Crystallization and preliminary X-ray analysis of an NAD⁺-dependent alcohol dehydrogenase from the extreme thermophilic archaebacterium Sulfolobus solfataricus

An NAD⁺-dependent alcohol dehydrogenase from the extreme thermophilic archaebacterium Sulfolobus solfataricus has been crystallized in the holo-enzyme and apo-enzyme forms. Crystals of the holo-enzyme grow from 2-methyl-2,4-pentanediol at pH 8.4 with the addition of NADH and at pH 7.0 with the addition of NADH and dimethyl sulphoxide. Crystals of the apo-enzyme grow at pH 6.3 from a mixture of polyethylene glycol 4000 and propan-2-ol. The holo-enzyme crystallizes in C2 with a dimer in the asymmetric unit, however the crystals are twinned and unsuitable for data collection. The apo-enzyme crystallizes in I4₁22 (a =126.82 Å, b = 118.95 Å) with a monomer in the asymmetric unit, and the single crystals diffract to 2.8 Å.