Peripheral "insertion motif" away from the catalytic sites modulates the editing activity of leucyl-tRNA synthetase

【摘要】：正CPl(connective polypeptide 1) is a long insertion to the aminoacylation catalytic domain of the subclass Ia aminoacyl-tRNA synthetases(aaRS) including leucyl-, isoleucyl-,and valyl-tRNA synthetase(LeuRS,IleRS and ValRS respectively).The function of CPl was identified as a post-transfer hydrolytic editing domain in the three aaRSs, however,in most known LeuRS,isolated CPl cannot act as an editing active protein except two isolated CP1 domains, of which one is from the LeuRS of a deep-rooted bacterium Aquifex aeolicus(Aa- LeuRS) and the another is from the