MSRB3His protein.MSRB3 is His-tagged at the N-terminal.MSRB3 (Methionine-R-sulfoxide reductase, EC1.8.4.6;accession number AAH40053) is one of three differentmammalian MSRB enzymes. It carries out the reduction ofmethionine-R-sulfoxide to methionine. Human studies haveshown the highest levels of expression in smooth muscletissues. Its proposed function is the repair of oxidativedamage to proteins to restore biological activity. Purity >90% by SDS-PAGE