토끼 대퇴근육에서 부분정제한 M4-LDH의 특성에 관한 연구

Abstract

1. The M.-LDH was partially purified approximately 14 fold of its activity from the thigh muscle of rabbits by means of salting-out with ammonium sulfate and of DEAE-cellulose column chromatography. 2. The activity of the M.-LDH was inhibited by 0.02M pyruvate to 22% of the original activity. 3. Sulfide ions. when added to the reacion system using lactate as the substrate. accentuated the inhibition already brought by pyruvate alone. 4. Cysteine. on the other hand. when treated similarly as sulfide ions. decreased the magnitude of pyruvate inhibition in its lower range of concentration. but showed its own inhibitory effect without regard to the pyruvate inhibition in its higher range of concentration. 5. When lactate was used as substrate. both sulfide ions and cysteine played as a non-competitive inhibitors. 6. When pyruvate was used as substrate. cysteine showed an apparently allosteric effect. while sulfide ions showed no particular effect different from pyruvate induction itself.