Pyrrolysine—tRNAPyl ligase explained

Pyrrolysine—tRNA^Pyl ligase
Ec Number:	6.1.1.26

Pyrrolysine—tRNA^Pyl ligase (PylS, pyrrolysyl-tRNA synthetase) is an enzyme with systematic name L-pyrrolysine:tRNAPyl ligase (AMP-forming).^{[1] [2] [3]} This enzyme catalyses the following chemical reaction

ATP + L-pyrrolysine + tRNAPyl

\rightleftharpoons AMP + diphosphate + L-pyrrolysyl-tRNAPyl

This enzyme is specific for pyrrolysine as substrate as it cannot be replaced by lysine or any of the other natural amino acids.

Notes and References

1. Blight SK, Larue RC, Mahapatra A, Longstaff DG, Chang E, Zhao G, Kang PT, Green-Church KB, Chan MK, Krzycki JA . Direct charging of tRNA(CUA) with pyrrolysine in vitro and in vivo . Nature . 431 . 7006 . 333–5 . September 2004 . 15329732 . 10.1038/nature02895 . 4395541 .
2. Polycarpo C, Ambrogelly A, Bérubé A, Winbush SM, McCloskey JA, Crain PF, Wood JL, Söll D . An aminoacyl-tRNA synthetase that specifically activates pyrrolysine . Proceedings of the National Academy of Sciences of the United States of America . 101 . 34 . 12450–4 . August 2004 . 15314242 . 515082 . 10.1073/pnas.0405362101 . free .
3. Schimmel P, Beebe K . Molecular biology: genetic code seizes pyrrolysine . Nature . 431 . 7006 . 257–8 . September 2004 . 15372017 . 10.1038/431257a . free .