Expression, purification, crystallization and preliminary X-ray analysis of ribitol-5-phosphate cytidylyltransferase from Bacillus subtilis.

TarI is a ribitol-5-phosphate cytidylyltransferase that catalyzes the formation of CDP-ribitol, which is involved in the biosynthesis of wall teichoic acids, from CTP and ribitol 5-phosphate. TarI from Bacillus subtilis (BsTarI) was purified and crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 1.78 Å and belonged to the monoclinic space group C2, with unit-cell parameters a = 103.74, b = 60.97, c = 91.80 Å, β = 113.48°. The initial structural model indicated that the crystals of BsTarI contained a dimer in the asymmetric unit.