Preliminary X-ray crystallographic analysis of ornithine acetyltransferase (Rv1653) from Mycobacterium tuberculosis.

The gene product of open reading frame Rv1653 from Mycobacterium tuberculosis is annotated as encoding a probable ornithine acetyltransferase (OATase; EC 2.3.1.35), an enzyme that catalyzes two steps in the arginine-biosynthesis pathway. It transfers an acetyl group from N-acetylornithine to L-glutamate to produce N-acetylglutamate and L-ornithine. Rv1653 was crystallized using the sitting-drop vapour-diffusion method. The native crystals diffracted to a resolution of 1.7 A and belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 60.1, b = 99.7, c = 155.3 A. The preliminary X-ray study showed the presence of a dimer in the asymmetric unit of the crystals, which had a Matthews coefficient V(M) of 2.8 A(3) Da(-1).