Structural highlights
Function
[SYI1_STAAU] Catalyzes the attachment of isoleucine to tRNA(Ile). As IleRS can inadvertently accommodate and process structurally similar amino acids such as valine, to avoid such errors it has two additional distinct tRNA(Ile)-dependent editing activities. One activity is designated as 'pretransfer' editing and involves the hydrolysis of activated Val-AMP. The other activity is designated 'posttransfer' editing and involves deacylation of mischarged Val-tRNA(Ile) (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Isoleucyl-transfer RNA (tRNA) synthetase (IleRS) joins Ile to tRNA(Ile) at its synthetic active site and hydrolyzes incorrectly acylated amino acids at its editing active site. The 2.2 angstrom resolution crystal structure of Staphylococcus aureus IleRS complexed with tRNA(Ile) and Mupirocin shows the acceptor strand of the tRNA(Ile) in the continuously stacked, A-form conformation with the 3' terminal nucleotide in the editing active site. To position the 3' terminus in the synthetic active site, the acceptor strand must adopt the hairpinned conformation seen in tRNA(Gln) complexed with its synthetase. The amino acid editing activity of the IleRS may result from the incorrect products shuttling between the synthetic and editing active sites, which is reminiscent of the editing mechanism of DNA polymerases.
Insights into editing from an ile-tRNA synthetase structure with tRNAile and mupirocin.,Silvian LF, Wang J, Steitz TA Science. 1999 Aug 13;285(5430):1074-7. PMID:10446055[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Silvian LF, Wang J, Steitz TA. Insights into editing from an ile-tRNA synthetase structure with tRNAile and mupirocin. Science. 1999 Aug 13;285(5430):1074-7. PMID:10446055
