title: A Myxococcus xanthus rppA-mmrA double mutant exhibits reduced uptake of amino acids and tolerance of some antimicrobials.
abstract: Myxococcus xanthus RppA and MmrA are homologous to methyl-accepting chemotaxis proteins (MCPs) and to multidrug transporters, respectively. We reported previously that rppA-mmrA double mutant exhibited reduced colony expansion, agglutination, and polysaccharide levels. We have demonstrated here that the rppA-mmrA mutant also exhibited reduced amino acid uptake. Furthermore, the double mutant appeared to be more susceptible to some antimicrobial agents, such as streptomycin, ethidium bromide and norfloxacin, than the wild-type. These phenotypes were not shown in the rppA or mmrA single mutant. These results indicate that M. xanthus RppA and MmrA are also involved in the uptake of amino acids and efflux of some antimicrobial agents.
authors.affiliation: Department of Life Sciences, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan. kimura@ag.kagawa-u.ac.jp
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kimura
authors.forename: Saori
authors.initials: S
authors.lastname: Ishida
authors.forename: Hideki
authors.initials: H
authors.lastname: Matoba
authors.forename: Naoki
authors.initials: N
authors.lastname: Okahisa
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001692:Biological Transport; D004996:Ethidium / Q000494:pharmacology; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D000072236:Methyl-Accepting Chemotaxis Proteins; D008826:Microbial Sensitivity Tests; D009154:Mutation; D016941:Myxococcus xanthus / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D009643:Norfloxacin / Q000494:pharmacology; D013307:Streptomycin / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D004996:Ethidium; D009643:Norfloxacin; D013307:Streptomycin