FIGURE 1.

Recombinant PgDps protein exists in solution as a dodecamer. A, purified recombinant PgDps with or without affinity Strep-tag II appears as a monomer on denaturing SDS-polyacrylamide gel. Lane 1, molecular mass markers; lane 2, E. coli lysate; lane 3, purified tagged PgDps; lane 4, de-tagged PgDps. B, molecular mass determination of PgDps by SEC-MALLS. The elution profile is shown as the blue line. The red line superimposed on the main elution peak indicates the molecular weight distribution of the protein. The experimental molecular mass for PgDps is 224 kDa with a polydispersity index of 1.001 ± 0.021, consistent with a dodecameric complex.