Ctp is required for virulence. (A) Cell surface hydrophobicity analysis using xylene, left to right is ATCC 17978, MR14, MR14C, and control; (B) cell surface hydrophobicity in terms of percentage. (C) Adhesion assay. (D) Invasion assay. The adhesion and invasion of the wild-type strain were set at 100%, and MR14 strain data are reported relative to these values. Data are from three independent experiments. (E) Two groups, each consisting of 14 zebrafish, were infected with 106 colony forming units (CFU) of wild-type or MR14 via cloaca injection. Zebrafish survival was monitored every 6 h for 24 h. The control group represents zebrafish injected with PBS. **** p < 0.0001, ** p < 0.01.