The effect of mutations in the AmpC promoter region on β-lactam resistance from an Escherichia coli clinical isolate in a public sector hospital in KwaZulu-Natal, South Africa

Abstract

The ampC promoter and attenuator regions of an Escherichia coli clinical isolate from a public hospital in KwaZulu-Natal was investigated to detect the presence of mutations in these regions. The isolate was subjected to MIC determinations, IEF analysis, PCR for the presence of β-lactamases and sequencing of the ampC gene. Analysis of the ampC promoter and attenuator regions of the isolate showed that the isolate had mutations in the promoter region and this included insertions of nucleotides in the spacer region between the -10 and -35 Pribnow boxes. The insertion of an extra nucleotide in the spacer region between the -10 and -35 boxes affects the resistance of bacteria to β-lactam antibiotics.