Expression, crystallization and preliminary X-ray crystallographic analysis of aldehyde dehydrogenase (ALDH) from Bacillus cereus

Aldehyde dehydrogenase (ALDH) catalyses the oxidation of aldehydes using NAD(P)⁺ as a cofactor. Most aldehydes are toxic at low levels. ALDHs are used to regulate metabolic intermediate aldehydes. The aldh gene from Bacillus cereus was cloned and the ALDH protein was expressed, purified and crystallized. A crystal of the ALDH protein diffracted to 2.6 Å resolution and belonged to the monoclinic space group P2₁, with unit-cell parameters a = 83.5, b = 93.3, c = 145.5 Å, β = 98.05°. Four protomers were present in the asymmetric unit, with a corresponding V_M of 2.55 ų Da⁻¹ and a solvent content of 51.8%.