaching 30%, while the nursing culture method gave 5% when the protoplasts were plated over Whatman paper No. 2. However, the same nursing culture failed to produce protoplast-derived microcalluses when the protoplasts were plated on a nitrocellulose filter. The liquid thin layer method gave the lowest plating efficiency with only 0.5%. Shoot regeneration from protoplast-derived microcalluses was achieved in two steps; first, globular embryo development was favored in medium low in auxin (2,4-d and BA at 0.01 and 0.05 mg 1-1, respectively), second, the globular embryos further differentiate into shoots in medium without growth regulators or in medium containing GA3 (0.5 to 1.0 mg 1-1).Abbreviations 2,4-d
2,4-dichlorophenoxyacetic acid
- BA
benzyladenine
- GA3
gibberellic acid
- NAA
-naphthaleneacetic acid
- IBA
indole-3-butyric acid 相似文献
116.
Makoto Handa Akira Suzuki Sadayuki Shoji Kuninobu Kasuga Kunihisa Sogabe 《Inorganica chimica acta》1995,230(1-2):41-44
A vanadyl complex with perfluorinate phthalocyanine, VOPcF16, was prepared. The monomer-dimer solvent dependence was confirmed based on the solvent effect for the Q-band position-that is, VOPcF16 exists as a monomer in a nonpolar solvent such as benzene, but dimerizes in a polar solvent such as acetone. Electron spin resonance data also supported the solvent dependence found. In addition, the substituent effect of fluorine atoms on the redox properties was investigated by measuring the cyclic voltammograms in dichloromethane. On the reduction side, three redox couples were observed, the first two of which were assigned as being due to the reduction of the phthalocyanine ring (to LUMO), whose potentials are 0.4–0.5 V higher than those of the tetra-t-butyl and octabutoxy derivatives, VOPc(t-Bu)4 and VOPc(O-n-Bu)8. 相似文献
117.
The inner layer of vitelline membrane is an investment of avian ovum at the time of ovulation, but its formation is poorly understood. In order to elucidate the origin of the inner layer of vitelline membrane, a 33 kDa protein, one of the components of the inner layer, was purified from quail eggs and polyclonal antibody was raised against this protein. The tissue distribution of protein interacted with the antibody was studied by Western blotting technique. No immunoreactive component could be observed in extracts of liver, kidney, heart, lung, small intestine, brain, infundibulum, albumen-secreting region of oviduct, uterus, and wall of small white follicles. The intensive band was detected in the granulosa layer, which was isolated from the large preovulatory follicles as a monolayer of granulosa cells sandwiched between the inner layer of vitelline membrane and the basal lamina. The granulosa cells isolated from the granulosa layer also reacted with this antibody. Theca layer had no immunoreactive components. The position of the band of the 33 kDa protein on SDS-PAGE was sifted to higher molecular weight in follicular tissues as compared with that in the laid eggs, indicating that the structural change of the protein occurs after ovulation. These studies indicate that the material reactive to the antibody raised against a 33 kDa protein of quail vitelline membrane is synthesized by the granulosa cells. 相似文献
118.
Aruto Yoshida Tomoka Hara Hiroshi Ikenaga Makoto Takeuchi 《Glycoconjugate journal》1995,12(6):824-828
By employing a bovine UDP-N-acetylgalactosamine: polypeptideN-acetylgalactosaminyl transferase (O-GalNAc transferase) cDNA as a probe, we isolated four overlapping cDNAs from a porcine lung cDNA library. Both the nucleotide sequence of the porcine cDNA and the predicted primary structure of the protein (559 amino acids) proved to be very similar to those of the bovine enzyme (95% and 99% identity, respectively). Transient expression of the clone in COS-7 cells, followed by enzymatic activity assays, demonstrated that this cDNA sequence encodes a porcine O-GalNAc transferase. The intracellular O-GalNAc transferase activity was increased approximately 100-fold by transfecting cells with the porcine cDNA.Abbreviations O-GalNAc transferase
UDP-N-acetylgalactosamine: polypeptideN-acetylgalactosaminyltransferase
- PCR
polymerase chain reaction
- SDS
sodium dodecyl sulfate
- PAGE
polyacrylamide gel electrophoresis
- GnT-III
UDP-N-acetylglucosamine: -mannoside -1,4N-acetylglucosaminyltransferase III 相似文献
119.
Changes in eicosapentaenoic acid content of Navicula saprophila, Rhodomonas salina and Nitzschia sp. under mixotrophic conditions 总被引:4,自引:0,他引:4
Three species of microalgae able to produce eicosapentaenoic acid(EPA) were collected from brackish and sea water around Japan.
The species were identified as Navicula saprophila, Rhodomonassalina and Nitzschia sp. EPA as a proportion of total fatty
acids increased in the presence of acetic acid for Rhodomonas salina and Nitzschia sp. However, Navicula saprophila displayed
the greatest productivity of EPA and the EPA content of its biomass was enhanced under mixotrophic conditions in the presence
of acetic acid.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
120.
Identification of three genetic loci controlling leaf senescence in Arabidopsis thaliana 总被引:23,自引:3,他引:20
Sung Aeong Oh Joon-Hyun Park Gyu In Lee Kyung Hee Paek Soon Ki Park Hong Gil Nam 《The Plant journal : for cell and molecular biology》1997,12(3):527-535
Four mutants that show the delayed leaf senescence phenotype were isolated from Arabidopsis thaliana . Genetic analyses revealed that they are all monogenic recessive mutations and fall into three complementation groups, identifying three genetic loci controlling leaf senescence in Arabidopsis . Mutations in these loci cause delay in all senescence parameters examined, including chlorophyll content, photochemical efficiency of photosystem II, relative amount of the large subunit of Rubisco, and RNase and peroxidase activity. Delay of the senescence symptoms was observed during both age-dependent in planta senescence and dark-induced artificial senescence in all of the mutant plants. The results indicate that the three genes defined by the mutations are key genetic elements controlling functional leaf senescence and provide decisive genetic evidence that leaf senescence is a genetically programmed phenomenon controlled by several monogenic loci in Arabidopsis . The results further suggest that the three genes function at a common step of age-dependent and dark-induced senescence processes. It is further shown that one of the mutations is allelic to ein2-1 , an ethylene-insensitive mutation, confirming the role of ethylene signal transduction pathway in leaf senescence of Arabidopsis . 相似文献