title: The mexR repressor of the mexAB-oprM multidrug efflux operon in Pseudomonas aeruginosa: characterization of mutations compromising activity.
abstract: Mutations in mexR yield a multidrug resistance phenotype in nalB mutants of Pseudomonas aeruginosa as a result of derepression of the mexAB-oprM multidrug efflux operon. MexR produced by several nalB strains carried single amino acid changes that compromised MexR stability or its ability to dimerize. Changes at residues L95 and R21, however, produced a stable MexR protein capable of dimerization and, thus, likely compromised DNA binding.
authors.affiliation: Department of Microbiology and Immunology, Queen's University, Kingston, Ontario, Canada K7L 3N6.
authors.forename: Lateef
authors.initials: L
authors.lastname: Adewoye
authors.forename: Ainsley
authors.initials: A
authors.lastname: Sutherland
authors.forename: Ramakrishnan
authors.initials: R
authors.lastname: Srikumar
authors.forename: Keith
authors.initials: K
authors.lastname: Poole
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D026901:Membrane Transport Proteins; D009154:Mutation; D009876:Operon; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D026901:Membrane Transport Proteins; C118598:MexA protein, Pseudomonas aeruginosa; C118597:MexB protein, Pseudomonas aeruginosa; C423620:MexR protein, Pseudomonas aeruginosa; C402263:OprM protein, Pseudomonas aeruginosa; D012097:Repressor Proteins