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Updated: Sep 20, 2026

EPR Monitored Redox Titration of the Cofactors of Saccharomyces cerevisiae Nar1
Published on: November 26, 2014
Characterization and regulation of NADP+-isocitrate dehydrogenase from Saccharopolyspora erythraea
Alejandra Alvarado1, Maria Elena Flores
1Department of Molecular Biology and Biotechnology, Institute for Biomedical Research, National University of Mexico, Mexico, D.F., Mexico.
Abstract:
NADP+-Isocitrate dehydrogenase (ICDH) activity was detected in cell-free extracts of Saccharopolyspora erythraea CA340, an erythromycin producer. Apparent Km values for DL-isocitrate and NADP+ were 0.14 microM and 0.026 microM, respectively. ATP, ADP, GTP, citric acid, oxaloacetate, alpha-ketoglutarate, glyoxalate and glyoxalate plus oxaloacetate, each at 1 mM concentration, caused 50, 20 10, 50, 25, 60, 20 and 50% inhibition of ICDH activity, respectively. Phosphoenolpyruvate, fructose 1,6-diphosphate and pyruvate had no effect. ICDH specific activity profile was growth-associated and activity with dextrose or fructose as sole carbon source, was twice of that obtained with lactose.
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