Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.12.7.2 (hydrogenase)
 3,522 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Red blood cell membrane proteins were studied in a group of patients with hereditary spherocytosis, in comparison with normal donors, to reveal anomalous proteins associated with this disease. For this purpose red blood cells of the patients and normal donors were fractionated, by the age, in Ficoll-400 gradient, as a result red blood cell membranes were obtained with proteins that were investigated by the method of two-dimensional electrophoresis. In comparison of two-dimensional electrophoregrams of red blood cell membrane proteins of normal donors and those of microspherocytosis patients it was found that the latters had additional peptides in the area of glyceraldehyde-3-phosphate hydrogenase and pyruvate kinase. The changes detected in the red blood cell membrane protein composition might be caused by age shifts in the red blood cell population or by the disease type.
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PMID:[Erythrocyte membrane proteins in patients with hereditary spherocytosis]. 129 77

Cells of the aerotolerant anaerobe Giardia lamblia respire in the presence of oxygen. Endogenous respiration is stimulated by glucose but not by other carbohydrates and Krebs cycle intermediates. Endogenous and glucose-stimulated respiration are insensitive to cyanide, malonate, and 2,4-dinitrophenol, but are inhibited by atabrin and iodoacetamide. G. lamblia produces ethanol, acetate and CO2 both aerobically and anaerobically either from endogenous reserves or exogenous glucose. Molecular hydrogen is not produced. The following enzyme activities were detected in homogenates: hexokinase, fructose-biphosphate aldolase, pyruvate kinase, phosphoenolpyruvate carboxykinase, malate dehydrogenase, malate dehydrogenase (decarboxylating), pyruvate synthase, acetyl-CoA synthetase, alcohol dehydrogenase (NADP+), NADH dehydrogenase, NADPH dehydrogenase, NADPH oxidoreductase and superoxide dismutase. The enzymes of energy and carbohydrate metabolism are nonsedimentable (109 000 x g for 30 min). Activities of lactate dehydrogenase, hydrogenase, phosphate acetyltransferase, acetate kinase, citrate synthase, succinate dehydrogenase, fumarate hydratase and catalase were below the limits of detection. The results suggest the occurrence of glycolysis, energy production by substrate level phosphorylation and a flavin, iron-sulfur protein mediated electron transport system as well as the absence of cytochrome mediated oxidative phosphorylation and functional Krebs cycle.
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PMID:Energy metabolism of the anaerobic protozoon Giardia lamblia. 610 7

Thermoanaerobium brockii was shown to catabolize glucose via the Embden-Meyerhof-Parnas pathway into ethanol, acetic acid, H(2)-CO(2), and lactic acid. Radioactive tracer studies, employing specifically labeled [(14)C]glucose, demonstrated significant fermentation of (14)CO(2) from C-3 and C-4 of the substrate exclusively. All extracts contained sufficient levels of activity (expressed in micromoles per minute per milligram of protein at 40 degrees C) to assign a catabolic role for the following enzymes: glucokinase, 0.40; fructose-1,6-diphosphate aldolase, 0.23; glyceraldehyde-3-phosphate dehydrogenase, 1.73; pyruvate kinase, 0.36; lactate dehydrogenase (fructose-1,6-diphosphate activated), 0.55; pyruvate dehydrogenase (coenzyme A acetylating), 0.53; hydrogenase, 3.3; phosphotransacetylase, 0.55; acetaldehyde dehydrogenase (coenzyme A acetylating), 0.15; ethanol dehydrogenase, 1.57; and acetate kinase, 1.50. All pyridine nucleotide-linked oxidoreductases examined were specific for nicotinamide adenine dinucleotide, except ethanol dehydrogenase which displayed both nicotinamide adenine dinucleotide- and nicotinamide adenine dinucleotide phosphate-linked activities. Fermentation product balances and cell growth yields supported the glucose catabolic pathway described. Representative balanced end product yields (in moles per mole of glucose fermented) were: ethanol, 0.94; l-lactate, 0.84; acetate, 0.20; CO(2), 1.31; and H(2), 0.50. Growth yields of 16.4 g of cells per mole of glucose were demonstrated. Both growth and end product yields varied significantly in accordance with the specific medium composition and incubation time.
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PMID:Glucose fermentation pathway of Thermoanaerobium brockii. 676 5

A pathway for conversion of the metabolic intermediate phosphoenolpyruvate (PEP) and the formation of acetate, succinate, formate, and H2 in the anaerobic cellulolytic bacterium Ruminococcus flavefaciens FD-1 was constructed on the basis of enzyme activities detected in extracts of cells grown in cellulose- or cellobiose-limited continuous culture. PEP was converted to acetate and CO2 (via pyruvate kinase, pyruvate dehydrogenase, and acetate kinase) or carboxylated to form succinate (via PEP carboxykinase, malate dehydrogenase, fumarase, and fumarate reductase). Lactate was not formed even during rapid growth (batch culture, mu = 0.35/h). H2 was formed by a hydrogenase rather than by cleavage of formate, and 13C-NMR and 14C-exchange reaction data indicated that formate was produced by CO2 reduction, not by a cleavage of pyruvate. The distribution of PEP into the acetate and succinate pathways was not affected by changing extracellular pH and growth rates within the normal growth range. However, increasing growth rate from 0.017/h to 0.244/h resulted in a shift toward formate production, presumably at the expense of H2. This shift suggested that reducing equivalents could be balanced through formate or H2 production without affecting the yields of the major carbon-containing fermentation endproducts.
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PMID:Formation of formate and hydrogen, and flux of reducing equivalents and carbon in Ruminococcus flavefaciens FD-1. 929 88

In sycamore cells grown on nitrate as opposed to glutamate there is a higher pentose phosphate pathway carbon flux relative to glycolysis in the early stages of cell growth when nitrate assimilation is most active. The high pentose phosphate pathway activity compared with glycolysis in nitrate grown cells is accompanied by enhanced levels of hexokinase, pyruvate kinase, glucose-6-phosphate de-hydrogenase, 6-phosphogluconate dehydrogenase and transketolase. There is no significant increase in activity of the solely glycolytic enzyme, phosphofructokinase. It is suggested that the increased pentose phosphate pathway activity in nitrate grown cells is correlated with a demand by nitrite assimilation for NADPH.
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PMID:Interrelationships between carbohydrate metabolism and nitrogen assimilation in cultured plant cells : III. Effect of the nitrogen source on the pattern of carbohydrate oxidation in cells of Acer pseudoplatanus L. grown in culture. 2442 May 21