Crystallization and preliminary X-ray analysis of pyridoxal 4-dehydrogenase, the second enzyme in degradation pathway I of pyridoxine.

Pyridoxal 4-dehydrogenase (PLDH; EC L1.107) is the second enzyme in the bacterial degradation pathway I of vitamin B6, which catalyzes the oxidation of pyridoxal to 4-pyridoxolactone using NAD+. PLDH from Microbacterium luteolum, a dimeric protein with a subunit molecular weight of 38 kDa, was crystallized at 277 K in a drop solution comprising 15%(w/v) polyethylene glycol 4000, 0.15 M sodium acetate, 7.5 mM n-octyl-β-D-glucoside and 0.075 M Tris-HCl pH 7.5 by the sitting-drop vapour-diffusion method. The crystals were monoclinic and belonged to space group C2, with unit-cell parameters a = 107.0, h = 56.7, c = 130.2 Å, β = 103.6°. Diffraction data were collected from a single crystal to 2.0 Å. [ABSTRACT FROM AUTHOR]