CTXM and OXA Genes in Foodborne Bacteria from Cooked Street Foods Sold in the South Western States of Nigeria

http://www.doi.org/10.26538/tjnpr/v6i11.18

Abstract

The emergence of new antibiotic-resistant bacteria implicated in foodborne illnesses has led to increasing drug treatment failures that have become a great public health concern. This work identified the presence of CTXM and OXA resistance genes located on plasmids in some multiantibiotic resistant bacteria isolated from cooked street-vended food sold in South Western Nigeria using both phenotypic and molecular techniques. Fifty (50) bacteria were isolated and identified using conventional phenotypic techniques. Ceftazidime (30 μg), cefuroxime (30 μg), gentamicin (10 μg), ciprofloxacin (5 μg), ofloxacin (5 μg), cefixime (5 μg), amoxicillin (30 μg),
nitrofurantoin (300 μg), and augmentin (30 μg) were used to examine the isolates' resistance patterns. For bacteria resistant to four or more antibiotics, plasmid curing and plasmid DNA were extracted using conventional techniques. CTXM and OXA genes were subsequently amplified using the specific primers (PCR methods) from the extracted bacterial plasmid DNA. High resistance was observed to ceftazidime and augmentin (96%) as well as cefuroxime (86%), whereas susceptibility to ciprofloxacin, ofloxacin, gentamicin and nitrofurantoin was at 80%, 78%, 76% and 60% respectively. Fourteen of the isolates studied showed the presence of CTXM, fifteen carried OXA genes while five carried both CTXM and OXA genes on their plasmid. There is, therefore, a need for standard food quality policies guiding the establishment of ready-to-eat food outlets.