Crystallization and preliminary X-ray characterization of an NAD(P)-dependent butanol dehydrogenase A from Geobacillus thermodenitrificans NG80-2

Geobacillus thermodenitrificans NG80-2 encodes two long-chain NAD(P)-dependent alcohol dehydrogenases, gtADH1 and gtADH2, in the terminal oxidation pathway of long-chain n-alkanes for the conversion of long-chain alkyl alcohols to their corresponding aldehydes. Both gtADH1 and gtADH2 are thermostable enzymes and oxidize long-chain alkyl alcohols up to at least C₃₀. In order to understand the structural basis for their role in long-chain alkane degradation, we have crystallized gtADH2. Single, colourless crystals were obtained from a recombinant preparation of ADH2 overexpressed in Escherichia coli. The crystals belong to space group C222₁, with unit-cell parameters a = 56.0, b = 99.6, c = 123.1 Å. Diffraction data were collected in-house to 1.79 Å resolution. The crystals contain one monomer in the asymmetric unit, with a V_M value of 2.17 Å³ Da^-1 and an estimated solvent content of 43%.