Partial purification and some regulatory properties of pyruvate kinase from germinating castor bean endosperm
- 1 August 1976
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant and Cell Physiology
- Vol. 17 (4) , 653-660
- https://doi.org/10.1093/oxfordjournals.pcp.a075321
Abstract
The activity of pyruvate kinase in castor bean endosperm was found to increase rapidly from the 3rd to 4th day of germination. The crude enzyme is very labile, but, was stabilized by adding Mg2+ with a high concentration of ethyleneglycol or glycerol. The enzyme thus stabilized was partially purified about 150-fold by fractionation with ammonium sulfate, and chromatography with DEAE-cellulose and Sephadex G-150. The enzyme showed normal Michaelis-Menten kinetics for both substrates; Km for PEP and ADP were 0.058 mM and 0.13 mM, respectively. Optimum pH was near 6.5. The effects of many kinds of amino acids, intermediates of glycolysis, and the tricarboxylic acid cycle on the activity of the enzyme were tested. ATP was found to inhibit and α-ketoglutarate to activate enzymatic activity.This publication has 3 references indexed in Scilit:
- 7 PhosphofructokinasePublished by Elsevier ,1973
- Gluconeogenesis from Amino Acids in Germinating Castor Bean Endosperm and its Role in Transport to the EmbryoPlant Physiology, 1967
- PROTEIN MEASUREMENT WITH THE FOLIN PHENOL REAGENTJournal of Biological Chemistry, 1951