L-Glycerol-3-phosphate dehydrogenase

L-Glycerol-3-phosphate dehydrogenase (GDH, from rabbit muscle) [9075,65-4] M4 78,000... 

L-Glycerol-3-phosphate dehydrogenase (GDH, from rabbit muscle) [9075,65-4] M4 78,000 [EC 1.1.1.8]. Recrystd by adding (NH4)2S(>4 till 0.45 saturation at pH 5.5 at 4° and the small amount of ppte is removed then satd (NH4)2S04 is added dropwise from time to time over several days in the cold room. 

L-Glycerol-3-phosphate dehydrogenase (GDH, from rabbit muscle) [9075-65-4] Mr 78,000 [EC 1.1.1.8]. Recrystd by adding (NH4)2S04 till 0.45 saturation at pH 5.5 at 4° and the small amount of ppte is removed then satd (NH4)2S04 is added dropwise from time to time over several days in the cold room. The crystals are collected and recrystd until they have maximum activity. The enzyme is stable in half saturated (NH4)2S04 for several weeks at 4°. The equilibrium [dihydroxyacetone][NADH][H ]/[G-3-P][NAD] is 1.0 x lO M in Tris buffer at 25°. It uses NAD ten times more efficiently than NADP. The Km for G-3-P is 1.1 x 10 M, for NAD it is 3.8 x lO M and for dihydroxyacetone it is 4.6 x lO M in phosphate buffer pH 7.0 and at 23.3°. Dihydroxyacetone phosphate and fructose-1,6-diphosphate are inhibitors. [Branowski J Biol Chem 180 515 1949, The Enzymes 7 85 1963, Young and Pace Arch Biochem Biophys 75 125 1958 Walsh and Sallach Biochemistry 4 1076 1965.]... 

Another pathway is the L-glycerol 3-phosphate shuttle (Figure 11). Cytosolic dihydroxyacetone phosphate is reduced by NADFl to s.n-glycerol 3-phosphate, catalyzed by s,n-glycerol 3-phosphate dehydrogenase, and this is then oxidized by s,n-glycerol 3-phosphate ubiquinone oxidoreductase to dihydroxyacetone phosphate, which is a flavoprotein on the outer surface of the inner membrane. By this route electrons enter the respiratory chain.from cytosolic NADH at the level of complex III. Less well defined is the possibility that cytosolic NADH is oxidized by cytochrome bs reductase in the outer mitochondrial membrane and that electrons are transferred via cytochrome b5 in the endoplasmic reticulum to the respiratory chain at the level of cytochrome c (Fischer et al., 1985). 

The ratio [NAD+]/[NADH] appears to be maintained at a relatively constant value and in equilibrium with a series of different reduced and oxidized substrate pairs. Thus, it was observed that in the cytoplasm of rat liver cells, the dehydrogenations catalyzed by lactate dehydrogenase, sn-glycerol 3-phosphate dehydrogenase, and malate dehydrogenase are all at equilibrium with the same ratio of [NAD+]/[NADH].166 In one experiment rat livers were removed and frozen in less than 8 s by "freeze-clamping" (Section L,2) and the concentrations of different components of the cytoplasm determined167 the ratio [NAD+] / [NADH] was found to be 634, while the ratio of [lactate]/[pyruvate] was 14.2. From these values an... 

Valadi A, Granath K, Gustafsson L, Adler L (2004) Distinct intracellular localization of Gpdlp and Gpd2p, the two yeast isoforms of NAD+-dependent glycerol-3-phosphate dehydrogenase, explains their different contributions to redox-driven glycerol production. J Biol Chem 279 39677-39685... 

Nilsson, A. Adler, L. (1990). Purification and characterisation of glycerol-3-phosphate dehydrogenase (NAD+) in the salt tolerant yeast Debaryomyces hansenii. Biochimica et Biophysica Acta, 1034, 180-185. 

The oxidation of L-glycerol 3-phosphate to dihydroxyacetone phosphate is catalyzed by two different enzymes. One is the cytoplasmic NAD-linked a-glycerophosphate dehydrogenase, and the other is the mitochondrial enzyme, which appears to contain flavin and iron. The latter enzyme was first studied by Green in 1936 (223). It was shown to be associated with respiratory particles, and widely distributed in animal tissues. The highest concentration of the enzyme was found in the brain. Lardy and co-workers (234) studied the enzyme in deoxycholate-solubilized particles obtained from skeletal muscle, confirmed the finding... 

Brown, L., MacDonald, M., Lehn, D., and Moran, S. M. (1994]. Sequence of rat mitochondrial glycerol-3 phosphate dehydrogenase cDNA. /. Bioi. Chem. 269,14363-14366. 

L. P. Kozak, U.C. Kozak, and C.T. Clarke, Abnormal brown and white fat development in transgenic mice overexpressing glycerol 3-phosphate dehydrogenase, Genes Dev., 1991, 5, 2256-2264. 

DHAP can be diverted from its precursor role in ether lipid synthesis by conversion to jn-glycerol-3-phosphate by NADH glycerol-3-phosphate dehydrogenase. Another bypass that prevents the formation of alkyl-DHAP occurs if the ketone function of acyl-DHAP is first reduced by an NADPH-dependent oxidoreductase, since the product, l-acyl-2-lyso-in-glycerol-3-phosphate, can then be converted only to diacylglycerolipids. The metabolic removal and/or formation of fatty alcohols, DHAP, or acyl-DHAP from the ether lipid precursor pool may control ether lipid synthesis and accumulation. 

Vigeolas, H., P. Waldeck, T. Zank, and P. Geigenberger. 2007. Increasing seed oil content in oilseed rape (Brassica napus L.) by over-expression of a yeast glycerol-3-phosphate dehydrogenase under the control of a seed-specific promoter. Plant Biotech. J. 5 431 441. 

Michnick, S., Roustan, J.-L., Remize, F, Barre, R, Dequin, S. (1997). Modulation of glycerol and ethanol yields during alcoholic fermentation in Saccharomyces cerevisiae strains overexpressed or disrupted for GPDl encoding glycerol 3-phosphate dehydrogenase. Yeast, 13, 783-793. 

AnseU, R., Granath, K., Hohmann, S., Thevelein, J. M., Adler, L. (1997). The two isoenzymes for yeast NAD+-dependent glycerol 3-phosphate dehydrogenase encoded by GPDl and GPD2 have distinct roles in osmo-adaptation and redox regulation. EMBO Journal, 16, 2179-2187. 

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