The surveillance of colistin resistance and mobilized colistin resistance genes in multidrug-resistant Enterobacteriaceae isolated in Japan

•The rate of colistin resistance in all strains was 7.7%.•The mcr-5 gene was detected in only one ESBL-producing Escherichia coli strain (1/273, 0.37%).•The ESBL-producing E. coli strain was the first clinical strain with mcr-5 in Japan.•The mcr-5 positive strain carried ESBL gene-carrying and mcr-5.1-carrying plasmids.•The mcr-9 gene was detected in three Enterobacter cloacae complex strains (3/273, 1.1%).