1txg
|
Structure of glycerol-3-phosphate dehydrogenase from Archaeoglobus fulgidus
OverviewOverview
NAD(+)-dependent glycerol-3-phosphate dehydrogenase (G3PDH) is generally, absent in archaea, because archaea, unlike eukaryotes and eubacteria, utilize glycerol-1-phosphate instead of glycerol-3-phosphate for the, biosynthesis of membrane lipids. Surprisingly, the genome of the, hyperthermophilic archaeon Archaeoglobus fulgidus comprises a G3PDH, ortholog, gpsA, most likely due to horizontal gene transfer from a, eubacterial organism. Biochemical characterization proved G3PDH-like, activity of the recombinant gpsA gene product. However, unlike other, G3PDHs, the up to 85 degrees C thermostable A. fulgidus G3PDH exerted a, 15-fold preference for NADPH over NADH. The A. fulgidus G3PDH bears the, hallmarks of adaptation to halotolerance and thermophilicity, because its, 1.7-A crystal structure showed a high surface density for negative charges, and 10 additional intramolecular salt bridges compared to a mesophilic, G3PDH structure. Whereas all amino acid residues required for, dihydroxyacetone phosphate binding and reductive catalysis are highly, conserved, the binding site for the adenine moiety of the NAD(P), cosubstrate shows a structural variation that reflects the observed NADPH, preference, for example, by a putative salt bridge between R49 and the, 2'-phosphate.
About this StructureAbout this Structure
1TXG is a Single protein structure of sequence from Archaeoglobus fulgidus with SO4, NH4 and GOL as ligands. Active as Glycerol-3-phosphate dehydrogenase (NAD(P)(+)), with EC number 1.1.1.94 Full crystallographic information is available from OCA.
ReferenceReference
Structural and functional analysis of the gpsA gene product of Archaeoglobus fulgidus: a glycerol-3-phosphate dehydrogenase with an unusual NADP+ preference., Sakasegawa S, Hagemeier CH, Thauer RK, Essen LO, Shima S, Protein Sci. 2004 Dec;13(12):3161-71. PMID:15557260
Page seeded by OCA on Wed Nov 21 03:40:12 2007