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91.
92.
本文报道了具有降血糖作用的人参多肽基因的设计及用固相亚磷酰胺法的合成。再以质粒pUC19作为克隆载体,以大肠杆菌JM101为受体菌,克隆了人参多肽基因,并成功地获得了克隆菌株。 相似文献
93.
Stabilization of a HemA-LacZ hybrid protein against proteolysis during carbon starvation in atp mutants of Salmonella typhimurium. 总被引:2,自引:2,他引:0 下载免费PDF全文
Transposon insertions that stabilize the beta-galactosidase activity of a HemA-LacZ hybrid protein following carbon starvation were mapped to the atp operon of Salmonella typhimurium. This effect is similar to that seen with nuo mutants defective in the energy-conserving type I NADH dehydrogenase. Insertions in several other genes, including such highly pleiotropic mutants as rpoS, polA, and hfq, were isolated with the same phenotypic screen, but they do not affect the beta-galactosidase activity of HemA-LacZ. All of these mutants act indirectly to alter the colony color of many different fusion strains on indicator plates. 相似文献
94.
Determination of the entire nucleotide sequence of the aphid 28S ribosomal RNA gene (28S rDNA) revealed that it is 4,147 by
in length with a G + C content of 60.3%. Based on the nucleotide sequence, we constructed a presumed secondary-structure model
of the aphid 28S rRNA which indicated that the aphid 28S rRNA is characterized by the length and high G + C content of its
variable regions. The G + C content of the aphid's variable regions was much higher than that of the entire sequence of the
28S rRNA, which formed a striking contrast to those ofDrosophila with the G + C content much lower than the entire 28S molecule. In this respect, the aphid 28S rRNA somewhat resembled those
of vertebrates. This is the third report of a complete large-subunit rRNA sequence from an arthropod, and the first 28S rRNA
sequence for a nondipterous insect.
Correspondence to: H. Ishikawa 相似文献
95.
96.
Chronic In Vivo Sodium Azide Infusion Induces Selective and Stable Inhibition of Cytochrome c Oxidase 总被引:2,自引:1,他引:1
M. Catherine Bennett Gary W. Mlady Young-Hwa Kwon †‡ Gregory M. Rose 《Journal of neurochemistry》1996,66(6):2606-2611
Abstract: The effect of chronic subcutaneous infusion of sodium azide on the activity of mitochondrial respiratory chain enzymes was investigated in Sprague-Dawley rats. Treatment with ∼1 mg/kg/h sodium azide induced chronic, partial inhibition of cytochrome c oxidase, whereas the activities of respiratory complexes I and III were not significantly affected. The inhibition of cytochrome c oxidase was evident by 7 days after infusion began, and the effect was stable for at least 3 weeks. The selectivity of azide for cytochrome c oxidase is discussed in the context of other findings of azide effects on enzymes. The results of the present study indicate that the sodium azide infusion paradigm described here provides a useful tool for the evaluation of selective and stable cytochrome oxidase inhibition in vivo. 相似文献
97.
Transdominant mutants of I kappa B alpha block Tat-tumor necrosis factor synergistic activation of human immunodeficiency virus type 1 gene expression and virus multiplication. 总被引:2,自引:1,他引:1 下载免费PDF全文
P Beauparlant H Kwon M Clarke R Lin N Sonenberg M Wainberg J Hiscott 《Journal of virology》1996,70(9):5777-5785
98.
A Bacillus subtilis gene for malate dehydrogenase (citH) was found downstream of genes for citrate synthase and isocitrate dehydrogenase. Disruption of citH caused partial auxotrophy for aspartate and a requirement for aspartate during sporulation. In the absence of aspartate, citH mutant cells were blocked at a late stage of spore formation. 相似文献
99.
100.
Toshihiko Fujita Daiji Kitagawa Yusaku Okuyama Yasutoshi Jin Yoshio Ishito Tadashi Inada 《Environmental Biology of Fishes》1996,46(4):351-364
Synopsis Fish assemblages at an artificial reef site, a natural reef site and a sandy-mud bottom site, on the shelf (depth 130 m) off Iwate Prefecture, northern Japan, were surveyed by using a bottom trammel net from May 1987 to March 1993. A total of 12 173 fishes of 48 species were recorded. Physiculus maximowiczi was dominant and comprised 69% of the total numerical abundance. Total fish number was lowest in March at all the 3 sites when P. maximowiczi migrated to deeper and warmer waters. Assemblage equitability and species diversity also varied seasonally in accordance with the abundance fluctuation of P. maximowiczi. P. maximowiczi, Alcichthys alcicornis and Hexagrammos otakii were more abundant at the artificial reef and natural reef sites, while Dexistes rikuzenius and Hemitripterus villosus were more abundant at the sandy-mud bottom site; total fish abundance was largest at the artificial reef site mainly due to the large number of P. maximowiczi. Species richness was similar among sites, but equitability, and consequently species diversity, was lowest at the artificial reef site. The main effect of the artificial reef seemed the attraction of P. maximowiczi from nearby bottoms, especially from natural rocky reefs; its large abundance determined the structure of the artificial reef fish community. 相似文献