5.1.3.31 ? x * 29800, recombinant His-tagged enzyme, SDS-PAGE -, 749220 5.1.3.31 dimer - 728140 5.1.3.31 dimer 2 * 32000, SDS-PAGE 727219 5.1.3.31 dimer 2 * 33000, SDS-PAGE -, 727188 5.1.3.31 homodimer - 726603 5.1.3.31 homodimer 2 x 30000, recombinant enzyme, SDS-PAGE -, 746648 5.1.3.31 additional information the asymmetric unit contained two homologous subunits, and the dimer is generated by twofold symmetry. In MJ1311p, Glu125, Leu126 and Trp127 from one subunit are located over the metal-ion-binding site of the other subunit and contribute to the active site, narrowing the substrate-binding cleft. Three-dimensional structural analysis of MJ1311p, overview. The enzyme MJ1311p monomer is folded into an (alpha/beta)8 barrel carrying four additional helical segments, alpha1', alpha2', alpha4', and alpha6', which are inserted before alpha1, alpha2, alpha4, and alpha6, respectively. The quaternary-structural arrangement of MJ1311p is notably different from those of D-TE family enzymes -, 746648