title: Isoenzyme of pyruvate kinase in proplastids from developing castor bean endosperm.
abstract: Proplastids from developing castor bean (Ricinus communis) endosperm have a pyruvate kinase activity which is extremely unstable on isolation from the organelle. It can be stabilized by 20 mm 2-mercaptoethanol in 20% ethylene glycol. In contrast the soluble pyruvate kinase is stable at 60 C for 10 minutes. The two activities have different pH optima. The soluble and the proplastid activities are eluted from a diethylaminoethyl-Sephadex A-25 sievorptive column at different ionic strengths.
authors: Department of Biology, Queen's University, Kingston, Ontario Canada K7L 3N6.
authors: V
authors: V
authors: De Luca
authors: D T
authors: DT
authors: Dennis