Embden-Meyerhoff pathway

Pyruvate is the initial key intermediate in butyric acid fermentations and is formed via the Embden-Meyerhoff pathway. Pyruvate is cleaved to form CO2, H2, and acetyl-Coenzyme A (acetyl-CoA), which dimerizes to form acet-oacetyl-CoA ... 

Glycolysis is a series of ten enzyme-catalyzed reactions that break down glucose into 2 equivalents of pyruvate, CH3C0C02". The steps of glycolysis, also called the Embden-Meyerhoff pathway after its discoverers, are summarized in Figure 29.4 (p. 1204). 

Bodner, G. M. Metabolism Part I, Glycolysis, or the Embden-Meyerhoff Pathway./ Chem. Ed. 63, 566-570 (1986). [A clear, concise summary of the pathway. Part of a series on metabolism of carbohydrates and lipids.]... 

Metabolic shifts may occur in several fruits during ripening. For example, during ripening of bananas, there is a marked rise in aldolase and carboxylase activities and thus it appears that at this stage the Embden-Meyerhoff pathway becomes dominant and the pentose-phosphate pathway is suppressed. 

The strictly homofermentative lactobacilli do not ferment pentose, and form two molecules of lactic acid from one molecule of glucose by the Embden-Meyerhoff pathway. 

Rg. 9.8. Fermentation of glucose to acetate or lactate via the Embden-MeyerhofF-Pamas pathway. 

Aerobic glycolysis first involves a ten-step conversion of glucose to pyruvic acid or pyruvate, called the Embden-Meyerhoff-Pamas pathway, followed by its further conversion to carbon dioxide and water via what is variously called the tricarboxylic acid cycle, or citric acid cycle, or Krebs cycle after its discoverer. The net products discharged from the cycle are carbon dioxide and water, with recycle of a further product called oxaloacetic acid or oxaloacetate. Successive organic acids that contain three carboxyl groups (-COOH), are initially involved in the cycle starting with citric acid or a neutral salt of citric acid (citrate). Hence the designator tricarboxylic. 

C4H7O7P, Mr 198.07 (dianion). Occurs in trace amounts in muscles. E. is an important intermediate in the Embden-Meyerhoff-Pamas pathway for glycolysis and a precursor in the biosynthesis of 3-deoxy-D-nra/rino-2-heptulosonic acid 7-phospbate (DAMP). 

Figures 4 and 5 illustrates the use of NMR spectroscopy to study the metabolism of (l-i C)glu-cose in primary cultures of neurons and astrocytes. A simplified scheme of the metabolism of (l-i C)glu-cose in neural cells is given in Figure 4. Briefly, (1-i C)glucose is metabolized to (3- C)pyruvate through the Embden Meyerhoff glycolytic pathway. The (3-i C)pyruvate produced can be transaminated to (3- C)alanine, reduced to (3-i C)lactate or enter the tricarboxylic acid (TCA) cycle through the pyruvate dehydrogenase (PDH) or pyruvate carboxylase (PC) activities. A net increase in (3-i C)lactate reveals increased aerobic glycolysis and is normally observed under hypoxic conditions in normal cells. If (3-i C)pyruvate enters the TCA cycle though PDH it produces (2-i C)acetyl-coenzyme A first, and subsequently (4-i C)a-ketoglutarate. In contrast, if (3-i C)pyruvate is carboxylated to (3-i C)oxalacetate by...

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