Glu-tRNAGln amidotransferase or glutaminyl-tRNA synthase (glutamine-hydrolysing) enzyme (EC 6.3.5.7) is an amidotransferase that catalyzes the conversion of the non-cognate amino acid glutamyl-tRNAGln to the cognate glutaminyl-tRNAGln..[1] It catalyzes the reaction:
| Glutaminyl-tRNA synthase (glutamine-hydrolyzing) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 6.3.5.7 | ||||||||
| CAS no. | 52232-48-1 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
- ATP + glutamyl-tRNAGln + L-glutamine ADP + phosphate + glutaminyl-tRNAGln + L-glutamate
This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds carbon-nitrogen ligases with glutamine as amido-N-donor. The systematic name of this enzyme class is glutamyl-tRNAGln:L-glutamine amido-ligase (ADP-forming). This enzyme participates in glutamate metabolism and alanine and aspartate metabolism.
Function and evolutionary significance
editMost bacterial and all archaea genomes do not encode a glutaminyl-tRNA synthetase (GlnRS).[1] Instead they first synthesize the attachment of an amino acid on the tRNAGln by first attaching a non-cognate glutamate to the tRNA. Then these organisms use the amidotransferase: glutaminyl-tRNA synthase (glutamine-hydrolysing) (EC 6.3.5.7) enzyme to convert the glutamate attached to tRNAGln to glutamine. [1]
References
edit- ^ a b c Sheppard K, Yuan J, Hohn MJ, Jester B, Devine KM, Söll D (April 2008). "From one amino acid to another: tRNA-dependent amino acid biosynthesis". Nucleic Acids Research. 36 (6): 1813–1825. doi:10.1093/nar/gkn015. PMC 2330236. PMID 18252769.
