Escherichia coli ST471 Producing VIM-4 Metallo-β-Lactamase in Colombia

Abstract

An Escherichia coli isolate sequence-type 471 (ST471) producing Verona integron-encoded metallo-β-lactamases (VIM)-4 was recovered from a rectal swab in a patient without travel records with osteomyelitis in Colombia. The isolate carried a class 1 integron-borne bla_VIM-4 gene with a 170-bp duplication in the 3' end of the gene, preceded by an aac(6')-Ib gene. The genetic environment of bla_VIM-4, bla_CMY-2, and sul2 genes showed similarities to the backbone of pKKp4, an IncA/C-type plasmid from a Klebsiella pneumoniae strain carrying bla_VIM-4 recovered in Kuwait. This is the first report of bla_VIM-4 in Enterobacterales in South America. Our results suggest that bla_VIM-4 gene was found on an IncA/C-type plasmid that could play a role in the spread of VIM-4 carbapenemase in Colombia.

Keywords: Escherichia coli; blaVIM-4; colonization; metallo-β-lactamase.

FIG. 1.

Alignment of the contig 7_1 of C2-70 isolate with the bla_VIM-4 region of Klebsiella pneumoniae KP3686 using Easyfig. The degree of genetic similarity between the sequences is depicted by the shaded area, and a scale indicating the degree of similarity is at the bottom right. The arrows represent the direction of transcription. Color images are available online.

FIG. 2.

Alignment of the contig 7_2, 23_1 and 7_1 of C2-70 isolate with the plasmid pKKp4-VIM from Klebsiella pneumoniae KKp4 using Easyfig. The degree of genetic similarity between the sequences is depicted by the shaded area, and a scale indicating the degree of similarity is at the bottom left. The arrows represent the direction of transcription. Genes are color coded depending on functional annotations at the bottom right. Alignment of the plasmid pKKp4-VIM (MF582638) harboring bla_VIM-4 with contigs 7_2, 23_1 and 7_1 of C2-70 with 52%, 23%, and 1% of coverage, respectively, by BLAST. The RI-1, RI-2, and RI-3 of pKKp4-VIM are also shown (black dotted lines). BLAST, basic local alignment search tool; VIM, Verona integron-encoded metallo-β-lactamases. Color images are available online.

FIG. 3.

Plasmid location of bla_VIM-4 on isolate C2-70 confirmed by S1-PFGE and southern hybridization with a bla_VIM probe. The plasmid bands in S1-PFGE are indicated by yellow arrows (left panel), a lambda ladder was included as reference (L). The plasmid band in which the bla_VIM-4 was detectable by southern hybridization using bla_VIM-4 probe is indicated by a red triangle (right panel). S1-PFGE, S1-pulsed-field gel electrophoresis. Color images are available online.