FIG. 3.

Expression of PEK in E. coli as measured by immunoblotting. PEK or PEK-Δ785-1108 fused to amino-terminal polyhistidine tags was expressed in E. coli by using the T7 promoter system, as described in Materials and Methods. Equal amounts of total cell lysates were analyzed by SDS-PAGE, and PEK was detected by immunoblotting with a polyclonal antibody that recognizes the polyhistidine sequences. Vector, lysates prepared from E. coli containing only the parent vector, pET28a. Molecular weight markers, in kilodaltons, are on the left.