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111.
Susumu Asakawa Masayo Akagawa-Matsushita Hiroyuki Morii Yosuke Koga Koichi Hayano 《Current microbiology》1995,31(1):34-38
We isolated a methanogenic strain, designated as strain TMA (=DSM 9195), from an enrichment culture inoculated with a Japanese paddy field soil. Strain TMA was Gram positive and strictly anaerobic. Cell shape was pseudosarcina-like, and cells were nonmotile. The strain was able to use methylamines, methanol, H2–CO2, and acetate as substrates for methanogenesis, but did not utilize formate. The optimum temperature and optimum pH were 30–37°C and 6.5–7.5 respectively. The G+C content of the DNA was 42.1 mol %. Strain TMA had DNA-DNA hybridization values of more than 80% with Methanosarcina mazeii S-6T (T = type strain). On the basis of phenotypic and genotypic characteristics, we identified strain TMA as M. mazeii. This is the first methylotrophic methanogen isolated from a paddy field soil and identified to the species level. 相似文献
112.
Makoto Matsuoka Masanori Tamaoki Yuichi Tada Tatsuhito Fuyjimura Akemi Tagiri Naoki Yamamoto Yuriko Kano-Murakami 《Plant cell reports》1995,14(9):555-559
Transgenic rice plants (Oryza sativa cv. Nipponbare) carrying 1 or 2 copies of a rice homeobox gene, OSH1, under the control of the CaMV 35S promoter were generated. The transgene caused altered morphology of leaf, such as ligule-replacement and abnormal division of sclerenchyma cells. The phenotype of these leaves resembles that of maize leaf morphological mutant, Knotted 1, which is caused by duplication of the KN1 gene (Veit et al., 1990). The in situ hybridization analysis has revealed that the expression of endogenous OSH1 is mainly localized in developing vascular strands of stem. We have discussed the biological roles of OSH1 in rice based on these results. 相似文献
113.
Takahiro Morio Hiroyuki Adachi Kazuo Sutoh Kaichiro Yanagisawa Yoshimasa Tanaka 《Journal of plant research》1995,108(1):111-114
Using a plasmid pBsr2 which carries a blasticidin S-resistant gene, we have improved the method of REMI (restriction enzyme-mediated
integration) provided for insertional mutagenesis inDictyostelium discoideum (bsr-REMI). To confirm usefulness of thebsr-REMI, transformation efficiency, copy number of integrated DNA, and randomness of integration into genome were examined. 相似文献
114.
The Δ9-desaturase system in liver microsome from rats treated chronically with ethanol was studied. Stearoyl-CoA desaturase activity decreased by 80% and palmitoyl-CoA desaturase activity was not detectable in microsomes from ethanol-fed rats, while activities of electron transport components such as NADH-cytochrome c and NADH-ferricyanide reductases remained unchanged. However, chronic ethanol administration resulted in an adaptive induction of the activity of NADPH-cytochrome c reductase and the contents of cytochrome b5 and P-450. The activity of the terminal component (cyanide-sensitive factor; CSF) of the desaturase system was greatly depressed by ethanol treatment. The NADH/NAD ratio in microsomes of ethanol-fed rats increased over 2-fold. These results suggest that, during chronic ethanol ingestion, decreased activities of Δ9-desaturases are due mainly to a decreased content of the terminal component of the desaturase system. 相似文献
115.
116.
