Immunoblot analysis after native PAGE and activity staining of recombinant rat SMP30. Samples were electrophoresed on a native polyacrylamide gel, and the proteins on the gel were electroblotted onto a membrane. Detection of specific proteins was carried out with anti-MBP antibody (A), anti-rat SMP30 antibody (B), and activity staining (C). To stain for enzyme activity, d-galactono-γ-lactone was used as substrate. Lane 1, the lysate of E. coli cells expressing a fusion of MBP with β-gal α-fragment (control); lane 2, the lysate of E. coli cells expressing a fusion of MBP with rat SMP30. The arrow shows the position of a fusion of MBP with rat SMP30.