Occurrence of extended-spectrum beta-lactamases in human and bovine isolates of Escherichia coli from Oyo state, Nigeria

  • Christiana Inwezerua University of Ibadan, Oyo state, Nigeria
  • Nuno Mendonça Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
  • Vera Calhau Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
  • Sara Domingues Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
  • Olufemi Ezekiel Adeleke University of Ibadan, Oyo state, Nigeria
  • Gabriela Jorge Da Silva Center of Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
Keywords: Escherichia coli, extended-spectrum beta-lactamases, plasmid-mediated quinolone resistance, genetic mobile elements

Abstract

Introduction: The main objective of the study was the molecular characterization of extended spectrum β-lactamases (ESBL) in Escherichia coli isolates collected from human and bovine samples in Oyo state, Nigeria.

Methodology: Between August 2010-2011, 114 E. coli isolates were collected from hospitals (n = 57) and bovine (n = 57). PCR and sequencing were used for identification of ESBLs, upstream sequences, plasmid-mediated quinolone resistance (PMQR) genes and class 1 integrons. Plasmid incompatibility groups were identified among ESBL-positive isolates by PCR. Genetic relatdness was assessed by rep-PCR and MLST. Transfer of ESBL determinants to the recipient strain E. coli J53 was performed by broth mating assays.

Results: CTX-M15 was the unique ESBL found in eight human isolates. Six CTX-M-15 producers also carry the aac(6’)-lb-cr gene and/or qnrB gene, and class 1 integrons. FIA, FIB, H11, H12, F, Y and K were the plasmid replicon types found. CTX-M-15 and PMQR determinants were transferred by conjugation in two E. coli assigned by MLST to ST131 and ST2695, a new allele.

Conclusions: The study highlights the dissemination hability of CTX-M-15 associated with PMQR, and the presence of class 1 integrons, able to capture additional genes, justifying the urgent need of antimicrobial resistance surveillance in Nigeria.

Downloads

Download data is not yet available.
Published
2014-06-11
How to Cite
1.
Inwezerua C, Mendonça N, Calhau V, Domingues S, Adeleke OE, Da SilvaGJ (2014) Occurrence of extended-spectrum beta-lactamases in human and bovine isolates of Escherichia coli from Oyo state, Nigeria. J Infect Dev Ctries 8:774-779. doi: 10.3855/jidc.3430
Section
Brief Original Articles