Glycerol-3-Phosphate Dehydrogenase: Difference between revisions
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<StructureSection load='1yj8' size='350' side='right' scene='' caption='Glycerol-3-phosphate dehydrogenase trimer [[1yj8]]'> | |||
'''Glycerol 3- | |||
Glycerol 3-phosphate dehydrogenase (GlpD) is a membrane bound enzyme in prokaryotes and in eukaryotes. Glycerol 3-Phosphate Dehydrogenase (GlpD) is an oxidoreductase enzyme which catalyzes the reduction | '''Glycerol-3-phosphate dehydrogenase''' (GlpD) is a membrane bound enzyme in prokaryotes and in eukaryotes. Glycerol 3-Phosphate Dehydrogenase (GlpD) is an oxidoreductase enzyme which catalyzes the reduction in [http://en.wikipedia.org/wiki/File:Dihydroxyacetone_phosphate_to_glycerol_3-phosphate_en.svg reaction] of Dihydroxyacetone Phosphate to Glycerol 3-Phosphate, with NADH as the reductant. GlpD is involved in many cellular functions such as phospholipids biosynthesis, respiration and metabolism. <ref name="cellfunction">PMID:18296637</ref>The GlpD is a dimer consisting of two subunits which contain the catabolite activator protein (CAP)-Domain,the flavin adenine dinucleotide(FAD)-Domain and a ubiquinone analogue, MD. | ||
===Structure=== | ===Structure=== | ||
[[Image:FINAL.png|left|thumb|Glycerol 3-Phosphate Dehydrogenase]] | |||
{{Clear}} | |||
GlpD is a dimer that consists of two subunits; α and β. The GlpD structure also contains seven ligands; 1,3-Dihydroxyacetonephosphate (13P), β-Octylglucoside (βOG), 1,2-Ethanediol (EDO), Flavin-Adenine Dinucleotide (FAD), Imidazole (IMD), PO4 (Phosphate Ion) and N-(Tris(Hydroxymethyl)methyl)-3-Aminopropanesulfonic Acid (T3A). The active sites on GlpD are the Cap-Domain, FAD- Domain and a ubiquinone substrate analogue, menadione (MD). | GlpD is a dimer that consists of two subunits; α and β. The GlpD structure also contains seven ligands; 1,3-Dihydroxyacetonephosphate (13P), β-Octylglucoside (βOG), 1,2-Ethanediol (EDO), Flavin-Adenine Dinucleotide (FAD), Imidazole (IMD), PO4 (Phosphate Ion) and N-(Tris(Hydroxymethyl)methyl)-3-Aminopropanesulfonic Acid (T3A). The active sites on GlpD are the Cap-Domain, FAD- Domain and a ubiquinone substrate analogue, menadione (MD). | ||
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<scene name='Sandbox_189/Fad/2'>FAD Active Site</scene> | <scene name='Sandbox_189/Fad/2'>FAD Active Site</scene> | ||
The N-terminal FAD-Domain exists in each monomer subunit of GlpD and is embedded into the phospholipid membrane bilayer.Substrate binding occurs at this domain which causes a conformational change to the structure of the GlpD enzyme. The FAD-domain plays a major role in metabolism and energy synthesis. | The N-terminal FAD-Domain exists in each monomer subunit of GlpD and is embedded into the phospholipid membrane bilayer.Substrate binding occurs at this domain which causes a conformational change to the structure of the GlpD enzyme. The FAD-domain plays a major role in metabolism and energy synthesis. The active site is found in a cleft between the two domains<ref>PMID:14717590</ref>. | ||
===Function=== | ===Function=== | ||
GlpD functions in the intracellular membrane of E. coli and in the inner-mitochondrial membrane of eukaryotes. In E. Coli, GlpD catalyzes and reduces the reaction of dihydroxyacetone phosphate to glycerol 3-phosphate in the [http://www.pnas.org/content/105/9/3280/F1.large.jpg glycerol metabolism pathway]. The binding of the substrate analogues (glyceraldehydes 3-phosphate, glyceric acid 2-phosphate and phosphoenolpyruvate, dihydroxyacetone phosphate)or UQ substrate analogues (2-n-heptyl-4-hydroxyquinoline N-oxide and menadione). The conformational change of the structure and resiudes of GlpD catalyzes many different metabolic reactions. | GlpD functions in the intracellular membrane of E. coli and in the inner-mitochondrial membrane of eukaryotes. In E. Coli, GlpD catalyzes and reduces the reaction of dihydroxyacetone phosphate (DHAP) to glycerol 3-phosphate in the [http://www.pnas.org/content/105/9/3280/F1.large.jpg glycerol metabolism pathway]. The binding of the substrate analogues (glyceraldehydes 3-phosphate, glyceric acid 2-phosphate and phosphoenolpyruvate, dihydroxyacetone phosphate) or UQ substrate analogues (2-n-heptyl-4-hydroxyquinoline N-oxide and menadione). The conformational change of the structure and resiudes of GlpD catalyzes many different metabolic reactions. | ||
===Metabolic Pathways=== | |||
====Phosphoplipid Biosynthesis==== | ====Phosphoplipid Biosynthesis==== | ||
GlpD reduces | GlpD reduces DHAP to glycerol 3-phosphate. Then the glycerol 3-phosphate is catalyzed by acyl transferase to 1-acylglyverol-3-phosphate, and then another acyl transferase catalyzes that to a phosphatidic acid. head groups are added to the phosphatidic acid to synthesize phospholipids. | ||
==== | ====Glyceroneogenesis==== | ||
GlpD is also involved in the glyceroneogenesis pathway. By gluconeogenesis, phosphoenolpyruvate converts to dihydroxyacetone phosphate which is reduced by GlpD to glycerol 3-phosphate which then forms a backbone for the synthesis of triacylglycerol. | |||
==== | ====Respiration==== | ||
The FAD-domain in GlpD plays a major role in the transport of electrons into the repiratory pathway. Glycerol 3-phosphate is oxidized to dihydroxyacetone phosphate with simultaneous reduction of of FAD to FADH2 occuring, and the electrons are transported to Ubiquinone, which are further transported to oxygen or nitrogen and into the respiratory pathway. | |||
===Diseases=== | ===Diseases=== | ||
GlpD is involved in diseases such as Alzeheimer`s, muscle dystrophy, hyaline membrane diseases and many more. | |||
==3D structures of glycerol-3-phosphate dehydrogenase== | |||
[[Glycerol-3-phosphate dehydrogenase 3D structures]] | |||
</StructureSection> | |||
==References== | |||
<references /> | |||
[[Category:Topic Page]] | |||