Overexpression, purification, crystallization and preliminary X-ray crystallographic analysis ofPseudomonas aeruginosaL-arginine deiminase

Pseudomonas aeruginosa L-arginine deiminase, an enzyme catalyzing the irreversible catabolism of arginine to citrulline, has been produced in selenomethionyl form. The protein was purified and crystallized by the sitting-drop vapour-diffusion method using a precipitant solution consisting of 55% MPD, 100 mM cacodylate pH 6.5, 20 mM MgCl(2). Crystals display tetragonal symmetry (P4(1)2(1)2 or P4(3)2(1)2), with unit-cell parameters a = b = 106.0, c = 300.2 A, and diffract to 2.7 A resolution. A complete MAD data set was collected to 3.2 A resolution on beamline BM30 at ESRF.