title: Efflux pumps, OprD porin, AmpC beta-lactamase, and multiresistance in Pseudomonas aeruginosa isolates from cystic fibrosis patients.
abstract: Expression of ampC, oprD, mexA, mexC, mexE, and mexX was studied in 25 Pseudomonas aeruginosa isolates from cystic fibrosis patients, including 14 isolates of the Liverpool epidemic strain. Overexpressed mexA or ampC and reduced oprD were associated with beta-lactam resistance. A specific combination of mexR, nalC, and nalD mutations occurred in 11 Liverpool strain isolates, including 7 with upregulated mexA.
authors.affiliation: Centre for Infections, Health Protection Agency, London, United Kingdom. MA.del.Mar.Tomas.Carmona@sergas.es
authors.forename: Maria
authors.initials: M
authors.lastname: Tomás
authors.forename: Michel
authors.initials: M
authors.lastname: Doumith
authors.forename: Marina
authors.initials: M
authors.lastname: Warner
authors.forename: Jane F
authors.initials: JF
authors.lastname: Turton
authors.forename: Alejandro
authors.initials: A
authors.lastname: Beceiro
authors.forename: German
authors.initials: G
authors.lastname: Bou
authors.forename: David M
authors.initials: DM
authors.lastname: Livermore
authors.forename: Neil
authors.initials: N
authors.lastname: Woodford
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D003550:Cystic Fibrosis / Q000150:complications*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D018432:Drug Resistance, Multiple / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D026901:Membrane Transport Proteins / Q000235:genetics*; D009154:Mutation; D018272:Porins / Q000235:genetics*; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation / Q000502:physiology; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; C118598:MexA protein, Pseudomonas aeruginosa; C470189:MexC protein, Pseudomonas aeruginosa; C402791:MexXY protein, Pseudomonas aeruginosa; D018272:Porins; C077157:OprD protein, Pseudomonas aeruginosa; C048795:AmpC beta-lactamases; D001618:beta-Lactamases