Preliminary X-ray crystallographic analysis of tRNA pseudouridine 55 synthase from the thermophilic eubacterium Thermotoga maritima

Thermotoga maritima TruB, an enzyme responsible for the formation of pseudouridine in tRNA, has been purified and crystallized by the hanging-drop vapour-diffusion method in 100 mM citrate pH 3.5, 200 mM Li₂SO₄, 20% glycerol, 13% PEG 8000. Crystals display orthorhombic symmetry, with unit-cell parameters a = 47.39, b = 83.88, c = 98.72 Å, and diffract to 2.0 Å resolution using synchrotron radiation. A solution was obtained by molecular replacement using part of the recently published crystal structure of Escherichia coli TruB bound to a synthetic RNA.