Structural highlights
Function
[TGT_ZYMMO] Exchanges the guanine residue with 7-aminomethyl-7-deazaguanine in tRNAs with GU(N) anticodons (tRNA-Asp, -Asn, -His and -Tyr). After this exchange, a cyclopentendiol moiety is attached to the 7-aminomethyl group of 7-deazaguanine, resulting in the hypermodified nucleoside queuosine (Q) (7-(((4,5-cis-dihydroxy-2-cyclopenten-1-yl)amino)methyl)-7-deazaguanosine).[HAMAP-Rule:MF_00168]
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
The tRNA modifying enzyme tRNA-guanine transglycosylase (TGT) is involved in the exchange of guanine in the first position of the anticodon with preQ1 as part of the biosynthesis of the hypermodified base queuine (Q). Mutation of Ser90 to an alanine in Escherichia coli TGT leads to a dramatic reduction of enzymatic activity (Reuter, K. et al. (1994) Biochemistry 33, 7041-7046). To further clarify the role of this residue in the catalytic center, we have mutated the corresponding Ser103 of the crystallizable Zymomonas mobilis TGT into alanine. The crystal structure of a TGT(S103A)/preQ1 complex combined with biochemical data presented in this paper suggest that Ser103 is essential for substrate orientation in the TGT reaction.
Mutagenesis and crystallographic studies of Zymomonas mobilis tRNA-guanine transglycosylase to elucidate the role of serine 103 for enzymatic activity.,Gradler U, Ficner R, Garcia GA, Stubbs MT, Klebe G, Reuter K FEBS Lett. 1999 Jul 2;454(1-2):142-6. PMID:10413112[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Gradler U, Ficner R, Garcia GA, Stubbs MT, Klebe G, Reuter K. Mutagenesis and crystallographic studies of Zymomonas mobilis tRNA-guanine transglycosylase to elucidate the role of serine 103 for enzymatic activity. FEBS Lett. 1999 Jul 2;454(1-2):142-6. PMID:10413112
