[Temperature dependence of glutaminase activity from the rat brain under hypothermia].
The temperature dependence of the glutaminase activity in rat brain homogenates and at different steps of enzyme purification was studied under normal and hypothermic (20 degrees) conditions. Under normal conditions the enzyme activity shows a complex temperature dependence. Under hypothermic conditions a site with negative temperature dependence appears on the temperature dependence curve. These changes are observed both in homogenates and in enzyme preparations purified 5- and 60-fold. The mechanisms of this effect are discussed. It is assumed that the structural changes in the enzyme molecule are adaptive to low body temperatures.
D000818:Animals; D001921:Brain / Q000201:enzymology*; D003080:Cold Temperature; D005972:Glutaminase / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D051381:Rats; D011919:Rats, Inbred Strains; D013696:Temperature
D005972:Glutaminase
Temperaturnaia zavisimost' aktivnosti glutaminazy iz mozga krysy pri gipotermii.