title: Characterization of ESBL-producing Escherichia coli ST131 isolates from Port Elizabeth.
abstract: This study investigated resistance determinants and genetic relatedness in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates. PCR and DNA sequencing were used for screening isolates for blaCTX-M, blaTEM, and blaSHV (qnrA, qnrB, qnrC, qnrD, qnrS, aac(6)-lb-cr, and qepA) resistance genes and the sequence type 131 (ST131) clone. Genetic relatedness of E. coli ST131 isolates was determined by pulsed-field gel electrophoresis. Twelve isolates belonged to the ST131 clonal complex, while 8 were positive for aac(6')-lb-cr with qnrB1 also detected in 1 isolate. This study describes the first occurrence of CTX-M-9, qnrB1+aac(6')-lb-cr and CTX-M-3+qnrS1 among E. coli ST131 isolates from South Africa and illustrates their genetic diversity.
authors.affiliation: Department of Biochemistry and Microbiology, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa.
authors.forename: Kwanele
authors.initials: K
authors.lastname: Gqunta
authors.affiliation: Department of Biochemistry and Microbiology, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa. Electronic address: sharlene.govender@nmmu.ac.za.
authors.forename: Sharlene
authors.initials: S
authors.lastname: Govender
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000235:genetics; D014644:Genetic Variation; D006761:Hospitals; D006801:Humans; D007223:Infant; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013019:South Africa; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; C524438:QepA protein, E coli; C485384:Qnr protein, E coli; C412613:CTX-M-9 protein, E coli; C417271:beta-lactamase CTX-M-3; D001618:beta-Lactamases
keywords: ESBL-producing E. coli ST131; Genetic diversity