A comparative genomic and phenotypic study of Vibrio cholerae model strains using hybrid sequencing

Next-generation sequencing methods have become essential for studying bacterial biology and pathogenesis, often depending on high-quality, closed genomes. In this study, we utilized a hybrid sequencing approach to assemble the genome of C6706, a widely used <i>Vibrio cholerae</i> model strain. We present a manually curated annotation of the genome, enhancing user accessibility by linking each coding sequence to its counterpart in N16961, the first sequenced <i>V. cholerae</i> isolate and a commonly used reference genome. Comparative genomic analysis between <i>V. cholerae</i> C6706 and N16961 uncovered multiple genetic differences in genes associated with key biological functions. To determine whether these genetic variations result in phenotypic differences, we compared several phenotypes relevant to <i>V. cholerae</i> pathogenicity like genetic stability, acid sensitivity, biofilm formation and motility. Notably, <i>V. cholerae</i> N16961 exhibited greater motility and reduced biofilm formation compared to <i>V. cholerae</i> C6706. These phenotypic differences appear to be mediated by variations in quorum sensing and cyclic di-GMP signalling pathways between the strains. This study provides valuable insights into the regulation of biofilm formation and motility in <i>V. cholerae</i>.