title: Characterization of a multiresistant mosaic plasmid from a fish farm Sediment Exiguobacterium sp. isolate reveals aggregation of functional clinic-associated antibiotic resistance genes.
abstract: The genus Exiguobacterium can adapt readily to, and survive in, diverse environments. Our study demonstrated that Exiguobacterium sp. strain S3-2, isolated from marine sediment, is resistant to five antibiotics. The plasmid pMC1 in this strain carries seven putative resistance genes. We functionally characterized these resistance genes in Escherichia coli, and genes encoding dihydrofolate reductase and macrolide phosphotransferase were considered novel resistance genes based on their low similarities to known resistance genes. The plasmid G+C content distribution was highly heterogeneous. Only the G+C content of one block, which shared significant similarity with a plasmid from Exiguobacterium arabatum, fit well with the mean G+C content of the host. The remainder of the plasmid was composed of mobile elements with a markedly lower G+C ratio than the host. Interestingly, five mobile elements located on pMC1 showed significant similarities to sequences found in pathogens. Our data provided an example of the link between resistance genes in strains from the environment and the clinic and revealed the aggregation of antibiotic resistance genes in bacteria isolated from fish farms.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Jinyu
authors.initials: J
authors.lastname: Wu
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Gang
authors.initials: G
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Feng
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017756:Aquaculture; D056449:Bacillales / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D001482:Base Composition; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000235:genetics; D019015:Geologic Sediments / Q000382:microbiology*; D020071:Interspersed Repetitive Sequences; D008969:Molecular Sequence Data; D010957:Plasmids; D017422:Sequence Analysis, DNA
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial