The crystal structure of the ternary complex of horse liver alcohol de
hydrogenase (LADH) with the co-enzyme NADH and inhibitor dimethyl sulf
oxide (DMSO) has been refined by simulated annealing with molecular dy
namics and restrained positional refinement using the program X-PLOR.
The two subunits of the enzyme were refined independently. The space g
roup 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 mo
lecules were localized in the structure. An analysis of secondary-stru
cture elements, solvent content and NADH binding is presented.