Intracellular solubility analysis of wt and mutated Peb1 proteins. The top panels show SDS-PAGE analysis of Peb1 expression in whole bacterial cells of MKS12 carrying the plasmids indicated above the panels. Cells were lysed and the cytoplasmic content was fractionated by ultracentrifugation as explained in methods section. Samples correspond to 100 μl of culture (top panel). The lower panels show Western blot analysis with anti-Peb1 antibodies of samples from the insoluble and soluble fractions. Samples correspond to 30 μl of culture. Plasmid pLA25 encoded wt Peb1, see Fig. 3 and Table 1 for details regarding the other plasmids. Molecular weight markers in kDa are indicated on the left. The letter E indicates expression, IF insoluble fraction, and SF soluble fraction.