Cubic crystals of phosphopantetheine adenylyltransferase from Escherichia coli

Phosphopantetheine adenylyltransferase (PPAT, E.C. 2.7.7.3) catalyzes the penultimate step in coenzyme A (CoA) biosynthesis, transferring an adenylyl group from ATP to 4′-phosphopantetheine, and forming dephospho-CoA. Cubic crystals of native PPAT from Escherichia coli as well as PPAT in complex with its substrates were obtained. The crystals belong to space group I23 or I2₁3 with unit-cell dimension a = 135.5 Å. The crystals diffract to better than 1.8 Å resolution on a Cu Kα rotating-anode generator. The asymmetric unit is likely to contain two molecules, corresponding to a packing density of 2.9 ų Da⁻¹.