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1.
This report shows the results of the reinvestigation of tRNA phosphorylation in E. coli. The phosphorylation did not occur on suppressor seryl-tRNA but occurred on other tRNA species. The activity of tRNA phosphorylation was found in E. coli extracts and partially purified. On DEAE-Sephadex A50 and PAGE gel, the phosphorylated-tRNA showed a pattern different from that the natural suppressor serine tRNA. 相似文献
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Electron microscopic examination showed microtubular structures in FL cells infected with all 18 strains of HSV-2 examined, but not in cells infected with 9 strains of HSV-1. These structures were also detected in other cultured cells (Vero and Earle's L cells) infected with HSV-2, and also in vivo in cells, such as neuronal cells of the spinal ganglia and liver cells, of one-day-old suckling mice (DDD strain) infected with this type of virus. Thus the microtubules were consistently detected in cells productively infected with HSV-2. No other herpesviruses so far examined produced microtubular structures such as those observed in HSV-2 infected cells. 相似文献
4.
Daisuke Takamatsu Rie Arai Tohru Miyoshi-Akiyama Kayo Okumura Masatoshi Okura Teruo Kirikae Atsuko Kojima Makoto Osaki 《Applied and environmental microbiology》2013,79(12):3882-3886
Melissococcus plutonius is a fastidious honeybee pathogen, and the addition of KH2PO4 to culture medium is required for its growth. Using genome sequences and a newly developed vector, we showed that mutations in genes encoding Na+/H+ antiporter and cation-transporting ATPase are involved in the potassium requirement for growth. 相似文献
5.
Iwao Koyama Haruo Yamagami Toyoyasu Kuwae Munetsugu Kurata 《Prostaglandins & other lipid mediators》1982,23(6):777-785
The release of 6-keto-prostaglandin F1α (6KF1α)_and of thromboxane B2 (TXB2) from cells were investigated using mouse peritoneal exudate cells (PECs) and non-cultured peritoneal macrophages. They were prepared by adhesion to glass dishes and incubated for 1 hr at 37°C in 5% Co2 in air. Both the percentage of spreading macrophages and the release of 6KF1α and TXb2 increased in proportion to the incubation time. 6KF1α and TXB2 were released from the macrophages, not from the non-adherent cells. When PECs were incubated in silicon-coated glass dishes, the spreading of macrophages was hardly detected and lower amounts of 6KF1α and TXB2 were released from these cells compared with cells incubated in non-treated glass dishes. These findings suggest that adhesion with the correlated spreading of macrophages on glass dishes serve as a considerable physical factor for the release of 6KF1α and TXB2. 相似文献
6.
The second (index finger) to fourth (ring finger) digit length ratio (2D:4D) is known to be a putative marker of prenatal exposure to testosterone. It has been reported that fetal and adult testosterone may be critical for development of physical and mental traits such as cardiovascular system, reaction time, aggressiveness and masculinity. Testosterone-driven attributes are associated with success in male-to-male physical competition, which may be proxied by ability in sports. Many researchers have found that 2D:4D is sexually dimorphic and is a negative correlate of athletic performance. This study aims to investigate the associations of 2D:4D with measures of power as another possible testosterone-associated trait using ability in sumo wrestling as a proxy for male physical competitiveness. The measures of sumo performance comprised the sumo ranks and winning percentages of 142 Japanese professional sumo wrestlers. We found that sumo wrestlers with low 2D:4D had higher sumo ranks and better winning records. The significant negative associations between 2D:4D and the athletic prowess of sumo wrestlers provide further evidence of the possible link between high testosterone levels and muscle strength. The relatively small effect sizes found in this study, however, imply that 2D:4D may be a weaker predictor for sports requiring explosive power than for those requiring endurance. 相似文献
7.
Melissa Carrillo Suraj Pandey Juan Sanchez Moraima Noda Ishwor Poudyal Luis Aldama Tek Narsingh Malla Elin Claesson Weixiao Yuan Wahlgren Denisse Feliz Vukica Šrajer Michał Maj Leticia Castillon So Iwata Eriko Nango Rie Tanaka Tomoyuki Tanaka Luo Fangjia Marius Schmidt 《Structure (London, England : 1993)》2021,29(7):743-754.e4
8.
Yu Kitadate David J. Jörg Moe Tokue Ayumi Maruyama Rie Ichikawa Soken Tsuchiya Eri Segi-Nishida Toshinori Nakagawa Aya Uchida Chiharu Kimura-Yoshida Seiya Mizuno Fumihiro Sugiyama Takuya Azami Masatsugu Ema Chiyo Noda Satoru Kobayashi Isao Matsuo Yoshiakira Kanai Shosei Yoshida 《Cell Stem Cell》2019,24(1):79-92.e6
9.
Tsubasa Ishida Rie Ito Jessica Clark Nicholas J. Matzke Yoshiyuki Sowa Matthew A. B. Baker 《Molecular microbiology》2019,111(6):1689-1699
The bacterial flagellar motor powers the rotation that propels the swimming bacteria. Rotational torque is generated by harnessing the flow of ions through ion channels known as stators which couple the energy from the ion gradient across the inner membrane to rotation of the rotor. Here, we used error‐prone PCR to introduce single point mutations into the sodium‐powered Vibrio alginolyticus/Escherichia coli chimeric stator PotB and selected for motors that exhibited motility in the presence of the sodium‐channel inhibitor phenamil. We found single mutations that enable motility under phenamil occurred at two sites: (i) the transmembrane domain of PotB, corresponding to the TM region of the PomB stator from V. alginolyticus and (ii) near the peptidoglycan binding region that corresponds to the C‐terminal region of the MotB stator from E. coli. Single cell rotation assays confirmed that individual flagellar motors could rotate in up to 100 µM phenamil. Using phylogenetic logistic regression, we found correlation between natural residue variation and ion source at positions corresponding to PotB F22Y, but not at other sites. Our results demonstrate that it is not only the pore region of the stator that moderates motility in the presence of ion‐channel blockers. 相似文献
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