Crystallization and preliminary X-ray diffraction studies of the cobalamin-binding domain of methionine synthase from Escherichia coli.

Crystals of a cobalamin-binding domain (M(r) = 28,000) have been grown in polyethylene glycol 6000 at pH 7.5, starting from solutions of intact (M(r) = 133,000) cobalamin-dependent methionine synthase. The crystals are orthorhombic in space group P2(1)2(1)2(1), with cell dimensions a = 96.9 A, b = 55.4 A, c = 103.8 A. For two molecules per asymmetric unit, the calculated VM value is 2.45 A3/Da. A native data set has been collected to 3 A resolution.