Fig 1.

Complementation capacity of C. jejuni NCTC11168 nhaA1 and nhaA2 genes in a TSP, alkali, and Na⁺-sensitive E. coli cation/proton antiporter mutant. The E. coli strains tested were wt (CTN39, ♦), cation/antiporter ΔnhaA ΔnhaB ΔchaA mutant (CTN40, ■), cation/antiporter ΔnhaA ΔnhaB ΔchaA mutant containing plasmid pCTN1 with the C. jejuni NCTC11168 nhaA1 and nhaA2 genes (CTN58, □), and cation/antiporter ΔnhaA ΔnhaB ΔchaA mutant containing negative control vector pET-21(+) (CTN15, ▲). The E. coli strains were grown in LB(K) medium containing 0.2% TSP (A), pH 8.5 adjusted with KOH (B), or 0.2 M NaCl (C) for up to 360 min at 37°C. One representative of four experiments under each condition is presented, and similar results were obtained in all four experiments.