Emergence of carbapenem-resistant Providencia rettgeri and Providencia stuartti producing IMP-type metallo- β-lactamase in Japan.

Emergence of carbapenem-resistant Providencia rettgeri and Providencia stuartti producing IMP-type metallo-β-lactamase in Japan. Antimicrob Agents Chemother. 2020 Aug 17;: Authors: Iwata S, Tada T, Hishinuma T, Mari T, Satoshi O, Arai-Kuwahara K, Ogawa M, Shimojima M, Kirikae T Abstract Four Providencia rettgeri isolates and a Providencia stuartii isolate were obtained from urine samples of five patients in 2018 in Japan. All the isolates were resistant to imipenem and meropenem. Of them, three were highly resistant to both carbapenems with the minimum inhibitory concentrations (MICs) of 512 μg/ml. The three highly carbapenem-resistant isolates harbored bla IMP-70, encoding a variant of IMP-1 metallo-β-lactamase with two amino acid substitutions of Val67Phe and Phe87Val, and the other two harbored bla IMP-1 and bla IMP-11, respectively. Whole genome sequencing revealed that an isolate harbored two copies of bla IMP-1 on the chromosome, and that the other four harbored a copy of bla IMP-11 or bla IMP-70 in a plasmid. Expression of bla IMP-70 conferred carbapenem resistance in Escherichia coli Recombinant IMP-70 and an IMP-1 variant with Val67Phe, but not with Phe87Val, had significant higher hydrolytic activities against meropenem than recombinant IMP-1, indicating that an amino acid substitution of Val67Phe affects increased activities against meropenem in IMP-70. These results suggest that Providencia spp. become higher resistant...
Source: Antimicrobial Agents and Chemotherapy - Category: Microbiology Authors: Tags: Antimicrob Agents Chemother Source Type: research