TWO SUBUNITS OF FUMARASE C ARE PRESENT IN THE ASU. THE MOLECULE IS A TETRAMER AND TRANSFORMATION MATRIX/VECTOR FOR GENERATING THE OTHER 2 SUBUNITS IS GIVEN. IN ONE SUBUNIT RESIDUES 317 - 320 ARE MISSING DUE TO A BREAK IN THE ELECTRON DENSITY. ALTHOUGH THIS IS A RECOMBINANT PROTEIN WITH A FIVE HISTIDINE ARM ON THE C-TERMINAL, NO ELECTRON DENSITY WAS SEEN TO ACCOUNT FOR THESE RESIDUES. THE CRYSTALLINE PROTEIN INCLUDES COORDINATES FOR A MALATE AND PYROMELLITIC ACID OBSERVED IN THE ELECTRON DENSITY AND DESCRIBED FULLY IN THE BIOCHEMISTRY REFERENCE.
RESIDUES IN AND AROUND THR 96, HIS 129, SER 139, HIS 188, THR 230, LYS 324, AND LEU 358 ARE ALL ...RESIDUES IN AND AROUND THR 96, HIS 129, SER 139, HIS 188, THR 230, LYS 324, AND LEU 358 ARE ALL INVOLVED IN CONTACTS DIRECTLY OR INDIRECTLY WITH EITHER LIGAND AT EITHER THE ACTIVE SITE OR B-SITE.