Glyoxylate metabolism

Ornston LN, MK Ornston (1969) Regulation of glyoxylate metabolism in Escherichia coli K-12. J Bacterial 98 1098-1108. 

Primary hyperoxaluria type I (PH I) (Fig. 20.2) is a rare, autosomal recessive inherited disease caused by a defect in glyoxylate metabolism with low or absent activity of liver-specific peroxisomal ala-nine-glyoxylate aminotransferase (ACT) (Danpure 1989). The AGXT gene is located on chromosome 2q36-37 (Purdue et al. 1991). The disease prevalence is two patients per million population (Kopp and Leumann 1995) in Europe. 

Primary hyperoxaluria type I (McKusick 25 990) is a rare autosomal recessively inherited disorder of glyoxylate metabolism in which patients... 

It has been shown to metabolize trifluoroethene to glyoxylate, difluoroacetate, and the rearranged product trifluoroacetaldehyde (Fox et al. 1990). The last reaction is analogous to the formation of trichloroacetaldehyde from trichloroethene by the same strain (Oldenhuis et al. 1989). 

Formate metabolism is the most obscure sector of the plant C network, and the one where the genome has yielded the most surprises.3 Plants have formate pools that are important sources of Ci units,24"27 and plants also have formate dehydrogenase activity.28 31 However, the origin of formate is not clear. It may come from non-enzymatic decarboxylation of glyoxylate in leaves in the light,27 32 but this cannot be... 

WINGLER, A., LEA, P.J., LEEGOOD, R.C., Photorespiratory metabolism of glyoxylate and formate in glycine-accumulating mutants of barley and Amaranthus edulis, Planta, 1999, 207,518-526. 

E. M. T. El Mansi, G. C. Dawson, and C. F. A. Bryce, Steady state modeling of metabolic flux between the tricarboxylic cycle and the glyoxylate bypass in Escherichia coli. CABIOS (now Bioinformatics) 10(3), 295 299 (1994). 

Fig. 9. Pathway duplication the methyl citrate cycle and the glyoxylate shunt. A pathway for acetate metabolism in E. coli that uses the glyoxylate shunt is depicted on the right. Part of the methyl citrate cycle, a pathway for propionate metabolism, is depicted on the left. The pathways are analogous furthermore, three of the four steps are catalyzed by homologous enzymes. PrpE (propionyl-CoA synthase) is homologous to AcsA (acetyl-CoA synthase). PrpC (2-methyl-citrate synthase) is homologous to GltA (citrate synthase). PrpB (2-methyl-isocitrate lyase) is homologous to AceA (isocitrate lyase). The third step in the methyl citrate cycle has been suggested to be catalyzed by PrpD the second half of the reaction (the hydration) can be catalyzed by aconitase.

Fructose and mannose metabolism Galactose metabolism Ascorbate and aldarate metabolism Pyruvate metabolism Glyoxylate and dicarboxylate metabolism... 

Rotte C, Stejskal F, Zhu G, Keithly JS, Martin W (2001) Pyruvate NADP+ oxidoreductase from the mitochondrion of Euglena gracilis and from the apicomplexan Cryptosporidium parvum a biochemical relic linking pyruvate metabolism in mitochondriate and amitochondriate protists. Mol Biol Evol 18 710-720 Schnarrenberger C, Martin W (2002) Evolution of the enzymes of the citric acid cycle and the glyoxylate cycle of higher plants. A case study of endosymbiotic gene transfer. Eur J Biochem 269 868-883... 

The same intermediates of glycolysis and the citric acid cycle that activate isocitrate dehydrogenase are allosteric inhibitors of isocitrate lyase. When energy-yielding metabolism is sufficiently fast to keep the concentrations of glycolytic and citric acid cycle intermediates low, isocitrate dehydrogenase is inactivated, the inhibition of isocitrate lyase is relieved, and isocitrate flows into the glyoxylate pathway, to be used in the biosynthesis of carbohydrates, amino acids, and other cellular components. 

Peroxisomes are rich in enzymes that produce and decompose hydrogen peroxide. They often make a major contribution to the oxidative metabolism of cells. In germinating oilseeds glyoxysomes, a type of peroxisome, contain enzymes that catalyze reactions of the biosynthetic "glyoxylate pathway" of metabolism.51 Organelles that resemble peroxisomes in appearance... 

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