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1.
The psychrophile Clostridium sp. strain 69 contains a thermolabile triose phosphate isomerase which is inactivated rapidly in vitro and in vivo at 32 C. 相似文献
2.
The hexadeoxynucleotide analog, L-d(CGCGCG) composed of L-deoxyribose was synthesized and clearly shown to have the same conformation and dynamic properties with natural D-d(CGCGCG) except for chirality with CD spectra. This unnatural hexanucleotide was not cleaved by bleomycin, an antitumor DNA cleaving drug, but was able to bind to the DNA binding domain of bleomycin to a similar extent with the natural one. These results strongly suggest the importance of the other moiety than the DNA binding domain for the specific DNA recognition of bleomycin. Thus, L-oligonucleotides are useful for the study of DNA-drug interactions. 相似文献
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Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss 下载免费PDF全文
Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
7.
Isolation and characterization of a Bacillus strain capable of degrading the extracellular glucan from Cellulomonas flavigena strain KU 总被引:1,自引:0,他引:1
P.A. Bertram C.S. Buller G.C. Stewart J.M. Akagi 《Journal of applied microbiology》1993,74(4):460-466
P.A. BERTRAM, C.S. BULLER, G.C. STEWART AND J.M. AKAGI. 1993. Bacteria capable of utilizing the water-insoluble purified extracellular (1 → 3)-β-D-glucan (curdlan) from Cellulomonas flavigena strain KU by extracellular enzymes, were insolated and characterized. Enrichment cultures from a Winogradsky column were incubated anaerobically at 55C with curdlan as the sole source of carbon. Colonies surrounded by zones of clearing were selected from subcultures on solid curdlan media. One of the isolates was chosen for further study and identified by conventional methods, API-tests with calculation of similarity coefficients and ID-scores, estimation of mol% (G + C) and DNA-DNA liquid hybridization. The isolate is a facultatively anaerobic, facultatively thermophilic Bacillus sp. Identification at the species-level was not achieved. The isolate was characterized by some rare traits among bacilli, but it remains unresolved whether it defines a new taxon. 相似文献
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Purification of acetokinase from Desulfovibrio desulfuricans. 总被引:3,自引:1,他引:2
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To determine a possible mechanism causing male and female sterility in Cryptomeria japonica male and female cones were collected from a C. japonica, tree, ShinDai2, that lacks pollen release and fertile seeds and specimens were processed to examine the development of pollen
and female gametophytes using light microscopy and field emission scanning electron microscopy. Pre-meiotic development proceeded
normally, but the formation of aberrant meiotic products was observed in cones of both sexes. In sterile microsporangia, heterogeneous
microspore populations ranging from monads to polyads gave rise to mature pollen grains of non-uniform size. These pollen
grains were covered with an amorphous layer and adhered to each other. In addition, they remained in the microsporangia and
were not released even after the onset of pollen dissemination from fertile trees. In the ovules of sterile female cones,
megaspores with abnormal shapes, numbers, and sizes formed, and the development of female gametophytes was arrested at the
free nuclear or archegonium formation stages. These gametophytes collapsed, and no fertile embryo was generated. Results indicate
that meiotic defects are important in the sterility mechanism. 相似文献