Comparative densitometric analysis of pH and calcium-dependent Yops secretion in Y. pseudotuberculosis.

To compare and quantify the Yop secretion efficiency in wild-type Y. pseudotuberculosis under different conditions, Coomassie stained Yop secretion profiles were subjected to densitometric analysis with Multi Gauge software (Fuji Film). The protein YopJ (boxed in Figure 4 and Figure 5E) was selected for quantitative analysis. Growth kinetics in media with different pH’s (Figure S4B) showed attenuation of bacterial growth directly linked to the observed Yop secretion efficiency.

secretion efficiency was set to 100%;

secretion efficiency at pH 7.5 was set to 100%.