VIM-15 and VIM-16, two new VIM-2-like metallo-beta-lactamases in Pseudomonas aeruginosa isolates from Bulgaria and Germany.

Two Pseudomonas aeruginosa urine isolates from Bulgaria and Germany produced two new VIM-2 variants. VIM-15 had one amino acid substitution (Tyr218Phe) which caused a significant increase in hydrolytic efficiency. The substitution Ser54Leu, characterizing VIM-16, showed no influence on enzyme activity. Both genes were part of class I integrons located in the chromosome.