REFINED CRYSTAL-STRUCTURE OF LIVER ALCOHOL-DEHYDROGENASE NADH COMPLEX AT 1.8-ANGSTROM RESOLUTION

The crystal structure of the ternary complex of horse liver alcohol dehydrogenase (LADH) with the co-enzyme NADH and inhibitor dimethyl sulfoxide (DMSO) has been refined by simulated annealing with molecular dynamics and restrained positional refinement using the program X-PLOR. The two subunits of the enzyme were refined independently. The space group was P1 with cell dimensions a = 51.8, b = 44.5, c = 94.6 Angstrom, alpha = 104.8, beta = 102.3 and gamma = 70.6 degrees. The resulting crystallographic R factor is 17.3% for 62440 unique reflections in the resolution range 10.0-1.8 Angstrom. A total of 472 ordered solvent molecules were localized in the structure. An analysis of secondary-structure elements, solvent content and NADH binding is presented.