Comparative Genomic Analysis of Mobile Colistin Resistance Gene Mcr-9 in Salmonella Enterica.

The emergence and spread of mobile colistin resistance (mcr) family genes in Gram-negative bacteria limit our choice for treating multidrug-resistant bacterial infections. The mcr-9 gene was firstly reported in a multidrug-resistant (MDR) Salmonella (S.) enterica serovar Typhimurium isolate 1 Carroll L.M. Gaballa A. Guldimann C. Sullivan G. LO Henderson Wiedmann M. Identification of novel mobilized colistin resistance gene mcr-9 in a multidrug-resistant, colistin-susceptible Salmonella enterica serotype Typhimurium isolate. mBio. 2019; 10 (-19): e00853 Crossref PubMed Scopus (197) Google Scholar and subsequently identified in human gut microbiomes and clinical pathogens across at least five continents recently published in this journal. 2 Wang Y. Liu F. Zhu B. Gao G.F. Metagenomic data screening reveals the distribution of mobilized resistance genes tet(X), mcr and carbapenemase in animals and humans. J Infect. 2020; 80: 121-142 Scopus (9) Google Scholar , 3 Tyson G.H. Li C. Hsu C.H. Ayers S. Borenstein S. Mukherjee S. Tran T.T. McDermott P.F. Zhao S. The mcr-9 gene of Salmonella and E. coli is not associated with colistin resistance in the United States. Antimicrob Agents Chemother. 2020; 64 (-20): e00573 Crossref PubMed Scopus (18) Google Scholar –5 Cha M.H. Woo G.J. Lee W. Kim S.H. Woo J.H. Kim J. Ryu J.G. Kwak H.S. Chi Y.M. Emergence of transferable mcr-9 gene-carrying colistin-resistant Salmonella enterica Dessau ST14 isolated from retail chicken meat in Korea. Foodborne Pathog Dis. 2020; 17: 720-727 Crossref PubMed Scopus (11) Google Scholar . In this study, we reported the identification of mcr-9 in 60 S. enterica strains isolated from human, animal, and food.