FIGURE 2: Known and hypothetical advantages of Aux3 acquisition by V. cholerae. (Left) Environmental V. cholerae laterally acquires Aux3. Light blue curved cells = Aux3(−) V. cholerae. Green curved cells = Aux3 (+) V. cholerae. (Middle) Aux3(+) V. cholerae kills Aeromonas (red cells) and Edwardsiella (dark blue cells). (Right) If Aux3-dependent killing is important for colonization a specific niche such as the fish gut, then passage through that niche may induce physiological changes important for pathogenesis such as hypermotility or aggregate formation.