Engineering a ribozyme with aminoacyl-tRNA synthetase activity

A ribozyme that can charge a tRNA with amino acids and discriminate between cognate and non-cognate tRNAs is of interest because an RNA with this ability may have been a critical for translation in the transition from the RNA world. In addition, it could provide a tool for incorporating non-canonical amino acids for biotechnology applications. Here, we rationally engineer a ribozyme by fusing a tRNA binding module derived from a T-box riboswitch with a catalytic module (a flexizyme) to generate a ribozyme that can amino acylate a target tRNA. We demonstrate that this ribozyme be readily redesigned to alter tRNA specificity. This ribozyme is compatible with an in vitro translation system and could be used to recode a protein sequence to site-specifically incorporate a non-canonical amino acid.