M'brio aiginolyticus has a single po]ar flageltum responsibie for moti]ity by utilizing sodium motive force.The flagellar motor consists ofrotor and stator.It is thought that rotor-stator interaction that coup]es to Na' flux through the stator generates terque.However, the direct interaction between rotor and stator has not been detected clearly in vitro yet, presumably because such an interaction is weak and transient.Here, to establish a new method to deteet interactions between rotor and stator, we used Ftuorescence Cerrelation Spectroscopy
Uninterruptible Power Supply (UPS) Systans are extensively used by modern society for electrical support of computers, communications and other critical systems. Over the last few years, power transistorized UPS's have become much more practical and their numbers have increased accordingly. The performance of these transistorized UPS's has been further improved since they were described two years ago [1]. The inverter has been refined and simplified to the extent that the system now contains only one output transformer. The control circuitry now consists of a single circuit board. The improved rectifier has reduced input current distortion significantly.
We report here the direct evidence for the formation of alternative DNA structures in a plasmid DNA, termed pTIR10, containing a 0.23‐kb pyrimidine/purine‐biased (Pyr/Pur) stretch isolated from the rat genome. Long Pyr/Pur sequences are abundant in eukaryotic genomes, and they may modulate the biological activity of genes and genomes via formation of various types of triplex‐related structures. The plasmid DNA in sodium acetate buffer (pH 4.35) was deposited on APS‐modified mica, and after drying it was imaged with an atomic force microscope in air. Various types of thick protrusions have been observed on pTIR10 DNA. Structural parameters (width and height) of DNA molecules suggest that the alternative structures observed here are variations on the theme of an intramolecular triplex. The biological relevance of the structural features within Pyr/Pur stretches is discussed.
Journal Article Growth-dependent Topological Alteration of Plasmid DNA in Escherichia coli Topoisomerase Mutants Get access Mikio Kato, Mikio Kato Department of Life Science, College of Arts and Sciences, University of Osaka Prefecture, 1–1, Gakuen-cho, Sakai, Osaka 593, Japan To whom correspondence should be addressed. Search for other works by this author on: Oxford Academic Google Scholar Aya Furuno Aya Furuno Department of Life Science, College of Arts and Sciences, University of Osaka Prefecture, 1–1, Gakuen-cho, Sakai, Osaka 593, Japan Present address: Department of Chemistry, Graduate School of Science, Shizuoka University, Oya, Shizuoka 422, Japan. Search for other works by this author on: Oxford Academic Google Scholar Bioscience, Biotechnology, and Biochemistry, Volume 56, Issue 7, 1 January 1992, Pages 1130–1131, https://doi.org/10.1271/bbb.56.1130 Published: 01 January 1992 Article history Received: 05 November 1991 Published: 01 January 1992
Journal Article Effect of the Potential Triplex DNA Region on the In Vivo Expression of Bacterial β-Lactamase Gene in Superhelical Recombinant Plasmids Get access Mikio Kato, Mikio Kato *Department of Life Science, College of Integrated Arts and Sciences University of Osaka Prefecture1-1 Gakuen-cho, Sakai, Osaka 593 Search for other works by this author on: Oxford Academic PubMed Google Scholar Nobuyoshi Shimizu Nobuyoshi Shimizu **Department of Molecular Biology, Keio University School of Medicine35 Shinanomachi, Shinjuku-ku, Tokyo 160 Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Biochemistry, Volume 112, Issue 4, October 1992, Pages 492–494, https://doi.org/10.1093/oxfordjournals.jbchem.a123927 Published: 01 October 1992 Article history Received: 25 May 1992 Published: 01 October 1992
Abstract The effects of ionizing radiation on bacteria are generally evaluated from the dose-dependent survival ratio, which is determined by colony-forming ability and mutation rate. The mutagenic damage to cellular DNA induced by radiation has been extensively investigated; however, the effects of irradiation on the cellular machinery in situ remain unclear. In the present work, we irradiated Escherichia coli cells in liquid media with gamma rays from 60Co (in doses up to 8 kGy). The swimming speeds of the cells were measured using a microscope. We found that the swimming speed was unaltered in cells irradiated with a lethal dose of gamma rays. However, the fraction of motile cells decreased in a dose-dependent manner. Similar results were observed when protein synthesis was inhibited by treatment with kanamycin. Evaluation of bacterial swimming speed and the motile fraction after irradiation revealed that some E. coli cells without the potential of cell growth and division remained motile for several hours after irradiation.
