Fig. 2.

Immunoblot analysis of CtxA production. Expression of CtxA was examined by immunoblot using anticholera toxin. Approximately 5 × 10⁷ cells were loaded onto each lane. Lanes 1 and 2: O395; lanes 3 and 4: MG116025; lanes 5 and 6: MG116025-toxT^F139Y; lanes 7 and 8: IB4122; lanes 9 and 10: IB4122-toxT^Y139F; lanes 11 and 12: A213; and lanes 13 and 14: A213-toxT^Y139F. Odd-numbered lanes are bacterial samples grown at 37 °C in LB media, and even-numbered lanes are bacterial samples grown at 30 °C in LB, pH 6.5. Arrow indicates CtxA.