Crystallization and preliminary X-ray diffraction crystallographic study of tRNA m¹A58 methyltransferase from Saccharomyces cerevisiae

In Saccharomyces cerevisiae, TRM6 and TRM61 compose a tRNA methyltrans­ferase which catalyzes the methylation of the N1 of adenine at position 58 in tRNAs, especially initiator methionine tRNA. TRM61 is the subunit that binds S-­adenosyl-L-methionine and both subunits contribute to target tRNA binding. In order to elucidate the catalytic mechanism of TRM6-TRM61 and the mode of interaction between the two subunits, expression, purification, crystallization and X-­ray diffraction analysis of the TRM6-TRM61 complex were performed in this study. The crystals diffracted to 2.80 Å resolution and belonged to the trigonal space group P3₁21 or P3₂21, with unit-cell parameters a = b = 139.14, c = 101.62 Å.