The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform
Jerzy Macioszek - One of the best experts on this subject based on the ideXlab platform.
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Isolation of chloroplastic Phosphoglycerate Kinase. Kinetics of the two-enzyme Phosphoglycerate Kinase/glyceraldehyde-3-phosphate dehydrogenase couple.
Plant Physiology, 1990Co-Authors: Jerzy Macioszek, James B. Anderson, Louise E. AndersonAbstract:We report here a method for the isolation of high specific activity Phosphoglycerate Kinase (EC 2.7.2.3) from chloroplasts. The enzyme has been purified over 200-fold from pea (Pisum sativum L.) stromal extracts to apparent homogeneity with 23% recovery. Negative cooperativity is observed with the two enzyme Phosphoglycerate Kinase/glyceraldehyde-3-P dehydrogenase (EC 1.2.1.13) couple restored from the purified enzymes when NADPH is the reducing pyridine nucleotide, consistent with earlier results obtained with crude chloroplastic extracts (J Macioszek, LE Anderson [1987] Biochim Biophys Acta 892: 185-190). Michaelis Menten kinetics are observed when 3-Phosphoglycerate is held constant and Phosphoglycerate Kinase is varied, which suggests that Phosphoglycerate Kinase-bound 1,3-bisPhosphoglycerate may be the preferred substrate for glyceraldehyde-3-P dehydrogenase in the chloroplast.
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Kinetics oftheTwo-Enzyme Phosphoglycerate Kinase/Glyceraldehyde-3-Phosphate Dehydrogenase Couple
1990Co-Authors: Jerzy MacioszekAbstract:We report herea methodfortheisolation ofhighspecific activity Phosphoglycerate Kinase (EC2.7.2.3) fromchloroplasts. Theenzymehasbeenpurified over200-fold frompea(Pisum sativum L.)stromal extracts toapparent homogeneity with23% recovery. Negative cooperativity isobserved withthetwoenzyme Phosphoglycerate Kinase/glyceraldehyde-3-P dehydrogenase (EC1.2.1.13) couple restored fromthepurified enzymeswhen NADPHisthereducing pyridine nucleotide, consistent withearlier results obtained withcrudechloroplastic extracts (JMacioszek, LEAnderson [1987] Biochim Biophys Acta892:185-190). Michaelis Mentenkinetics areobserved when3-Phosphoglycerate isheldconstant andPhosphoglycerate Kinase isvaried, which suggests thatPhosphoglycerate Kinase-bound 1,3-bisPhosphoglycerate maybethepreferred substrate forglyceraldehyde-3-P dehydrogenase inthechloroplast.
Louise E. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Isolation of chloroplastic Phosphoglycerate Kinase. Kinetics of the two-enzyme Phosphoglycerate Kinase/glyceraldehyde-3-phosphate dehydrogenase couple.
Plant Physiology, 1990Co-Authors: Jerzy Macioszek, James B. Anderson, Louise E. AndersonAbstract:We report here a method for the isolation of high specific activity Phosphoglycerate Kinase (EC 2.7.2.3) from chloroplasts. The enzyme has been purified over 200-fold from pea (Pisum sativum L.) stromal extracts to apparent homogeneity with 23% recovery. Negative cooperativity is observed with the two enzyme Phosphoglycerate Kinase/glyceraldehyde-3-P dehydrogenase (EC 1.2.1.13) couple restored from the purified enzymes when NADPH is the reducing pyridine nucleotide, consistent with earlier results obtained with crude chloroplastic extracts (J Macioszek, LE Anderson [1987] Biochim Biophys Acta 892: 185-190). Michaelis Menten kinetics are observed when 3-Phosphoglycerate is held constant and Phosphoglycerate Kinase is varied, which suggests that Phosphoglycerate Kinase-bound 1,3-bisPhosphoglycerate may be the preferred substrate for glyceraldehyde-3-P dehydrogenase in the chloroplast.
Jacky L Snoep - One of the best experts on this subject based on the ideXlab platform.
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Phosphoglycerate Kinase acts as a futile cycle at high temperature
Microbiology, 2017Co-Authors: Theresa Kouril, Johann J Eicher, Bettina Siebers, Jacky L SnoepAbstract:In (hyper)thermophilic organisms metabolic processes have to be adapted to function optimally at high temperature. We compared the gluconeogenic conversion of 3-Phosphoglycerate via 1,3-bisPhosphoglycerate to glyceraldehyde-3-phosphate at 30 °C and at 70 °C. At 30 °C it was possible to produce 1,3-bisPhosphoglycerate from 3-Phosphoglycerate with Phosphoglycerate Kinase, but at 70 °C, 1,3-bisPhosphoglycerate was dephosphorylated rapidly to 3-Phosphoglycerate, effectively turning the Phosphoglycerate Kinase into a futile cycle. When Phosphoglycerate Kinase was incubated together with glyceraldehyde 3-phosphate dehydrogenase it was possible to convert 3-Phosphoglycerate to glyceraldehyde 3-phosphate, both at 30 °C and at 70 °C, however, at 70 °C only low concentrations of product were observed due to thermal instability of glyceraldehyde 3-phosphate. Thus, thermolabile intermediates challenge central metabolic reactions and require special adaptation strategies for life at high temperature.
Salvatore Dimauro - One of the best experts on this subject based on the ideXlab platform.
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myopathy and parkinsonism in Phosphoglycerate Kinase deficiency
Muscle & Nerve, 2010Co-Authors: Evangelia Sotiriou, Paul Greene, Sindu Krishna, Michio Hirano, Salvatore DimauroAbstract:A 25-year-old man with exertional myoglobinuria had no evidence of hemolytic anemia, but he had severe parkinsonism that was responsive to levodopa. Phosphoglycerate Kinase (PGK) activity was markedly decreased in muscle, and molecular analysis of the PGK1 gene identified the p.T378P mutation that was recently reported in a patient with isolated myopathy. This case reinforces the concept that PGK deficiency is a clinically heterogeneous disorder and raises the question of a relationship between PGK deficiency and idiopathic juvenile Parkinson disease. Muscle Nerve, 2010
Natalia K. Nagradova - One of the best experts on this subject based on the ideXlab platform.
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Interaction between d-glyceraldehyde-3-phosphate dehydrogenase and 3-Phosphoglycerate Kinase and its functional consequences
FEBS Letters, 1992Co-Authors: Natalia A. Khoroshilova, Vladimir I. Muronetz, Natalia K. NagradovaAbstract:Abstract E. Coli d -glyceraldehyde-3-phosphate dehydrogenase covalently bound to Sepharose was shown to form a complex with soluble E. coli 3-Phosphoglycerate Kinase with a stoichiometry of 1.77±0.61 Kinase molecules per tetramer of the dehydrogenase and an apparent Kd of 1.03±0.68μM (10 mM sodium phosphate, 0.15 M NaCl). No interaction was detected between E. coli d -glyceraldehyde-3-phosphate dehydrogenase and rabbit muscle 3-Phosphoglycerate Kinase. The species-specificity of the bienzyme association made it possible to develop a kinetic approach to demonstrate the functionally significant interaction between E. coli d -glyceraldehyde-3-phosphate dehydrogenase and E. coli 3-Phosphoglycerate Kinase, which consists of an increase in steady-state rate of the coupled reaction.