The effects of several electron transport inhibitors on themagnitude and kinetics of cytochrome f oxidation induced byflash illumination were studied in the - and -band regions.On the flash excitation only a fraction of cytochrome f presentin the chloroplasts was oxidized with a half time of 0.1 to0.3 msec and then reduced with a half time of 10 to 25 msec. Dibromothymoquinone (DBMIB) at concentrations which severelysuppressed the reduction of cytochrome f approximately doubledthe magnitude of cytochrome f oxidation caused by a flash, mainlyby inducing an additional slow oxidation of cytochrome f witha half time longer than 1 msec. Enhancement of the cytochromef oxidation was also observed in the presence of bathophenanthroline.Such enhanced oxidation in duced by the two inhibitors was largelydiminished with the addition of reduced 2,6-dichlorophenolindophenolwhich accelerated cytochrome f reduction. In contrast, the inhibitionof cytochrome f reduction by 3-(3,4-dichlorophenyl)-1,1-dimethylurea(DCMU) was not associated with an increase in the magnitudeof cytochrome f oxidation. However, addition of DBMIB to theDCMU-poisoned chloroplasts enhanced cytochrome f oxidation,suggesting that this is related to a block of the electron transportbetween plastoquinone and cytochrome f. The results are explainedby assuming the occurrence of an electron carrier between plastoquinoneand cytochrome f. (Received May 10, 1978; ) 相似文献
117.
Linkage of Mercury, Cadmium, and Arsenate and Drug Resistance in Clinical Isolates of Pseudomonas aeruginosa 总被引:10,自引:4,他引:6
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Hideomi Nakahara Tomoaki Ishikawa Yasunaga Sarai Isamu Kondo Hiroyuki Kozukue Simon Silver 《Applied microbiology》1977,33(4):975-976
Of the 787 isolates, 99.8% were metal resistant, with most (99.5%) showing multiple resistance. Fifty-three percent of the isolates were both metal and drug resistant, whereas only 19% were metal resistant and drug sensitive. 相似文献
118.
The levels of free amino acids in the cerebral cortex of acute and chronic uremic rats were examined. Amino acids significantly elevated were aspartate, glutamine, glycine, histidine, ornithine, phenylalanine, phosphoethanolamine and taurine, whereas 1-methyl histidine and 3-methyl histidine were specifically detected in uremic rats. Glutamate, arginine and carnosine disclosed a significant reduction. There was no change in the concentrations of γ-aminobutyrate and alanine. The above findings were essentially identical in both acute and chronic uremia. It was conjectured that these changes of amino acid levels in the brain might participate in the progress of uremic encephalopathy. 相似文献
119.
Plasma membranes were isolated from lactating bovine mammary gland. Two crude membrane fractions; medium/d 1.033 (light membrane) and 1.033/1.053 interfaces (heavy membrane), were obtained by Ficoll density gradient centrifugation of osmotically washed microsomal fraction. Two crude membranes were further purified separately by sucrose density gradient centrifugation. Both light and heavy membranes banded at a sucrose density of 1.14. The purified membranes appeared as heterogeneous smooth membrane vesicles on electron microscopy. The contaminating suborganelles were not detected. The yield of the purified membranes relative to the homogenate was 1.2%. The degree of purity of the membranes was shown by a great increase in the specific activity of 5′-nucleotidase over the homogenate of 20-fold for light membrane and of 16-fold for heavy membrane. The relative activities of Mg2+-ATPase, (Na+ + K+)-ATPase, γ-glutamyl transpeptidase, phosphodiesterase I, akaline phosphatase and xanthine oxidase were also high (12–18-times) and nearly 20% of these enzymes was recovered. The activity of marker enzyme for mitochondria, endoplasmic reticulum and Golgi apparatus was very low, while that of acid phosphatase for lysosome was relatively high (5-times). DNA and RNA contents were very low. The major polypeptides rich in other suborganelles were not detected profoundly in the membrane fraction and the polypeptide compositions in both light and heavy membranes were similar upon SDS-polyacrylamide gel electrophoresis. 相似文献
120.
Hiroyuki Horitsu Yasushi Takahashi Junkō Tsuda Keiichi Kawai Yoshio Kawano 《Applied microbiology and biotechnology》1983,18(6):358-360
Summary Living Aspergillus terreus cells were entrapped in polyacrylamide gels and employed in both replacement batch and continuous column reactors to produce itaconic acid from glucose.With the replacement batch reactor, maximum itaconic acid productivity was observed under the following conditions: pH 2.50, temperature at 35°C, addition of NH4H2PO4 and MgSO4·7H2O. Using the continuous reactor, the maximum itaconic acid yield was 60 mg/h/40 g of gel. The biocatalyst activity or half-life was about 10 days. 相似文献