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781.
782.
Summary Photoreactivation effect on UV-induced allelic recombination has been examined using various combinations of leu
1 alleles in UV-sensitive and wild type diploid yeast, Saccharomyces cerevisiae. The frequencies of UV-induced heteroallelic reversion in UV-sensitive strains, presumably lacking dark-repair, are strikingly enhanced compared to those in wild type at the same doses under dark condition. However, these enhanced frequencies of reversion are diminished by photoreactivation almost to the level of those in wild type. The induced frequencies of homoallelic reversion (mutation) of relevant alleles are apparently lower than those of heteroallelic reversion. Phenotypic analysis for linked gene leu
1 on UV-induced heteroallelic revertants has shown that most of the revertants are of the nonreciprocal type recombination (mitotic gene conversion). These results would indicate that most of the dark-repairable damage leading to mitotic gene conversion after UV-light is due to pyrimidine dimers.On leave of absence from Radiation Center of Osaka Prefecture, Shinke-cho Sakai, Osaka, Japan. 相似文献
783.
Mami Tanaka Daiki Kumakura Sayaka Mino Hidetaka Doi Yoshitoshi Ogura Tetsuya Hayashi Isao Yumoto Man Cai Yu-Guang Zhou Bruno Gomez-Gil Toshiyoshi Araki Tomoo Sawabe 《Environmental microbiology》2020,22(8):3205-3217
Members of the family Vibrionaceae are generally found in marine and brackish environments, playing important roles in nutrient cycling. The Rumoiensis clade is an unconventional group in the genus Vibrio, currently comprising six species from different origins including two species isolated from non-marine environments. In this study, we performed comparative genome analysis of all six species in the clade using their complete genome sequences. We found that two non-marine species, Vibrio casei and Vibrio gangliei, lacked the genes responsible for algal polysaccharide degradation, while a number of glycoside hydrolase genes were enriched in these two species. Expansion of insertion sequences was observed in V. casei and Vibrio rumoiensis, which suggests ongoing genomic changes associated with niche adaptations. The genes responsible for the metabolism of glucosylglycerate, a compound known to play a role as compatible solutes under nitrogen limitation, were conserved across the clade. These characteristics, along with genes encoding species-specific functions, may reflect the habit expansion which has led to the current distribution of Rumoiensis clade species. Genome analysis of all species in a single clade give us valuable insights into the genomic background of the Rumoiensis clade species and emphasize the genomic diversity and versatility of Vibrionaceae. 相似文献
784.
Ueki Atsuko Takehara Toshiaki Ishioka Gen Kaku Nobuo Ueki Katsuji 《Applied microbiology and biotechnology》2017,101(22):8267-8277
Applied Microbiology and Biotechnology - Biological soil disinfestation (BSD) involves elimination of soil-borne plant pathogens in an environmentally friendly manner. Two anaerobic bacterial... 相似文献
785.
Characterization of the product of the gtfS gene of Streptococcus downei, a primer-independent enzyme synthesizing oligo-isomaltosaccharides 总被引:4,自引:0,他引:4
R R Russell M L Gilpin N Hanada Y Yamashita Y Shibata T Takehara 《Journal of general microbiology》1990,136(8):1631-1637
The gtfS gene, coding for a glucosyltransferase which synthesizes water-soluble glucan and previously cloned from Streptococcus downei strain MFe28 (mutans serotype h) into a bacteriophage vector, was subcloned into a plasmid vector. The gtfS gene products expressed in Escherichia coli were compared to the primer-independent, oligo-isomaltosaccharide synthase in Streptococcus sobrinus strain AHT (mutans serotype g) and shown to resemble it closely in molecular mass, isoelectric point, immunological properties, optimum pH and Km values. The glucans produced from sucrose by the gtfS gene products are alpha-1,6-linked linear oligo-isomaltosaccharides without any branching sites. A similar gtfS gene was also detected on chromosomal DNA from S. sobrinus strain AHT. 相似文献
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787.
788.
789.
Ei-ishi Takahashi Momoki Hirai Izuo Tobari Toyoko Utsugi Sayaka Nakai 《Mutation research》1982,94(1):115-123
To obtain information on the relation beteween yiels of chrmosome aberrations and dose at low-dose levels, experiments were conducted with 5, 10, 20, 30 and 50 rad of 137Cs γ-rays, on lymphocytes from man and crab-eating monkey (Macaca fascicularis). The dose-response relationship for dicentrics was obtained from the combined data of these low-dose experiments with those of our previous onse at high doses (100–400 rad) When the difference between observed yields and those expected from the linear-quadratic model were computed, the dose-response curve had a good fit for man, but not for the monkey. The linear regression lines between 0 and 30 rad were calculated, because the expected values of α/β for man and monkey would be about 100 and 60 rad.The human date gave a satisfactory fit to a linear model, i.e., a linear increase in aberration frequency with dose, whereas this was not so for those of the monkey. Furtyhermose, there was some suggestive evidence for the existence of plateau in dicentrics yields between 10 and 30 rad for the monkey and between 20 and 30 rad for human lymphocytes, but more data would be needed to verify this suggestion, particularly for human lymphocytes. 相似文献
790.
Yamamoto Yoshihiro; Aiba Hiroji; Baba Tomoya; Hayashi Kouji; Inada Toshifumi; Isono Katumi; Itoh Takeshi; Kimura Sigenobu; Kitagawa Masanari; Makino Kozo; Miki Takeyoshi; Mitsuhashi Nobutaka; Mizobuchi Kiyoshi; Mori Hirotada; Nakade Shinsuke; Nakamura Yoshikazu; Nashimoto Hiroko; Oshima Taku; Oyama Satoshi; Saito Noriko; Sampei Gen-ichi; Satoh Yu-ji; Sivasundaram Suharnan; Tagami Hideaki; Takahashi Hideyuki; Takeda Jun-ichi; Takemoto Keiko; Uehara Kazuyuki; Wada Chieko; Yamagata Sayaka; Horiuchi Takashi 《DNA research》1997,4(2):91-95
The contiguous 874.423 base pair sequence corresponding to the50.068.8 min region on the genetic map of the Escherichiacoli K-12 (W3110) was constructed by the determination of DNAsequences in the 50.057.9 min region (360 kb) and twolarge (100 kb in all) and five short gaps in the 57.968.8min region whose sequences had been registered in the DNA databases.We analyzed its sequence features and found that this regioncontained at least 894 potential open reading frames (ORFs),of which 346 (38.7%) were previously reported, 158 (17.7%) werehomologous to other known genes, 232 (26.0%) were identicalor similar to hypothetical genes registered in databases, andthe remaining 158 (17.7%) showed no significant similarity toany other genes. A homology search of the ORFs also identifiedseveral new gene clusters. Those include two clusters of fimbrialgenes, a gene cluster of three genes encoding homologues ofthe human long chain fatty acid degradation enzyme complex inthe mitochondrial membrane, a cluster of at least nine genesinvolved in the utilization of ethanolamine, a cluster of thesecondary set of 11 hyc genes participating in the formate hydrogenlyasereaction and a cluster of five genes coding for the homologuesof degradation enzymes for aromatic hydrocarbons in Pseudomonasputida. We also noted a variety of novel genes, including twoORFs, which were homologous to the putative genes encoding xanthinedehydrogenase in the fly and a protein responsible for axonalguidance and outgrowth of the rat, mouse and nematode. An isoleucinetRNA gene, designated ileY , was also newly identified at 60.0min. 相似文献