Crystallization and preliminary X-ray analysis of methylthioribose-1-phosphate isomerase from Bacillus subtilis

Methylthioribose-1-phosphate isomerase (MtnA) from Bacillus subtilis, the first enzyme in the downstream section of the methionine-salvage pathway, was crystallized using the sitting-drop vapour-diffusion method. Crystals grew using ammonium sulfate as the precipitant at 293 K. They diffracted to 2.5 Å at 100 K using synchrotron radiation and were found to belong to the tetragonal space group P4₁, with unit-cell parameters a = b = 69.2, c = 154.7 Å. The asymmetric unit contains two molecules of MtnA, with a V_M value of 2.4 Å³ Da^-1 and a solvent content of 48%.