title: First Detection of OXA-10 Extended-Spectrum Beta-Lactamases and the Occurrence of mexR and nfxB in Clinical Isolates of Pseudomonas aeruginosa from Nigeria.
abstract: BACKGROUND
  The characterization of β-lactamase production in Pseudomonasaeruginosa is rarely reported in Nigeria. The objective of this study was to investigate the occurrence and characterize the different β-lactamases as well as mechanisms of fluoroquinolones resistance among P. aeruginosa isolated from various clinical sources from Nigeria.
  
  
  METHODS
  Isolates were investigated using PCR, RFLP and sequencing for the detection of various β-lactamases and efflux pump regulator genes.
  
  
  RESULTS
  The prevalence of OXA-10, AmpC, CTX-M and SHV in P. aeruginosa was 80, 70, 5 and 5%, respectively. The coexistence of blaOXA-10 with blaAmpC, blaSHV and blaCTX-M was reported in 40, 5 and 5% of isolates, respectively. The efflux pump regulator genes mexR and nfxB were both amplified in 45% of the OXA-10-positive isolates.
  
  
  CONCLUSIONS
  This is the first report of the characterization of OXA-10 extended-spectrum β-lactamases and occurrence of mexR and nfxB efflux regulator genes in clinical isolates of P. aeruginosa in Nigeria.
authors.forename: Bamidele T
authors.initials: BT
authors.lastname: Odumosu
authors.forename: Bola A
authors.initials: BA
authors.lastname: Adeniyi
authors.forename: Ram
authors.initials: R
authors.lastname: Chandra
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D024841:Fluoroquinolones / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D006801:Humans; D009549:Nigeria; D012150:Polymorphism, Restriction Fragment Length; D011552:Pseudomonas Infections / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification*; D012097:Repressor Proteins / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D024841:Fluoroquinolones; C423620:MexR protein, Pseudomonas aeruginosa; C077901:NfxB protein, Pseudomonas aeruginosa; D012097:Repressor Proteins; D014157:Transcription Factors; C055187:beta-lactamase PSE-2; C048795:AmpC beta-lactamases; D001618:beta-Lactamases