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排序方式: 共有1133条查询结果,搜索用时 15 毫秒
1.
Abstract A novel mycoplasmal species designated as Mycoplasma penetrans has recently been isolated from patients infected with human immunodeficiency virus. The 16S rRNA gene from this mycoplasma was cloned and its nucleotide sequence determined. This sequence was aligned with previously published homologous sequences from several mycoplasmas and with related Gram-positive bacteria and a phylogenetic tree was constructed. The results indicate that M. penetrans belongs to the evolutionary group Pneumoniae. 相似文献
2.
Journal of Plant Research - Silicon (Si) accumulation differs greatly among plant species, as revealed by an increasing number of studies reporting whole-leaf Si concentration for a wide range of... 相似文献
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Tomomi Hidaka Masao Goda Tomohisa Kuzuyama Naomi Takei Makoto Hidaka Haruo Seto 《Molecular & general genetics : MGG》1995,249(3):274-280
The biosynthetic pathway for production of the antibiotic fosfomycin by Streptomyces wedmorensis consists of four steps including the formation of a C-P bond and an epoxide. Fosfomycin production genes were cloned from genomic DNA using S. wedmorensis mutants blocked at different steps of the biosynthetic pathway. Four genes corresponding to each of the biosynthetic steps were found to be clustered in a DNA fragment of about 5 kb. Nucleotide sequencing of a large fragment revealed the presence of ten open reading frames, including the four biosynthetic genes and six genes with unknown functions. 相似文献
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Tomomi Nakamoto 《Journal of plant research》1995,108(1):71-75
The growth of the primary seminal root of maize (Zea mays L.) is characterized by an initial negative gravitropic reaction and a later positive one that attains a plagiotropic liminal
angle. The effects of temperature and water potential of the surrounding soil on these gravitropic reactions were studied.
Temperatures of 32, 25, and 18C and soil water potentials of −5,−38, and −67 kPa were imposed and the direction of growth
was measured for every 1 cm length of the root. The initial negative gravitropic reaction extended to a distance of about
10cm from the graln. Higher temperatures reduced the initial negative gravitropic reaction. Lower soil water potential induced
a downward growth at root emergence. A mathematical model, in which it was assumed that the rate of the directional change
of root growth was a sum of a time-dependent negative gravitropic reaction and an establishment of the liminal angle, adequately
fitted the distance-angle relations. It was suggested that higher temperatures and/or a lower water potential accelerated
the diminution of the intitial negative gravitropic reaction. 相似文献
6.
Maruf Mohammad Akbor Koji Tomobe Tomomi Yamada Juhyon Kim Hiroki Mano Nobuyuki Kurosawa Kazuo Sasaki Yasuyuki Nomura Masaharu Isobe 《Biochemical and biophysical research communications》2013
The senescence-accelerated mouse prone 8 (SAMP8) strain exhibits age-related learning and memory deficits (LMD) at 2 months of age. Combined linkage analysis of 264 F2 intercross SAMP8 × JF1 mice and RNA-seq analysis identified Hcn1 gene out of 29 genes in the LMD region on chromosome 13. Hcn1 in SAMP8 strain showed 15 times less polyglutamine repetition compared to Japanese fancy mouse 1 (JF1). Whole cell patch clamp analysis showed that Hcn1 ion conductivity was significantly lower in SAMP8 compared to that of JF1, which may be associated with learning and memory deficiency. 相似文献
7.
Ken Hirano Yuichiro Yoshida Tomomi Ishido Naoji Moriya Yoshiyuki Mizushina Mitsuru Ishikawa 《Analytical biochemistry》2010,405(2):160-199
In the present study, we investigated mammalian polymerases that consecutively incorporate various fluorophore-labeled nucleotides. We found that rat DNA polymerase β (pol β) consecutively incorporated fluorophore-labeled nucleotides to a greater extent than four bacterial polymerases, Sequenase Version 2.0, VentR (exo-), DNA polymerase IIIα and the Klenow fragment, and the mammalian polymerases DNA polymerase α and human DNA polymerase δ, under mesophilic conditions. Furthermore, we investigated the kinetics of correct or mismatched incorporation with labeled nucleotides during synthesis by rat pol β. The kinetic parameters Km and kcat were measured and used for evaluating: (i) the discrimination against correct pair incorporation of labeled nucleotides relative to unlabeled nucleotides; and (ii) the fidelity for all nucleotide combinations of mismatched pairs in the presence of labeled or unlabeled nucleotides. We also investigated the effect of fluorophore-labeled nucleotides on terminal deoxynucleotidyl transferase activity of rat pol β. We have demonstrated for the first time that mammalian pol β can consecutively incorporate various fluorophore-labeled dNTPs. These findings suggest that pol β is useful for high-density labeling of DNA probes and single-molecule sequencing for high-speed genome analysis. 相似文献
8.
Haruyuki Nakayama-Imaohji Katsuhiko Hirota Hisashi Yamasaki Saori Yoneda Hirofumi Nariya Motoo Suzuki Thomas Secher Yoichiro Miyake Eric Oswald Tetsuya Hayashi Tomomi Kuwahara 《PloS one》2016,11(2)
Phase changes in Bacteroides fragilis, a member of the human colonic microbiota, mediate variations in a vast array of cell surface molecules, such as capsular polysaccharides and outer membrane proteins through DNA inversion. The results of the present study show that outer membrane vesicle (OMV) formation in this anaerobe is also controlled by DNA inversions at two distantly localized promoters, IVp-I and IVp-II that are associated with extracellular polysaccharide biosynthesis and the expression of outer membrane proteins. These promoter inversions are mediated by a single tyrosine recombinase encoded by BF2766 (orthologous to tsr19 in strain NCTC9343) in B. fragilis YCH46, which is located near IVp-I. A series of BF2766 mutants were constructed in which the two promoters were locked in different configurations (IVp-I/IVp-II = ON/ON, OFF/OFF, ON/OFF or OFF/ON). ON/ON B. fragilis mutants exhibited hypervesiculating, whereas the other mutants formed only a trace amount of OMVs. The hypervesiculating ON/ON mutants showed higher resistance to treatment with bile, LL-37, and human β-defensin 2. Incubation of wild-type cells with 5% bile increased the population of cells with the ON/ON genotype. These results indicate that B. fragilis regulates the formation of OMVs through DNA inversions at two distantly related promoter regions in response to membrane stress, although the mechanism underlying the interplay between the two regions controlled by the invertible promoters remains unknown. 相似文献
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Loc Van Nguyen Ryoji Takahashi Stephen Mwangi Githiri Tito O. Rodriguez Nobuko Tsutsumi Sayuri Kajihara Takasi Sayama Masao Ishimoto Kyuya Harada Keisuke Suematsu Tomomi Abiko Toshihiro Mochizuki 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):743-755