[Kinetics and regulatory properties of the disulfide reductase enzyme from mouse liver].
Disulfide reductase (DSR) of mice liver supernatant is kinetically demonstrated as associating-dissociating oligomeric protein with positive homotropic cooperativity for the substrate. Cyclic 3',5'-AMP (10(-11)--10(-5) M) activates DSR and increases V, but does not change either [S]0,5, nor nH and does not shift the plot of specific activity versus the enzyme concentration. ATP, GTP, UTP, CTP, protamine, histone, Mg2+, Ca2+, EDTA (but not adenosine, 5'-AMP, 2'3'-AMP, ADP beef serum albumin) activated DSR. The effects of different modifiers are not summed up. Preincubation is essential for the action of the majority of the activators. Heating for 8 minutes at 55 degrees C desensitized completely DSR to all the modifiers without changing its catalytic activity, [S]0,5 and nH values. Possible mechanisms of activation of DSR, especially the involvement of protein kinase, are discussed.
D000818:Animals; D002384:Catalysis; D000242:Cyclic AMP; D004789:Enzyme Activation; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D051379:Mice; D008808:Mice, Inbred CBA; D010088:Oxidoreductases / Q000378:metabolism*
D000242:Cyclic AMP; D010088:Oxidoreductases
Kineticheskie i reguliatornye svoĭstva disul'fidreduktaznogo fermenta iz pecheni myshi