Atomic Group 'Mutagenesis' Reveals Major Groove Fine Interactions of a tRNA Synthetase with an RNA Helix

摘要

RNA discrimination by aminoacy-tRNA synthetases involves both major and minor groove interactions with the acceptor stem domain of tRNA substrates. In the case of class Ⅱ Escherichia coli alanyl-tRNA synthetase (AlaRS), minor groove atomic groups in and around the unique G3:U70 base pair previously have been shown to be critical for recognition. In this work, we probe the role of the first (1:72) base pair in discrimination by AlaRS by incorporating 26 new base pair combinations at this site.