Search

A novel 139,487-bp SXT/R391 integrative and conjugative element, ICEPmiChnBCP11, was characterized in Proteus mirabilisof swine origin in China. ICEPmiChnBCP11 harbors 20 different antimicrobial resistance genes, including the clinically important rRNA methyltransferase gene cfr, the extended-spectrum β-lactamase gene blaCTX-M-65, fosfomycin resistance gene fosA3, and fluoroquinolone resistance gene aac(6′)-Ib-cr.

ABSTRACTA colistin-resistant Escherichia coliisolate from a commercial poultry farm in China carried two colistin resistance genes, mcr-1and variant of mcr-3, in an IncP plasmid. The variant of the mcr-3gene, named mcr-3.11, encoded two amino acid substitutions compared with the mcr-3gene. A novel genetic structure, ISKpn40-mcr-3-dgkA-ISKpn40, might be the key element mediating the translocation of mcr-3through the formation of a circular form. The mcr-1and mcr-3genes, which are colocated on a plasmid, might pose a huge threat to public health.

ABSTRACTA novel 65.8-kb multidrug resistance transposon, designated Tn6450, was characterized in a Proteus mirabilisisolate from chicken in China. Tn6450contains 18 different antimicrobial resistance genes, including cephalosporinase gene blaDHA-1and fluoroquinolone resistance genes qnrA1and aac(6′)-Ib-cr. It carries a class 1/2 hybrid integron composed of intI2and a 3′ conserved segment of the class 1 integron. Tn6450is derived from Tn7via acquisition of new mobile elements and resistance genes.