| DATA WERE COLLECTED AT PH 6.4 AND AT 25 DEGREES CELSIUS. RESTRAINTS USED FOR THE STRUCTURE CALCULATIONS INCLUDED 547 NOE RESTRAINTS CONSISTING OF 108 INTRA-RESIDUE, 175 SEQUENTIAL, 91 MEDIUM (1<|I-J|<6) AND 173 LONG RANGE NOES. ADDITIONALLY, 50 HYDROGEN BONDING DISTANCES AS WELL AS DIHEDRAL ANGLE RESTRAINTS FOR 69 PHI ANGLES AND 8 CHI-1 ANGLES WERE INCLUDED. STEREOSPECIFIC ASSIGNMENTS HAVE BEEN MADE FOR THE METHYLENE PROTONS OF ASN 22, CYS 42, ASN 51, SER 53, PHE 54 AND TYR 55. STEREOSPECIFIC ASSIGNMENTS HAVE ALSO BEEN MADE FOR THE METHYL GROUPS OF VAL 16, LEU 17, VAL 28, LEU 48, VAL 52, LEU 62, AND LEU 84. THIS STUDY AND REFERENCE 1 ABOVE SHOW THAT CYS 38, CYS 42, CYS 69, AND CYS 72 ARE THE LIGANDS FOR A TIGHTLY BOUND ZINC ION. A 2.3 ANGSTROM THIOL - ZINC DISTANCE RESTRAINT WAS IMPOSED ON THE FOUR CYSTEINE METAL LIGANDS. ADDITIONAL DISTANCE AND DIHEDRAL RESTRAINTS WERE APPLIED TO ENFORCE A TETRAHEDRAL METAL LIGATION AND TO MAINTAIN PROPER SP3 HYBRIDIZATION GEOMETRIES OF THE COORDINATED SULFUR ATOMS. A DIHEDRAL ANGLE RESTRAINT MAINTAINS AN S TYPE LIGAND CONFIGURATION. | DGII |
