Crystal structure of Nanoarchaeum equitans tyrosyl-tRNA synthetase and its aminoacylation activity toward tRNA with an extra guanosine residue at the 5'-terminus.

tRNA of Nanoarchaeum equitans has a remarkable feature with an extra guanosine residue at the 5'-terminus. However, the N. equitans tRNA mutant without extra guanosine at the 5'-end was tyrosylated by tyrosyl-tRNA synthase (TyrRS).