Whole-genome comparison between reference sequences and oyster Vibrio vulnificus C-genotype strains

PLoS One. 2019 Jul 30;14(7):e0220385. doi: 10.1371/journal.pone.0220385. eCollection 2019.

Abstract

Whole-genome sequences of Vibrio vulnificus clinical genotype (C-genotype) from the CICESE Culture Collection, isolated from oysters, were compared with reference sequences of CMCP6 and YJ016 V. vulnificus C-genotype strains of clinical origin. The RAST web server estimated the whole genome to be ~4.8 Mb in CICESE strain 316 and ~4.7 Mb in CICESE strain 325. No plasmids were detected in the CICESE strains. Based on a phylogenetic tree that was constructed with the whole-genome results, we observed high similarity between the reference sequences and oyster C-genotype isolates and a sharp contrast with environmental genotype (E-genotype) reference sequences, indicating that the differences between the C- and E-genotypes do not necessarily correspond to their isolation origin. The CICESE strains share 3488 genes (63.2%) with the YJ016 strain and 3500 genes (63.9%) with the CMCP6 strain. A total of 237 pathogenicity associated genes were selected from reference clinical strains, where-92 genes were from CMCP6, 126 genes from YJ016, and 19 from MO6-24/O; the presence or absence of these genes was recorded for the CICESE strains. Of the 92 genes that were selected for CMCP6, 67 were present in both CICESE strains, as were as 86 of the 126 YJ016 genes and 13 of the 19 MO6-24/O genes. The detection of elements that are related to virulence in CICESE strains-such as the RTX gene cluster, vvhA and vvpE, the type IV pili cluster, the XII genomic island, and the viuB genes, suggests that environmental isolates with the C-genotype, have significant potential for infection.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Evolution, Molecular
  • Genome, Bacterial
  • Genotype
  • Ostreidae / microbiology*
  • Phylogeny
  • Vibrio vulnificus / classification*
  • Vibrio vulnificus / genetics
  • Virulence Factors / genetics
  • Whole Genome Sequencing / methods*

Substances

  • Virulence Factors

Grants and funding

Funding was provided by the Mexican Fondo Sectorial Salud-CONACyT, grant number S008-2009-1114024 to MLL-P as well as CICESE internal project 682110. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.