title: Complete sequencing of the bla(NDM-1)-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens.
abstract: The complete sequence of the plasmid pNDM-1_Dok01 carrying New Delhi metallo-β-lactamase (NDM-1) was determined by whole genome shotgun sequencing using Escherichia coli strain NDM-1_Dok01 (multilocus sequence typing type: ST38) and the transconjugant E. coli DH10B. The plasmid is an IncA/C incompatibility type composed of 225 predicted coding sequences in 195.5 kb and partially shares a sequence with bla(CMY-2)-positive IncA/C plasmids such as E. coli AR060302 pAR060302 (166.5 kb) and Salmonella enterica serovar Newport pSN254 (176.4 kb). The bla(NDM-1) gene in pNDM-1_Dok01 is terminally flanked by two IS903 elements that are distinct from those of the other characterized NDM-1 plasmids, suggesting that the bla(NDM-1) gene has been broadly transposed, together with various mobile elements, as a cassette gene. The chaperonin groES and groEL genes were identified in the bla(NDM-1)-related composite transposon, and phylogenetic analysis and guanine-cytosine content (GC) percentage showed similarities to the homologs of plant pathogens such as Pseudoxanthomonas and Xanthomonas spp., implying that plant pathogens are the potential source of the bla(NDM-1) gene. The complete sequence of pNDM-1_Dok01 suggests that the bla(NDM-1) gene was acquired by a novel composite transposon on an extensively disseminated IncA/C plasmid and transferred to the E. coli ST38 isolate.
authors.affiliation: Laboratory of Bacterial Genomics, Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Sekizuka
authors.forename: Mari
authors.initials: M
authors.lastname: Matsui
authors.forename: Kunikazu
authors.initials: K
authors.lastname: Yamane
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Takeuchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Ohnishi
authors.forename: Akira
authors.initials: A
authors.lastname: Hishinuma
authors.forename: Yoshichika
authors.initials: Y
authors.lastname: Arakawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuroda
mesh_terms: D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D010802:Phylogeny; D010944:Plants / Q000201:enzymology* / Q000235:genetics; D010957:Plasmids / Q000235:genetics*; D001618:beta-Lactamases / Q000145:classification / Q000235:genetics*
chemical_list: D001618:beta-Lactamases; C552864:beta-lactamase NDM-1