First time at Proteopedia? Click on the green links: they change the 3D image. Click and drag the molecules. Proteopedia is a 3D, interactive encyclopedia of proteins, RNA, DNA and other molecules. With a free user account, you can edit pages in Proteopedia. Visit the Main Page to learn more.
1r6u
From Proteopedia
| 1r6u, resolution 2.00Å () | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||||
| Non-Standard Residues: | |||||||||
| Gene: | WARS (Homo sapiens) | ||||||||
| Activity: | Tryptophan--tRNA ligase, with EC number 6.1.1.2 | ||||||||
| Domains: | TrpRS_core | ||||||||
| Related: | 1r6t, 1n3l, 1ntg | ||||||||
| |||||||||
| |||||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Crystal structure of an active fragment of human tryptophanyl-tRNA synthetase with cytokine activity
Higher eukaryote tRNA synthetases have expanded functions that come from enlarged, more differentiated structures that were adapted to fit aminoacylation function. How those adaptations affect catalytic mechanisms is not known. Presented here is the structure of a catalytically active natural splice variant of human tryptophanyl-tRNA synthetase (TrpRS) that is a potent angiostatic factor. This and related structures suggest that a eukaryote-specific N-terminal extension of the core enzyme changed substrate recognition by forming an active site cap. At the junction of the extension and core catalytic unit, an arginine is recruited to replace a missing landmark lysine almost 200 residues away. Mutagenesis, rapid kinetic, and substrate binding studies support the functional significance of the cap and arginine recruitment. Thus, the enzyme function of human TrpRS has switched more to the N terminus of the sequence. This switch has the effect of creating selective pressure to retain the N-terminal extension for functional expansion.
Functional and crystal structure analysis of active site adaptations of a potent anti-angiogenic human tRNA synthetase., Yang XL, Guo M, Kapoor M, Ewalt KL, Otero FJ, Skene RJ, McRee DE, Schimmel P, Structure. 2007 Jul;15(7):793-805. PMID:17637340
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
1R6U is a 2 chains structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
- Yang XL, Guo M, Kapoor M, Ewalt KL, Otero FJ, Skene RJ, McRee DE, Schimmel P. Functional and crystal structure analysis of active site adaptations of a potent anti-angiogenic human tRNA synthetase. Structure. 2007 Jul;15(7):793-805. PMID:17637340 doi:10.1016/j.str.2007.05.009
Page seeded by OCA on Tue Feb 17 13:13:00 2009
