CRYSTALLIZATION AND PRELIMINARY-X-RAY ANALYSIS OF ALDEHYDE DEHYDROGENASE FROM VIBRIO-HARVEYI

Aldehyde dehydrogenase from Vibrio harveyi catalyzes the oxidation of long-chain aliphatic aldehydes to acids. The enzyme is unique among th e family of aldehyde dehydrogenases in that it exhibits much higher sp ecificity for the cofactor NADP(+) than for NAD(+). The sequence of th is form of the enzyme varies significantly from the NAD(+) dependent f orms, suggesting differences in the three-dimensional structure that m ay be correlated to cofactor specificity. Crystals of the enzyme have been, grown both in the presence and absence of NADP(+) using the hang ing drop vapor diffusion technique. In order to improve crystal size a nd quality, iterative seeding techniques were employed. The crystals b elong to space group P2(1), with unit cell dimensions a = 79.4 Angstro m, b = 131.1 Angstrom, c = 92.2 Angstrom, and beta = 92.4 degrees. Fre ezing the crystal to 100K has enabled a complete set of data to be col lected using a rotating anode source (lambda = 1.5418 Angstrom). The c rystals diffract to a minimum d-spacing of 2.6 Angstrom, resolution. B ased on density calculations, two homodimers of molecular weight 110 k Da are estimated to be present in the asymmetric unit. Self-rotation f unctions show the presence of 3 noncrystallographic twofold symmetry a xes.