6533b839fe1ef96bd12a6d8c
RESEARCH PRODUCT
Studies on the Mechanism of Inhibition by Phosphinothricin of Glutamine Synthetase Isolated from Triticum aestivum L.
Remigius ManderscheidAloysius Wildsubject
chemistry.chemical_classificationOrder of reactionPhysiologySize-exclusion chromatographyPlant ScienceBiologyRate-determining stepIsozymeChloroplastEnzymechemistryBiochemistryGlutamine synthetaseAgronomy and Crop Sciencedescription
Summary The activity of glutamine synthetase (EC 6.3.1.2) isolated from roots and leaves of wheat is strongly inhibited by phosphinothricin. As revealed by gel filtration and kinetic studies the mechanism of inhibition appears to be irreversible. The results indicate that the rate limiting step of the reaction of the inhibitor with the chloroplast glutamine synthetase is not the initial, but the following reaction. However, of root glutamine synthetase the irreversible inhibition follows a second order reaction depending on the concentration of the enzyme and of phosphinothricin and the rate limiting step is the formation of the initial enzyme-inhibitor complex. According to the kinetic data, the glutamine synthetase of the root appears to be more strongly inhibited by phosphinothricin than the chloroplast glutamine synthetase.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1986-04-01 | Journal of Plant Physiology |