Emergence of Carbapenem-resistant Clinical Isolates of <i>Providencia</i> Species

Providencia is a genus of Gram-negative and non-spore forming bacteria belonging to the family Morganellaceae, which causes opportunistic infections in humans. Of 10 species identified date, three, P. alcalifaciens, rettgeri stuartii, are clinically important. alcalifaciens diarrhea, including outbreaks arising from food-borne infections, stuartii have been found cause hospital acquired urinary tract infections. Four isolates one isolate were obtained urine samples five patients Japan 2018. All highly resistant carbapenems. Three harbored blaIMP-70, encoding variant IMP-1 metallo-β-lactamase, with two amino acid substitutions (Val67Phe Phe87Val), copies blaIMP-1 blaIMP-11. Expression blaIMP-70 conferred carbapenem resistance Escherichia coli. Recombinant IMP-10, an Val67Phe but without Phe87Val, had significant higher hydrolytic activities against meropenem than recombinant IMP-1, indicating that substitution alters IMP-70. These results suggest species. become more carbapenems by acquisition or mutations blaIMP result substitutions, such as blaIMP-70.