TEM-145 and TEM-146 -lactamases produced by Escherichia coli isolates from state hospitals in KwaZulu-Natal, South Africa

Two Escherichia coli isolates which were isolated from the urine of patients in state hospitals in KwaZulu-Natal, South Africa were investigated to determine the sequence of the TEM -lactamases responsible for their resistance to -lactamase inhibitors. The isolates were subjected to MIC determinations, iso-electric focusing analysis, plasmid analysis, polymerase chain reaction (PCR) for the detection of -lactamase genes and sequencing of the blaTEM. Analysis of the nucleotide sequences revealed the presence of two novel TEM -lactamases, TEM-145 and TEM-146 which had the R244H mutation. Mutations at position 244 have been previously reported in other inhibitor-resistant TEMs (IRTs).