SDS-PAGE gel with recombinant maize Trxs and commercial E. coli Trx. About 7 μg of each recombinant protein was applied per lane. Lane 1, ZmTrx f1; lane 2, ZmTrx f2; lane 3, ZmTrx m1; lane 4, ZmTrx m2; lane 5, ZmTrx m5; lane 6, ZmTrx x; lane 7, EcoTrx; lane M, size markers.