CRYSTAL-STRUCTURE OF THE COMPLEX OF TRICHOSANTHIN WITH NADPH AT 0.172NM RESOLUTION

The orthorhombic crystal structure of the complex of trichosanthin wit h nicotinamide adenine dinucleotide phosphate has been determined by m olecular replacement method using one of the molecules of the monoclin ic crystal structure of trichosanthin at 0.27 nm resolution as the sea rch model. The crystallographic refinement at 0.172 nm resolution led to a final R-factor of 17.4% with root-mean-square deviations of 0.001 3 nm and 3.8 degrees from the ideal bond lengths and bond angles, resp ectively. The quality of the structure, the polypeptide chain fold and the comparison of it with that of the monoclinic trichosanthin struct ure, the location of nicotinamide adenine dinucleotide phosphate, the active site structure as well as the solvent structure are described.