Fig. 4

Optimization of the CshA binding on Lm. fermentum cells. Pretreatment of the Lm. fermentum cells affected the surface binding of CshA (A). NaCl concentration (B) and pH (C), as well as the binding time and temperature (D) also influenced the surface binding of CshA. The binding capacity of pretreated Lm. fermentum cells was determined by fitting the fluorescence at different protein concentration into a nonlinear curve (E), then calculated using a standard curve (F). All experiments were done in triplicates and reported as mean ± SD. Significant differences were determined using ANOVA with Tukey’s test for pairwise comparison of means. Differences are denoted by ** P < 0.01 and *** P < 0.001, or by different letters