1OBC

LEUCYL-TRNA SYNTHETASE FROM THERMUS THERMOPHILUS COMPLEXED WITH A POST-TRANSFER EDITING SUBSTRATE ANALOGUE

Summary for 1OBC

• Entry DOI: 10.2210/pdb1obc/pdb
• Related: 1H3N 1OBH
• Descriptor: LEUCYL-TRNA SYNTHETASE, LEUCINE, ZINC ION, ... (7 entities in total)
• Functional Keywords: aminoacyl-trna synthetase, class i aminoacyl-trna synthetase, atp + l-leucine + trna (leu) -> amp + ppi l-leucyl-trna(leu), synthetase
• Biological source: THERMUS THERMOPHILUS
• Total number of polymer chains: 1
• Total formula weight: 102161.86

Authors

Cusack, S.,Yaremchuk, A.,Tukalo, M. (deposition date: 2003-01-30, release date: 2003-05-09, Last modification date: 2023-12-13)

Primary citation

Lincecum, T.,Tukalo, M.,Yaremchuk, A.,Mursinna, R.,Williams, A.,Sproat, B.,Van Den Eynde, W.,Link, A.,Van Calenbergh, S.,Grotli, M.,Martinis, S.,Cusack, S.
Structural and Mechanistic Basis of Pre- and Posttransfer Editing by Leucyl-tRNA Synthetase
Mol.Cell, 11:951-, 2003

PubMed Abstract: The aminoacyl-tRNA synthetases link tRNAs with their cognate amino acid. In some cases, their fidelity relies on hydrolytic editing that destroys incorrectly activated amino acids or mischarged tRNAs. We present structures of leucyl-tRNA synthetase complexed with analogs of the distinct pre- and posttransfer editing substrates. The editing active site binds the two different substrates using a single amino acid discriminatory pocket while preserving the same mode of adenine recognition. This suggests a similar mechanism of hydrolysis for both editing substrates that depends on a key, completely conserved aspartic acid, which interacts with the alpha-amino group of the noncognate amino acid and positions both substrates for hydrolysis. Our results demonstrate the economy by which a single active site accommodates two distinct substrates in a proofreading process critical to the fidelity of protein synthesis.

PubMed: 12718881
DOI: 10.1016/S1097-2765(03)00098-4

Experimental method

X-RAY DIFFRACTION (2.1 Å)