Interaction of the MexA and MexB components of the MexAB-OprM multidrug efflux system of Pseudomonas aeruginosa: identification of MexA extragenic suppressors of a T578I mutation in MexB.
A T578I mutation in MexB compromised the protein's contribution to antimicrobial resistance and negatively impacted its interaction with MexA. Mutations causing single amino acid changes in the C-terminal domain of MexA (R221H, L245F, E254K, and V259I) suppressed the antimicrobial susceptibility of a MexB(T578I)-expressing Pseudomonas aeruginosa strain and restored a MexA interaction with MexB(T578I). These data confirm the importance of the MexA C-terminal region in MexB binding and the likely significance of the region surrounding T587I of MexB in MexA interaction.
Nehme
Dominic
D
Department of Microbiology and Immunology, Queen's University, Kingston, Ontario, Canada.
Poole
Keith
K
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D017920:Antiporters / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018432:Drug Resistance, Multiple; D050576:Membrane Fusion Proteins / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
D017920:Antiporters; D050576:Membrane Fusion Proteins