MW: 57.9kDa (521aa), confirmed by MALDI-TOF. Purity >90% by SDS-PAGE. SEPSECS, also known as SLA/LP autoantigen, catalyzes the final step of sec synthesis by converting O-phosphoseryl-tRNA (sec) to selenocysteinyl-tRNA (sec) using selenophosphate as the selenium donor. Also, this protein is considered a specific marker of autoimmune hepatitis. Recombinant human SEPSECS protein, fused to His-tag at N-terminus, was expressed in E Coli and purified by using conventional chromatography techniques.