title: A quorum-sensing autoinducer enhances the mexAB-oprM efflux-pump expression without the MexR-mediated regulation in Pseudomonas aeruginosa.
abstract: We have previously described that the quorum-sensing autoinducer, N-butyryl-L-homoserine lactone (C4-HSL) enhances mexAB-oprM expression, and this C4-HSL-mediated enhancement of mexAB-oprM expression was repressed by MexT, a positive regulator of the mexEF-oprN operon. In this study, we investigated the interaction between C4-HSL and mexR by using a knockout mutant. It was indicated that the C4-HSL-mediated enhancement of mexAB-oprM expression occurred without MexR-mediated regulation. Furthermore, it was observed that the C4-HSL-mediated enhancement of mexAB-oprM expression without the MexR-mediated regulation was repressed by MexT.
authors.affiliation: Institute of Applied Biochemistry, University of Tsukuba, Ibaraki, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Sawada
authors.forename: Hideaki
authors.initials: H
authors.lastname: Maseda
authors.forename: Taiji
authors.initials: T
authors.lastname: Nakae
authors.forename: Hiroo
authors.initials: H
authors.lastname: Uchiyama
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Nomura
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D026901:Membrane Transport Proteins / Q000096:biosynthesis; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; C118598:MexA protein, Pseudomonas aeruginosa; C118597:MexB protein, Pseudomonas aeruginosa; C423620:MexR protein, Pseudomonas aeruginosa; C092312:N-butyrylhomoserine lactone; C402263:OprM protein, Pseudomonas aeruginosa; C105708:OprN protein, Pseudomonas aeruginosa; D012097:Repressor Proteins; D015107:4-Butyrolactone