Expression, purification, crystallization and preliminary X-ray analysis of two arginine-biosynthetic enzymes from Mycobacterium tuberculosis

The gene products of two open reading frames from Mycobacterium tuberculosis (Mtb) have been crystallized using the sitting-drop vapour-diffusion method. Rv1652 encodes a putative N-acetyl-γ-glutamyl-phosphate reductase (MtbAGPR), while the Rv1656 gene product is annotated as ornithine carbamoyltransferase (MtbOTC). Both MtbAGPR and MtbOTC were expressed in Escherichia coli, purified to homogeneity and crystallized. Native data for each crystal were collected to resolutions of 2.15 and 2.80 Å, respectively. Preliminary X-ray data are presented for both enzymes.