CATH Classification
Level | CATH Code | Description |
---|---|---|
3 | Alpha Beta | |
3.20 | Alpha-Beta Barrel | |
3.20.20 | TIM Barrel | |
3.20.20.105 | Queuine tRNA-ribosyltransferase-like |
Domain Context
CATH Clusters
Superfamily | Queuine tRNA-ribosyltransferase-like |
Functional Family | Queuine tRNA-ribosyltransferase |
Enzyme Information
2.4.2.29 |
tRNA-guanine(34) transglycosylase.
based on mapping to UniProt P28720
(1) Guanine(34) in tRNA + queuine = queuosine(34) in tRNA + guanine. (2) Guanine(34) in tRNA + 7-aminomethyl-7-carbaguanine = 7-aminomethyl-7- carbaguanine(34) in tRNA + guanine.
-!- Certain prokaryotic and eukaryotic tRNAs contain the modified base queuine at position 34. -!- In eukaryotes queuine is salvaged from food and incorporated into tRNA directly via a base-exchange reaction, replacing guanine. -!- In eubacteria, which produce queuine de novo, the enzyme catalyzes the exchange of guanine with the queuine precursor preQ(1), which is ultimately modified to queuine. -!- The eubacterial enzyme can also use an earlier intermediate, preQ(0), to replace guanine in unmodified tRNA(Tyr) and tRNA(Asn). -!- This enzyme acts after EC 1.7.1.13 in the queuine-biosynthesis pathway.
|
UniProtKB Entries (1)
P28720 |
TGT_ZYMMO
Zymomonas mobilis subsp. mobilis ZM4 = ATCC 31821
Queuine tRNA-ribosyltransferase
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PDB Structure
PDB | 2OKO |
External Links | |
Method | X-RAY DIFFRACTION |
Organism | Escherichia |
Primary Citation |
Glutamate versus Glutamine Exchange Swaps Substrate Selectivity in tRNA-Guanine Transglycosylase: Insight into the Regulation of Substrate Selectivity by Kinetic and Crystallographic Studies.
J.Mol.Biol.
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