Figure 6
The S. suis serotype 9 (S9) AgI/II, but not that of serotype 2 (S2), is involved in protection against acid stress. Effect of acid stress on S. suis S2 and S9 viability, determined at pH 3 (A, B) and pH 5 (C, D). Data represent the mean ± SEM from at least three independent experiments. *(p < 0.05) indicates a significant difference between the S. suis S9 wild-type or complemented strain (S9CΔagI/II) and agI/II-deficient mutant (S9ΔagI/II).