| CONJOINED RIGID BODY AND TORSION ANGLE SIMULATED ANNEALING | THE STRUCTURE OF THE COMPLEX WAS SOLVED BY CONJOINED RIGID BODY/TORSION ANGLE SIMULATED ANNEALING USING XPLOR-NIH. THE CALCULATIONS ARE BASED ON 40 INTERMOLECULAR INTERPROTON DISTANCE RESTRAINTS, 78 INTRAMOLECULAR INTERPROTON DISTANCE RESTRAINTS RELATED ONLY TO THE ACTIVE SITE LOOP OF IIBCHB, 82 TORSION ANGLE RESTRAINTS RELATED TO THE BACKBONE OF THE ACTIVE SITE LOOP OF IIBCHB (RESIDUES 9-16, CHAIN D) AND THE INTERFACIAL SIDE CHAINS, 153 DIPOLAR COUPLINGS RELATED TO IIBCHB, AND 15 13CALPHA/13CBETA CHEMICAL SHIFT RESTRAINTS RELATED TO THE ACTIVE SITE LOOP OF IIBCHB. WITH THE EXCEPTION OF THE ACTIVE SITE LOOP OF IIBCHB (RESIDUES 9-16 OF CHAIN D) AND A MOBILE LOOP OF IIACHB (RESIDUES 62-71 OF CHAINS A, B, C) THE BACKBONE OF THE TWO PROTEINS AND NON-INTERFACIAL SIDE CHAINS ARE TREATED AS RIGID BODIES WITH ROTATIONAL AND TRANSLATIONAL DEGREES OF FREEDOM. THE COORDINATES FOR THE PORTIONS TREATED AS RIGID BODIES ARE TAKEN FROM THE X-RAY STRUCTURE OF IIBCHB (PDB CODE 1IIB) AND THE NMR STRUCTURE OF IIACHB (PDB CODE 1WCR). THE BACKBONE OF RESIDUES 9-16 OF CHAIN D, 62-71 OF CHAINS A, B AND C, AND THE INTERFACIAL SIDE CHAINS ARE GIVEN FULL TORSIONAL DEGREES OF FREEDOM. THE TARGET FUNCTION COMPRISES NOE-DERIVED INTERPROTON DISTANCE RESTRAINTS, TORSION ANGLE RESTRAINTS, RDC RESTRAINTS, 13CALPHA/13CBETA CHEMICAL SHIFT RESTRAINTS, A QUARTIC VAN DER WAALS REPULSION TERM FOR THE NON-BONDED CONTACTS, A MULTIDIMENSIONAL TORSION ANGLE DATABASE POTENTIAL OF MEAN FORCE, AND A GYRATION VOLUME POTENTIAL TO ENSURE OPTIMAL PACKING. FURTHER DETAILS ARE GIVEN IN THE ASSOCIATED PUBLICATION. | Xplor-NIH |
