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991.
Yuki Minegishi Pierre‐Alexandre Gagnaire Jun Aoyama Pierre Bosc Eric Feunteun Katsumi Tsukamoto Patrick Berrebi 《Journal of Biogeography》2012,39(2):408-420
Aim The objective of this study was to reveal the present population structure and infer the gene‐flow history of the Indo‐Pacific tropical eel Anguilla bicolor. Location The Indo‐Pacific region. Methods The entire mitochondrial control region sequence and the genotypes at six microsatellite loci were analysed for 234 specimens collected from eight representative localities where two subspecies have been historically designated. In order to infer the population structure, genetic differentiation estimates, analysis of molecular variance and gene‐tree reconstruction were performed. The history of migration events and population growth was assessed using neutrality tests based on allelic frequency spectrum, coalescent‐based estimation of gene flow and Bayesian demographic analysis using control region sequences. Results Population structure analysis showed genetic divergence between eels from the Indian and Pacific oceans (FST = 0.0174–0.0251, P < 0.05 for microsatellites; ΦST = 0.706, P < 0.001 for control region), while no significant variation was observed within each ocean. Two mitochondrial sublineages that do not coincide with geographical regions were found in the Indian Ocean clade of a gene tree. However, these two sublineages were not differentiated at the microsatellite markers. The estimation of mitochondrial gene‐flow history suggested allopatric isolation between the Indian and Pacific oceans, and a possible secondary contact within the Indian Ocean after an initial population splitting. Bayesian demographic history reconstruction and neutrality tests indicated population growth in each ocean after the Indo‐Pacific divergence. Main conclusions Anguilla bicolor has diverged between the Indian and Pacific oceans, which is consistent with the classical subspecies designation, but is apparently genetically homogeneous in the Indian Ocean. The analysis of gene‐flow and demographic history indicated that the two mitochondrial sublineages observed in the Indian Ocean probably represent the haplotype groups of relict ancestral populations. A comparison with a sympatric congener suggested that absolute physical barriers to gene flow may not be necessary for population divergence in eels. 相似文献
992.
Yoichiro Hoshino Noboru Hayashi Shunji Taniguchi Naohiko Kobayashi Kenji Sakai Tsuyoshi Otani Akira Iritani Kazuhiro Saeki 《PloS one》2009,4(1)
Frozen animal tissues without cryoprotectant have been thought to be inappropriate for use as a nuclear donor for somatic cell nuclear transfer (SCNT). We report the cloning of a bull using cells retrieved from testicles that had been taken from a dead animal and frozen without cryoprotectant in a −80°C freezer for 10 years. We obtained live cells from defrosted pieces of the spermatic cords of frozen testicles. The cells proliferated actively in culture and were apparently normal. We transferred 16 SCNT embryos from these cells into 16 synchronized recipient animals. We obtained five pregnancies and four cloned calves developed to term. Our results indicate that complete genome sets are maintained in mammalian organs even after long-term frozen-storage without cryoprotectant, and that live clones can be produced from the recovered cells. 相似文献
993.
Isao Ōnishi Kyoji Yamasaki Katsumi Yamamoto 《Bioscience, biotechnology, and biochemistry》2013,77(3):177-184
The basic fraction contained in the essential oil of the Japanese Flue Cured Tobacco Leaf (before redrying) was investigated and 2,3′-dipyridyl was isolated and identified. While, on the other hand, the basic fraction of the essential oil of the aged Japanese Burley Tobacco Leaf was also investigated and nicotine was found to be the predominant constituent of that fraction. At the same time, a small amount of 2,3′-dipyridyl and myosmine was also isolated and identified. 相似文献
994.
Mari Ohta Junko Kitamura Tsutomu Fukuwatari Ryuzo Sasaki Katsumi Shibata 《Experimental Animals》2004,53(1):57-60
We have reported the effect of di(2-ethylhexyl)phthalate (DEHP) on the tryptophan (Trp)-niacin pathway in rats. To clarify the universal effect of DEHP on rodents, we studied whether DEHP also has an effect on Trp metabolism in mice. Mice were fed a niacin-free, 20% casein diet supplemented with DEHP for 21 days. Feeding with DEHP decreased the body weight gain and increased the liver weight in correlation with the dose level of DEHP. The administration of DEHP significantly increased the formation of quinolinic acid and the lower metabolites of the Trp-niacin pathway. The flux of niacin in the lower part of the Trp-niacin pathway in mice was enhanced by feeding with DEHP. 相似文献
995.
996.
Keisuke Wada Jyumpei Kobayashi Megumi Furukawa Katsumi Doi Takashi Ohshiro 《Bioscience, biotechnology, and biochemistry》2016,80(2):368-375
Effective utilization of microbes often requires complex genetic modification using multiple antibiotic resistance markers. Because a few markers have been used in Geobacillus spp., the present study was designed to identify a new marker for these thermophiles. We explored antibiotic resistance genes functional in Geobacillus kaustophilus HTA426 and identified a thiostrepton resistance gene (tsr) effective at 50 °C. The tsr gene was further used to generate the mutant tsrH258Y functional at 55 °C. Higher functional temperature of the mutant was attributable to the increase in thermostability of the gene product because recombinant protein produced from tsrH258Y was more thermostable than that from tsr. In fact, the tsrH258Y gene served as a selectable marker for plasmid transformation of G. kaustophilus. This new marker could facilitate complex genetic modification of G. kaustophilus and potentially other Geobacillus spp. 相似文献
997.
Junji Seto Shizuka Tanaka Toshihiko Murakata Hiroko Sato Naota Monma Reiko Arai Tatsuya Ikeda Katsumi Mizuta 《Microbiology and immunology》2019,63(7):280-284
In 2018, a patient was diagnosed with Shimokoshi type scrub typhus in Yamagata Prefecture, Japan. The causative pathogen was likely a variant type because 43 (8.3%) of 521 deduced amino acid sequences of the 56‐kDa type‐specific antigen (TSA) were different from those of the Shimokoshi prototype strain. The patient's paired sera showed low antibody titers against the Shimokoshi prototype strain. Two cases of scrub typhus reported in the Tohoku region during 2011–2012 also involved the same 56‐kDa TSA gene sequence. These findings suggest the presence of diversity in Shimokoshi type Orientia tsutsugamushi, which may impede the laboratory diagnosis of scrub typhus. 相似文献
998.
999.
Washing of PS II preparation by 1 M CaCl2 inactivates oxygenevolution without loss of bound manganese [Ono and Inoue (1983)FEBS Lett. 164: 255]. Most of the high-potential Cyt b550, whichamounts to about a half of the total Cyt b559 in untreated preparation,was converted to its low-potential form by CaCl2-washing. Theeffect was similar to that of Tris-washing. The peak positionof the gs band of the EPR spectrum of the CaCl2-washed preparation(g=2.95) was the same as that of the low potential form of untreatedpreparation but was slightly different from that of the Tris-washedor heat-treated preparation (g=2.98).
1 Present address: Department of Biology, Faculty of Science,Tokyo Metropolitan University, Fukazawa 2-1-1, Setagaya, Tokyo158, Japan. (Received November 14, 1984; Accepted January 30, 1985) 相似文献
1000.