FIG. 3.

Point mutations in the N terminus of DifA influence EPS production. (A) DifA protein levels by immunoblot analysis. Four micrograms of whole-cell lysates from each strain was analyzed by SDS-PAGE and probed with polyclonal anti-DifA antibodies. (B) DifA membrane localization. The membrane (M) and the soluble (S) fractions normalized to whole-cell lysates were analyzed by immunoblotting as in panel A. (C) EPS production of the point mutants was examined as described for Fig. 1C. Strains: difA⁺, YZ619; ΔdifA, YZ601; L38P, YZ1822; G45A, YZ1820; Y46C, YZ1821; and P96L, YZ1823.