Crystallization and preliminary crystallographic analysis of galactose-1-phosphate uridylyltransferase from Escherichia coli

Galactose-1-phosphate uridylyltransferase catalyzes the formation of UDP-galactose during normal cellular metabolism, making it an essential enzyme in all cells. The enzyme from Escherichia coli has been crystallized at pH 5.9 in the presence of phenyl-UDP (P¹-5'-uridyl-P²-phenyl diphosphate), a substrate analog, using PEG 10 000 in combination with Li₂SO₄ and NaCl. Crystals belong to space group P2₁2₁2 with unit-cell dimensions a = 58.6, b = 217.6 and c = 69.6 Å. There is one dimer or two subunits in the asymmetric unit. Crystals are relatively insensitive to X-ray radiation and diffract beyond 2.5 Å resolution. A low-resolution native data set has been recorded.