Publications

• 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 C.H., Thauer R.K., Essen L.-O., Shima S.

  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 arc ... >> More

  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. << Less

  Protein Sci. 13:3161-3171(2004) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Biosynthesis in Escherichia coli of sn-glycerol-3-phosphate, a precursor of phospholipid. Further kinetic characterization of wild type and feedback-resistant forms of the biosynthetic sn-glycerol-3-phosphate dehydrogenase.

  Edgar J.R., Bell R.M.

  J Biol Chem 255:3492-3497(1980) [PubMed] [EuropePMC]

• Biosynthesis in Escherichia coli of sn-glycerol 3-phosphate, a precursor of phospholipid.

  Edgar J.R., Bell R.M.

  J. Biol. Chem. 253:6348-6353(1978) [PubMed] [EuropePMC]

• Purification and regulatory properties of the biosynthetic L-glycerol 3-phosphate dehydrogenase from Escherichia coli.

  Kito M., Pizer L.I.

  J Biol Chem 244:3316-3323(1969) [PubMed] [EuropePMC]

• Biosynthesis in Escherichia coli of sn-glycerol 3-phosphate, a precursor of phospholipid. Kinetic characterization of wild type and feedback-resistant forms of the biosynthetic sn-glycerol-3-phosphate dehydrogenase.

  Edgar J.R., Bell R.M.

  Homogeneous wild type and feedback-resistant forms of the biosynthetic sn-glycerol 3-phosphate (glycerol-P) dehydrogenase of Escherichia coli (EC1.1.1.8) were subjected to two-substrate kinetic analysis. The kinetics of the NADPH-dependent reduction of dihydroxyacetone phosphate (dihydroxyacetone- ... >> More

  Homogeneous wild type and feedback-resistant forms of the biosynthetic sn-glycerol 3-phosphate (glycerol-P) dehydrogenase of Escherichia coli (EC1.1.1.8) were subjected to two-substrate kinetic analysis. The kinetics of the NADPH-dependent reduction of dihydroxyacetone phosphate (dihydroxyacetone-P) and of the NADP-dependent oxidation of glycerol-P indicate that these reactions proceed by a sequential mechanism. Glycerol-P was a competitive inhibitor with respect to dihydroxyacetone-P for both enzymes. The wild type and feedback-resistant glycerol-P dehydrogenases had Ki values for glycerol-P of 4.4 micrometer and 43 micrometer, respectively. Therefore, the sensitivity of the wild type activity and reduced sensitivity of the feedback-resistant activity, both noted previously in crude extracts, were inherent properties of the enzymes. The patterns of product inhibition for both enzymes were identical, and the difference in the inhibition constants for glycerol-P occurred without significant alteration of any other kinetic constant determined. Kinetic mechanisms consistent with the patterns of product inhibition violated Haldane relationships and other kinetic relationships. These discrepancies suggest that glycerol-P inhibition occurs at a site distinct from the active site. The pH dependencies of the Km for dihydroxyacetone-P and the Ki for glycerol-P were markedly different suggesting the existence of an allosteric site. The addition of glycerol-P in the presence of NADPH stabilized both enzymes against thermal inactivation. Half-maximal stabilization was provided by 5 micrometer and 50 micrometer glycerol-P for the wild type and feedback-resistant enzymes, respectively. These kinetic data, considered in conjunction with previous physiologic and genetic data, indicate that the synthesis of glycerol-P is regulated in vivo by glycerol-P inhibition of the glycerol-P dehydrogenase. The data suggest that glycerol-P inhibition occurs at an allosteric, regulatory site. << Less

  J. Biol. Chem. 253:6354-6363(1978) [PubMed] [EuropePMC]