Isoenzyme of pyruvate kinase in proplastids from developing castor bean endosperm.
نویسندگان
چکیده
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.
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ورودعنوان ژورنال:
- Plant physiology
دوره 61 6 شماره
صفحات -
تاریخ انتشار 1978