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Your query returned 1 entry. Printable version
EC | 2.7.7.79 | ||||||||||||
Accepted name: | tRNAHis guanylyltransferase | ||||||||||||
Reaction: | p-tRNAHis + ATP + GTP + H2O = pGp-tRNAHis + AMP + 2 diphosphate (overall reaction) (1a) p-tRNAHis + ATP = App-tRNAHis + diphosphate (1b) App-tRNAHis + GTP = pppGp-tRNAHis + AMP (1c) pppGp-tRNAHis + H2O = pGp-tRNAHis + diphosphate |
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Glossary: | p-tRNAHis = 5′-phospho-ribonucleotide-[tRNAHis] pGp-tRNAHis = 5′-phospho-guanosine-ribonucleotide-[tRNAHis] App-tRNAHis = 5′-(5′-diphosphoadenosine)-ribonucleotide-[tRNAHis] pppGp-tRNAHis = 5′-triphospho-ribonucleotide-[tRNAHis] |
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Other name(s): | histidine tRNA guanylyltransferase; Thg1p (ambiguous); Thg1 (ambiguous) | ||||||||||||
Systematic name: | p-tRNAHis:GTP guanylyltransferase (ATP-hydrolysing) | ||||||||||||
Comments: | In eukarya an additional guanosine residue is added post-transcriptionally to the 5′-end of tRNAHis molecules. The addition occurs opposite a universally conserved adenosine73 and is thus the result of a non-templated 3′-5′ addition reaction. The additional guanosine residue is an important determinant for aminoacylation by EC 6.1.1.21, histidine—tRNA ligase.The enzyme requires a divalent cation for activity [2]. ATP activation is not required when the substrate contains a 5′-triphosphate (ppp-tRNAHis) [3]. | ||||||||||||
Links to other databases: | BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB | ||||||||||||
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