Identification of a Novel Plasmid-Mediated Carbapenemase-Encoding Gene, bla_VMB-2, in Vibrio diabolicus

Here, we characterized a carbapenem-resistant Vibrio diabolicus strain of shrimp origin with various experiments and bioinformatics analysis. A novel metallo-β-lactamase (MBL) gene, bla_VMB-2, that confers resistance to β-lactams, including meropenem and cephalosporins, was identified on a plasmid-borne composite transposon, ISShfr9-ISCR1-bla_VMB-2-bla_CARB-12-aadA1-ISShfr9, which is capable of generating a bla_VMB-2-bearing circular intermediate. ISShfr9 was found to be disseminated in multidrug-resistant (MDR) pathogens, arousing the concern of further transmission of a bla_VMB-2-bearing circular intermediate to clinical Enterobacterales strains via such insertion sequences, which warrants further investigations.