Crystal structure of an Escherichia coli tRNAGly microhelix at 2.0 Å resolution

tRNA identity elements determine the correct aminoacylation by the cognate aminoacyl-tRNA synthetase. In class II aminoacyl tRNA synthetase systems, tRNA specificity is assured by rather few and simple recognition elements, mostly located in the acceptor stem of the tRNA. Here we present the crystal structure of an Escherichia coli tRNAGly aminoacyl stem microhelix at 2.0 Å resolution. The tRNAGly microhelix crystallizes in the space group P3221 with the cell constants a = b = 35.35 Å, c = 130.82 Å, γ = 120°. The helical parameters, solvent molecules and a potential magnesium binding site are discussed.