[Kinetic characteristics of glutamine synthetase from the chloroplasts of pea leaves].
The kinetic properties of glutamine synthetase (EC 6.3.1.2) isolated from pea chloroplasts and purified according to the previously developed procedure have been investigated. The pH optimum for the enzymatic reaction in the presence of Mg2+ and Mn2+ are 7.5-7.6 and 5.5, respectively. The corresponding values of the activation energy per enzyme monomer (Mr = 60 000) are equal to 2900 and 1190 cal/mole. With Mg2+ the values of Km(app.) for NH4+, NH2OH, L-glutamate (+NH4+), L-glutamate (+NH2OH), ATP(+NH4+ and NH2OH) and Mg-ATP (+NH4+ and NH2OH) are 0.64, 17.5, 5.6, 7.0, 1.3 and 0.74 mM, respectively.
D002412:Cations; D002736:Chloroplasts / Q000201:enzymology*; D004789:Enzyme Activation; D007887:Fabaceae / Q000201:enzymology; D005974:Glutamate-Ammonia Ligase / Q000378:metabolism*; D007700:Kinetics; D010944:Plants / Q000201:enzymology*; D010946:Plants, Medicinal
D002412:Cations; D005974:Glutamate-Ammonia Ligase
Kineticheskie kharakteristiki glutaminsintetazy Khloroplastov list'ev gorokha.