title: Complex dissemination of the diversified mcr-1-harbouring plasmids in Escherichia coli of different sequence types.
abstract: The emergence of the mobilized colistin resistance gene, representing a novel mechanism for bacterial drug resistance, challenges the last resort against the severe infections by Gram-negative bacteria with multi-drug resistances. Very recently, we showed the diversity in the mcr-1-carrying plasmid reservoirs from the gut microbiota. Here, we reported that a similar but more complex scenario is present in the healthy swine populations, Southern China, 2016. Amongst the 1026 pieces of Escherichia coli isolates from 3 different pig farms, 302 E. coli isolates were determined to be positive for the mcr-1 gene (30%, 302/1026). Multi-locus sequence typing assigned no less than 11 kinds of sequence types including one novel Sequence Type to these mcr-1-positive strains. PCR analyses combined with the direct DNA sequencing revealed unexpected complexity of the mcr-1-harbouring plasmids whose backbones are at least grouped into 6 types four of which are new. Transcriptional analyses showed that the mcr-1 promoter of different origins exhibits similar activity. It seems likely that complex dissemination of the diversified mcr-1-bearing plasmids occurs amongst the various ST E. coli inhabiting the healthy swine populations, in Southern China.
authors.affiliation: Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Qingjing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Zhencui
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Jingxia
authors.initials: J
authors.lastname: Lin
authors.affiliation: Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.|Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
authors.forename: Xiuna
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China.
authors.forename: Xianbo
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Youjun
authors.initials: Y
authors.lastname: Feng
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002681:China; D003091:Colistin / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D029968:Escherichia coli Proteins / Q000235:genetics*; D019143:Evolution, Molecular; D005243:Feces / Q000382:microbiology; D000069196:Gastrointestinal Microbiome; D041981:Gastrointestinal Tract / Q000382:microbiology; D015964:Gene Expression Regulation, Bacterial; D005838:Genotype; D055029:Inverted Repeat Sequences; D009666:Nose / Q000382:microbiology; D010641:Phenotype; D010957:Plasmids / Q000235:genetics*; D011401:Promoter Regions, Genetic; D034421:Sus scrofa; D014158:Transcription, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; C000614037:MCR-1 protein, E coli; D003091:Colistin
keywords: Immune response; Immunity; Immunology and Microbiology Section; MCR-1; diversity; sequence type (ST)