1k9v
| |||||||
| , resolution 2.4Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structural evidence for ammonia tunelling across the (beta-alpha)8-barrel of the imidazole glycerol phosphate synthase bienzyme complex
OverviewOverview
Since reactive ammonia is not available under physiological conditions, glutamine is used as a source for the incorporation of nitrogen in a number of metabolic pathway intermediates. The heterodimeric ImGP synthase that links histidine and purine biosynthesis belongs to the family of glutamine amidotransferases in which the glutaminase activity is coupled with a subsequent synthase activity specific for each member of the enzyme family. Its X-ray structure from the hyperthermophile Thermotoga maritima shows that the glutaminase subunit is associated with the N-terminal face of the (beta alpha)(8) barrel cyclase subunit. The complex reveals a putative tunnel for the transfer of ammonia over a distance of 25 A. Although ammonia tunneling has been reported for glutamine amidotransferases, the ImGP synthase has evolved a novel mechanism, which extends the known functional properties of the versatile (beta alpha)(8) barrel fold.
About this StructureAbout this Structure
1K9V is a Single protein structure of sequence from Thermotoga maritima. Full crystallographic information is available from OCA.
ReferenceReference
Structural evidence for ammonia tunneling across the (beta alpha)(8) barrel of the imidazole glycerol phosphate synthase bienzyme complex., Douangamath A, Walker M, Beismann-Driemeyer S, Vega-Fernandez MC, Sterner R, Wilmanns M, Structure. 2002 Feb;10(2):185-93. PMID:11839304
Page seeded by OCA on Sun Mar 30 21:45:30 2008