| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
Author for correspondence: Michio Homma. Tel: -81 52 789 2991. Fax: -81 52 789 3001. e-mail: g44416a@nucc.cc.nagoya-u.ac.jp
ABSTRACT
PomA and PomB are integral membrane proteins and are essential for the rotation of the Na+-driven polar flagellar motor of Vibrio alginolyticus. On the basis of their similarity to MotA and MotB, which are the proton-conducting components of the H+-driven motor, they are thought to form the Na+-channel complex and to be essential for mechanochemical coupling in the motor. To investigate PomA function, random mutagenesis of the pomA gene by using hydroxylamine was carried out. We isolated 37 non-motile mutants (26 independent mutations) and most of the mutations were dominant; these mutant alleles are able to inhibit the motility of wild-type cells when greatly overexpressed. The mutant PomA proteins could be detected by immunoblotting, except for those with deletions or truncations. Many of the dominant mutations were mapped to the putative third or fourth transmembrane segments, which are the most conserved regions. Some mutations that showed strong dominance were in highly conserved residues. T186I is the mutation of a polar residue located in a transmembrane segment that might be involved in ion translocation. P199L occurred in a residue that is thought to mediate conformational changes essential for torque generation in MotA. These results suggest that PomA and MotA have very similar structures and roles, and the basic mechanism for torque generation will be similar in the proton and sodium motors.
This article has been cited by other articles:
|
|
 |
|
  M. Obara, T. Yakushi, S. Kojima, and M. Homma Roles of Charged Residues in the C-Terminal Region of PomA, a Stator Component of the Na+-Driven Flagellar Motor J. Bacteriol., May 15, 2008; 190(10): 3565 - 3571. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Yagasaki, M. Okabe, R. Kurebayashi, T. Yakushi, and M. Homma Roles of the Intramolecular Disulfide Bridge in MotX and MotY, the Specific Proteins for Sodium-Driven Motors in Vibrio spp. J. Bacteriol., July 1, 2006; 188(14): 5308 - 5314. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Fukuoka, T. Yakushi, and M. Homma Concerted Effects of Amino Acid Substitutions in Conserved Charged Residues and Other Residues in the Cytoplasmic Domain of PomA, a Stator Component of Na+-Driven Flagella J. Bacteriol., October 15, 2004; 186(20): 6749 - 6758. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Yakushi, S. Maki, and M. Homma Interaction of PomB with the Third Transmembrane Segment of PomA in the Na+-Driven Polar Flagellum of Vibrio alginolyticus J. Bacteriol., August 15, 2004; 186(16): 5281 - 5291. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. L. McCarter Polar Flagellar Motility of the Vibrionaceae Microbiol. Mol. Biol. Rev., September 1, 2001; 65(3): 445 - 462. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Asai, T. Shoji, I. Kawagishi, and M. Homma Cysteine-Scanning Mutagenesis of the Periplasmic Loop Regions of PomA, a Putative Channel Component of the Sodium-Driven Flagellar Motor in Vibrio alginolyticus J. Bacteriol., February 15, 2000; 182(4): 1001 - 1007. [Abstract] [Full Text]
|
|
|
|
|
|
Y. Asai, I. Kawagishi, R. E. Sockett, and M. Homma Hybrid Motor with H+- and Na+-Driven Components Can Rotate Vibrio Polar Flagella by Using Sodium Ions J. Bacteriol., October 15, 1999; 181(20): 6332 - 6338. [Abstract] [Full Text]
|
|
|
|
 |
|
 T. Yorimitsu, Y. Asai, K. Sato, and M. Homma Intermolecular Cross-linking between the Periplasmic Loop3-4 Regions of PomA, a Component of the Na+-driven Flagellar Motor of Vibrio alginolyticus J. Biol. Chem., September 29, 2000; 275(40): 31387 - 31391. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Sato and M. Homma Multimeric Structure of PomA, a Component of the Na+-driven Polar Flagellar Motor of Vibrio alginolyticus J. Biol. Chem., June 23, 2000; 275(26): 20223 - 20228. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |
