[Fusion and expression of the gene encoding human Mn-SOD to anti-CEA single-chain antibody in Escherichia coli]

The gene encoding human manganese-superoxide dismutase (Mn-SOD) was fused to anti-carcinoembryonic antigen single-chain antibody gene to construct the fusion gene, then was ligated into prokaryotic expression vector pET-22b(+), The fusion gene was expressed in E. coli at high level, accounting for 24% of the total bacteria soluble protein; and was characterized by SDS-PAGE and Western-blot analysis; the expression product had the CEA-binding ability in RIA, and also had the SOD activity by pyrogallol autoxidation assay. So, the Mn-SOD moiety retains substantial enzymatic activity, where the ScFv moiety can deliver the fusion protein to tumor, Mn-SOD is a potential tumor-suppressor gene, maybe the fusion protein can provide a new pathway to tumor therapy.