Cloning and characterization of motY, a gene coding for a component of the sodium-driven flagellar motor in Vibrio alginolyticus.
AUTOR(ES)
Okunishi, I
RESUMO
The bacterial flagellar motor is a molecular machine that couples proton or sodium influx to force generation for driving rotation of the helical flagellar filament. In this study, we cloned a gene (motY) encoding a component of the sodium-driven polar flagellar motor in Vibrio alginolyticus. Nucleotide sequence analysis revealed that the gene encodes a 293-amino-acid polypeptide with a single putative transmembrane segment that is very similar (94.5% identity) to the recently described MotY of V. parahaemolyticus. Their C-terminal domains were similar to the C-terminal domains of many peptidoglycan-interacting proteins, e.g., Escherichia coli MotB and OmpA, suggesting that MotY may interact with peptidoglycan for anchoring the motor. By using the lac promoter-repressor system, motY expression was controlled in V. alginolyticus cells. Swimming ability increased with increasing concentrations of the inducer isopropyl-beta-D-thiogalactopyranoside, and the swimming fraction increased after induction. These results are consistent with the notion that MotY is a component of the force-generating unit. V. alginolyticus motY complemented the motY mutation of V. parahaemolyticus. However, motY appeared to lack a region corresponding to the proposed motY promoter of V. parahaemolyticus. Instead, sequences similar to the sigma54 consensus were found in the upstream regions of both species. We propose that they are transcribed from the sigma54 -specific promoters.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=177953Documentos Relacionados
- MotY, a component of the sodium-type flagellar motor.
- The Sodium-Driven Flagellar Motor Controls Exopolysaccharide Expression in Vibrio cholerae
- Cysteine-Scanning Mutagenesis of the Periplasmic Loop Regions of PomA, a Putative Channel Component of the Sodium-Driven Flagellar Motor in Vibrio alginolyticus
- Putative channel components for the fast-rotating sodium-driven flagellar motor of a marine bacterium.
- A Slow-Motility Phenotype Caused by Substitutions at Residue Asp31 in the PomA Channel Component of a Sodium-Driven Flagellar Motor