Lactate glycolysis

Hanson, A.D. Jacobsen, J.V. (1984). Control of lactate dehydrogenase, lactate glycolysis and a-amylase of O2 deficit in barley aleurone layers. Plant Physiology, 75, 566-72. 

Table 9.7 Effect of aerobic physical training on the maximum capacity for ATP generation from conversion of glycogen to lactate (glycolysis) and complete oxidation of glucose (the Krebs cycle) in the guadriceps muscle of male and female volunteers...

In most biochemical reactions the pH of the medium is close to 7 At this pH car boxylic acids are nearly completely converted to their conjugate bases Thus it is common practice m biological chemistry to specify the derived carboxylate anion rather than the carboxylic acid itself For example we say that glycolysis leads to lactate by way of pyruvate... 

The process of glycolysis converts some, but not all, of the metabolic energy of the glucose molecule into ATP. The free energy change for the conversion of glucose to two molecules of lactate (the anaerobic route shown in Figure 19.1) is -183.6 kj/mol ... 

Glycolysis A net formation of two results from the formation of lactate from one molecule of glucose, generated in two reactions catalyzed by phospho-glycerate kinase and pyruvate kinase, respectively (Figure 17-2). 

Glucose is metabolized to pyruvate by the pathway of glycolysis, which can occur anaerobically (in the absence of oxygen), when the end product is lactate. Aerobic tissues metabolize pyruvate to acetyl-CoA, which can enter the citric acid cycle for complete oxidation to CO2 and HjO, linked to the formation of ATP in the process of oxidative phosphorylation (Figure 16-2). Glucose is the major fuel of most tissues. 

Glycolysis, the pentose phosphate pathway, and fatty acid synthesis are all found in the cytosol. In gluconeo-genesis, substrates such as lactate and pyruvate, which are formed in the cytosol, enter the mitochondrion to yield oxaloacetate before formation of glucose. 

The overall equation for glycolysis from glucose to lactate is as follows ... 

This is true of skeletal muscle, particularly the white fibers, where the rate of work output—and therefore the need for ATP formation—may exceed the rate at which oxygen can be taken up and utilized. Glycolysis in erythrocytes, even under aerobic conditions, always terminates in lactate, because the subsequent reactions of pymvate are mitochondrial, and erythrocytes lack mitochondria. Other tissues that normally derive much of their energy from glycolysis and produce lactate include brain, gastrointestinal tract, renal medulla, retina, and skin. The liver, kidneys, and heart usually take up... 

Glycolysis is the cytosohc pathway of all mammalian cells for the metabohsm of glucose (or glycogen) to pyruvate and lactate. 

Lactate is the end product of glycolysis under anaerobic conditions (eg, in exercising muscle) or when the metabolic machinery is absent for the further oxidation of pyruvate (eg, in erythrocytes). 

Brain Coordination of the nervous system Glycolysis, amino acid metabolism Glucose, amino acid, ketone bodies (in starvation) Polyunsaturated fatty acids in neonate Lactate ... 

Muscle Fast twitch Slow twitch Rapid movement Sustained movement Glycolysis Aerobic pathways, eg, p-oxidation and citric acid cycle Glucose Ketone bodies, triacylglycerol in VLDL and chylomicrons, free fatty acids Lactate Lipoprotein lipase. Respiratory chain well developed. 

Erythrocytes Transport of O2 1 Glycolysis, pentose phosphate pathway. No mitochondria and therefore no p-oxidation or citric acid cycle. Glucose Lactate 1 (Hemoglobin) ... 

Gluconeogenesis Formation of glucose from precursors other than carbohydrates (especially by the liver and kidney) using amino acids from proteins, glycerol from fats, or lactate produced by muscle during anaerobic glycolysis. 

Deficiencies of enzymes involved in glycolysis, the hexose monophosphate pathway, the closely related glutathione metabolism and synthesis, and nucleotide metabolism have emerged as causes of hereditary nonspherocytic hemolytic anemias (Table 1) (F10, Fll, M27). Some enzyme deficiencies, such as diphospho-glycerate mutase deficiency, lactate dehydrogenase deficiency, and NADH cy-... 

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