Isoenzyme of Pyruvate Kinase in Proplastids from Developing Castor Bean Endosperm
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چکیده
منابع مشابه
Isoenzyme of pyruvate kinase in proplastids from developing castor bean endosperm.
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 ar...
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Cytosolic pyruvate kinase from endosperm of germinating castor beans (Ricinus communis L.; cv Hale) has been purified 3100-fold to apparent homogeneity and a final specific activity of 203 micromole pyruvate produced/minute per milligram protein. Purification steps included: heat treatment, polyethylene glycol fractionation, Q-Sepharose, ADP-agarose, Mono-Q and Phenyl Superose chromatography. N...
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Vacuoles were prepared from endosperm tissue of 4-day-old castor bean seedlings (Ricinus communis var. Hale) and purified on a stepped sucrose gradient. It was shown by assays of marker enzymes that there was only trace contamination of the final preparation by other organelles (mitochondria, glyoxysomes, nuclei, spherosomes, and plastids) and by cytoplasmic components. Hydrolytic enzymes (acid...
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Quinolinic acid phosphoribosyltransf erase was purified WI-fold from the endosperm of etiolated seedlings of Ricinus communis L. Sodium dodecyl sulfate disc gel electrophoresis indicated that the enzyme was homogeneous but on analytical disc gel electrophoresis at pH 7.0 and 8.3 the isolated native protein exhibited three closely migrating bands. The three proteins were of the same molecular we...
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Subceliular organelles from castor bean (Ricuns commnwuis) endosperm were isolated on discontinuous sucrose gradients from germinating seeds which were 1 to 7 days postbit o. Marker enzyme activities of the organeUes were measured (fumarase, catalase, and triose phosphate isomerase) and the homogeneity of the organelle fractions was examined by electron microscopy. Pyrumate dehydrogenase comple...
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ژورنال
عنوان ژورنال: Plant Physiology
سال: 1978
ISSN: 0032-0889,1532-2548
DOI: 10.1104/pp.61.6.1037