Vibrio metoecus sp.nov., a close relative of Vibrio cholerae isolated from coastal brackish ponds and clinical specimens.

TitleVibrio metoecus sp.nov., a close relative of Vibrio cholerae isolated from coastal brackish ponds and clinical specimens.
Publication TypeJournal Article
Year of Publication2014
AuthorsKirchberger PC, Turnsek M, Hunt DE, Haley BJ, Colwell RR, Polz MF, Tarr CL, Boucher Y
JournalInt J Syst Evol Microbiol
Date Published2014 Jun 27

A Gram staining negative, curved rod shaped bacterium with close resemblance to Vibrio cholerae, the etiological agent of cholera, was isolated over the course of several years from coastal brackish water (17 strains) and from clinical cases (two strains) in the United States. 16S rRNA gene identity with V. cholerae exceeds 98% yet an average nucleotide identity of around 86% and multi locus sequence analysis of six housekeeping genes (mdh, adk, gyrB, recA, pgi, rpoB) clearly delineates these isolates as a distinct genotypic cluster within the V. cholerae-V. mimicus clade. Most standard identification techniques do not differentiate this cluster of isolates from V. cholerae. Only amplification of the ompW gene using V. cholerae-specific primers and a negative Voges-Proskauer test shows a difference between the two clusters. Additionally, all isolated strains differ phenotypically from V. cholerae in their ability to utilize N-Acetyl-d-galactosamine and d-glucuronic acid as sole carbon sources. Furthermore, they are generally unable to infect the slime mold Dictyostelium discoideum, a widespread ability in V. cholerae. Based on these clear phenotypic differences that are not necessarily apparent in standard tests and, average nucleotide identity and phylogeny of protein-coding genes, we propose the existence of a new species, Vibrio metoecus sp. nov. with the type strain OP3H (LMG 27764, CIP 110643T). Due to its close resemblance to V. cholerae and the increasing number of strains isolated over the past several years, we suggest that V. metoecus sp. nov. is a relatively common Vibrio species that has been identified as atypical isolates of V. cholerae in the past. Its isolation from clinical samples also suggests strains of this species, like V. cholerae, are opportunistic pathogens.

Alternate JournalInt. J. Syst. Evol. Microbiol.
PubMed ID24972615