Purification, crystallization and preliminary X-ray crystallographic study of the tRNA pseudouridine synthase TruB from Streptococcus pneumoniae

The RNA pseudouridine synthase TruB catalyses the isomerization of uridine to pseudouridine (Ψ) at residue 55 of elongator tRNAs. In order to better elucidate the functions of TruB in the formation of pseudouridine, the three-dimensional structure of full-length TruB was determined by X-ray crystallography. Here, the expression, purification, crystallization and preliminary crystallographic analysis of TruB from Streptococcus pneumoniae are reported. The crystal belonged to space group P2, with unit-cell parameters a = 37.65, b = 78.09, c = 56.33 Å, β = 102.05°, and diffracted to a resolution of 1.7 Å. The crystal is most likely to contain one molecule in the asymmetric unit, with a V_M value of 2.40 ų Da⁻¹.