First Report on Genome Analysis and Pathogenicity of Vibrio tubiashii FP17 from Farmed Ivory Shell (Babylonia areolata)

Ivory shell (Babylonia areolata) is a commercially important aquaculture species mainly found on the southeast coast of China. However, it has been greatly affected by vibriosis in recent years. In this study, FP17 (a potential pathogen) was isolated from dying ivory with “acute death syndrome” and confirmed as pathogen via infectious experiment. Furthermore, phylogenetic analysis based average nucleotide identity (ANI) sequencing 16S rRNA gene housekeeping genes (ftsz, gapA, gyrB, mreB, pyrH, rpoA, topA) indicated that identical to Vibrio tubiashii. Transmission electron microscopy showed curved short rod shape, single flagellum. Besides, calculated LD50 after intramuscular injection 2.11 × 106 CFU/g at 14 d. The genome strain consists two chromosomes one plasmid 5,261,336 bp 45.08% GC content, including 4824 open reading frames (ORFs) 150 non-coding RNAs (ncRNA). Genome mining revealed 120 candidate clusters, vibrioferrin flagellum-related proteins, are responsible for virulence. Comparative genomic genes, such pvs type Ⅵ secretion system protein (vas), specific V. tubiashii but not ATCC19109 strain. 92 antimicrobial resistance (AMR) tufA, tet(35), crp, etc., were mapped within virulence, consistent antibiotic susceptibility assay. This first study describe complete sequence infecting shell. genetic characteristics, virulence factors, also explored.