wwPDB validation report of PDB entry 1BCF

EACH SUBUNIT INCLUDES A BINUCLEAR METAL-BINDING SITE INVOLVING RESIDUES GLU 18, GLU 51, HIS 54, GLU 94, GLU 127, AND HIS 130 AND LINKING TOGETHER THE FOUR MAJOR HELICES (A, B, C, AND D) OF THE SUBUNIT. THE IDENTITY OF THE METAL IONS HAS NOT BEEN DETERMINED. THEY ARE LISTED BELOW AS DIVALENT MANGANESE (RESIDUES *A* 600, *A* 601, *B* 600, AND *B* 601) AND ARE NAMED SITES MA1, MA2, MB1, AND MB2.
THE HEME MOIETY IS BOUND SYMMETRICALLY TO SUBUNITS *A* AND *B* BY BONDS FROM THE HEME IRON TO THE SULFUR ATOMS OF MET *A* 52 AND MET *B* 52.

THE STRUCTURE OF A UNIQUE, TWO-FOLD SYMMETRIC, HAEM-BINDING SITE

THE BACTERIOFERRITIN MOLECULE IS A HOLLOW SHELL OF APPROXIMATE 432 SYMMETRY COMPOSED OF 24 IDENTICAL PROTEIN CHAINS AND 12 HEME GROUPS. THE BUILDING BLOCK FOR THE SHELL IS A PROTEIN DIMER HOLDING THE HEME MOIETY WITH ITS QUASI-DYAD AXIS CLOSELY ALIGNED WITH THE PSEUDO-DYAD OF THE DIMER. A COMPLETE SHELL CAN BE CONSTRUCTED FROM THE COORDINATES GIVEN BELOW FOR PROTEIN SUBUNITS *A* AND *B* AND THE HEME PROSTHETIC GROUP *HEM* BY FIRST APPLYING EACH OF THE FIVE NON-CRYSTALLOGRAPHIC SYMMETRY MATRICES GIVEN BELOW (MTRIX1...MTRIX5) TO OBTAIN ONE ASYMMETRIC UNIT CONSISTING OF ONE HALF OF THE SHELL AND THEN APPLYING THE CRYSTALLOGRAPHIC TWO-FOLD ROTATION (Y, X, -Z) TO THIS.

20191225.v01 (using entries in the PDB archive December 25th 2019)
geometric validation package for ligand chemistry in protein x-ray structures