Genomic and Phenotypic Characteristics for Vibrio vulnificus Infections

Abstract

Background Vibrio vulnificus (VV) is a causative agent of foodborne diseases with high mortality. The aim of this study was to investigate the genomic and phenotypic profiles of VV. Methods Six VV isolates were collected and conducted whole-genome sequencing. Biofilm formation and anti-complement killing test were performed to evaluate the pathogenicity. Subsequently, 157 publicly available genomes of VV isolates were selected to determine the evolutionary relationship. Results The resistant genes norM and tet34 were identified in six isolates. A total of 156 virulence genes were identified. However, there is no obvious difference between strains isolated from blood and puncture fluid. The tendency of growth for six isolates decreased with the lapse of time, while the biofilm formation increased. The genes tadC and flp related to Flp pili were found in isolate 25506 and 30896, resulting in more obvious biofilm formation. In addition, the survival rate of 19656 was less than 20% due to lack of one genomic island including virulence genes ( impD-H, clpV-1 ) relevant to type VI secretion system (T6SS). Multi-locus sequence typing (MLST) revealed 95 different STs and 19 novel STs, indicating that the tendency of 163 isolates was sporadic. Further comparative genomics analysis clearly classified 163 isolates into three distinct evolutionary lineages. Conclusion VV infections were sporadic in humans and the environment. Virulence genes impD-H and clpV-1 related to T6SS were associated with pathogenicity phenotype of VV.

Membrane Efflux Pumps of Pathogenic Vibrio Species: Role in Antimicrobial Resistance and Virulence

“…The genome of V. vulnificus has 11 putative RND efflux pump-encoding genes, three of which (homologues of V. cholerae VexAB, VexCD, and AcrAB of E. coli) have been characterized by gene deletion studies [50]. A study identified the norM gene in whole-genome sequences of clinical V. vulnificus isolates [65]. While a mutant V. vulnificus lacking the vexAB homolog was more susceptible to erythromycin, acriflavine, ethidium bromide, and bile acid, deletion of acrAB homolog resulted in increased sensitivity of acriflavine alone, and vexCD deletion did not have any effect on the susceptibility to any of the antibiotics, dyes or bile acid [66].…”

Genetic characterizations, virulence, antimicrobial resistances and resistome analysis of vibrio spp. Isolated from farmed Asian sea bass (Lates Calcarifer) in Thailand

“…Furthermore, dfrA31 is an antibiotic resistance dihydrofolate reductase from an integron found in V. cholerae with target replacement as its resistance mechanism (Roberts et al, 2012;Zankari et al, 2012). Intriguingly, this gene can also be found in V. vulnificus isolates 25506, infecting humans in China (Zhang et al, 2021). Another interesting ARG that may affect SXT resistance was dfrA6 in CUVETCC1, which is also found in V. vulnificus (Vv1462) Hong Kong isolates from China.…”