1xzp
From Proteopedia
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| , resolution 2.3Å | |||||||
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| Ligands: | |||||||
| Gene: | TrmE (Thermotoga maritima) | ||||||
| Related: | 1XZQ
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structure of the GTP-binding protein TrmE from Thermotoga maritima
Overview
TrmE is a 50 kDa guanine nucleotide-binding protein conserved between bacteria and man. It is involved in the modification of uridine bases (U34) at the first anticodon (wobble) position of tRNAs decoding two-family box triplets. The precise role of TrmE in the modification reaction is hitherto unknown. Here, we report the X-ray structure of TrmE from Thermotoga maritima. The structure reveals a three-domain protein comprising the N-terminal alpha/beta domain, the central helical domain and the G domain, responsible for GTP binding and hydrolysis. The N-terminal domain induces dimerization and is homologous to the tetrahydrofolate-binding domain of N,N-dimethylglycine oxidase. Biochemical and structural studies show that TrmE indeed binds formyl-tetrahydrofolate. A cysteine residue, necessary for modification of U34, is located close to the C1-group donor 5-formyl-tetrahydrofolate, suggesting a direct role of TrmE in the modification analogous to DNA modification enzymes. We propose a reaction mechanism whereby TrmE actively participates in the formylation reaction of uridine and regulates the ensuing hydrogenation reaction of a Schiff's base intermediate.
About this Structure
1XZP is a Protein complex structure of sequences from Thermotoga maritima. Full crystallographic information is available from OCA.
Reference
The structure of the TrmE GTP-binding protein and its implications for tRNA modification., Scrima A, Vetter IR, Armengod ME, Wittinghofer A, EMBO J. 2005 Jan 12;24(1):23-33. Epub 2004 Dec 16. PMID:15616586
Page seeded by OCA on Mon Mar 31 00:56:58 2008
