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. 1980 Feb;65(2):314–318. doi: 10.1104/pp.65.2.314

Pyruvate Dehydrogenase Complex from Germinating Castor Bean Endosperm 1

Barbara J Rapp 1, Douglas D Randall 1,2
PMCID: PMC440317  PMID: 16661180

Abstract

Subcellular organelles from castor bean (Ricinus communis) endosperm were isolated on discontinuous sucrose gradients from germinating seeds which were 1 to 7 days postimbibition. Marker enzyme activities of the organelles were measured (fumarase, catalase, and triose phosphate isomerase) and the homogeneity of the organelle fractions was examined by electron microscopy. Pyruvate dehydrogenase complex activity was measured only in the mitochondrial fraction and attempts to activate or release the enzyme from the proplastid were not successful. A pathway is proposed for the most efficient use of endosperm carbon for de novo fatty acid biosynthesis that does not require the presence of the pyruvate dehydrogenase complex in the proplastid to provide acetyl-coenzymeA.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Benedict C. R. The presence of ribulose 1,5-diphosphate carboxylase in the nonphotosynthetic endosperm of germinating castor beans. Plant Physiol. 1973 Apr;51(4):755–759. doi: 10.1104/pp.51.4.755. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Cooper T. G., Beevers H. Beta oxidation in glyoxysomes from castor bean endosperm. J Biol Chem. 1969 Jul 10;244(13):3514–3520. [PubMed] [Google Scholar]
  3. Donaldson R. P. Membrane lipid metabolism in germinating castor bean endosperm. Plant Physiol. 1976 Apr;57(4):510–515. doi: 10.1104/pp.57.4.510. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hutton D., Stumpf P. K. Fat Metabolism in Higher Plants. XXXVII. Characterization of the beta-Oxidation Systems From Maturing and Germinating Castor Bean Seeds. Plant Physiol. 1969 Apr;44(4):508–516. doi: 10.1104/pp.44.4.508. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  6. Miflin B. J., Beevers H. Isolation of intact plastids from a range of plant tissues. Plant Physiol. 1974 Jun;53(6):870–874. doi: 10.1104/pp.53.6.870. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Nishimura M., Beevers H. Isolation of intact plastids from protoplasts from castor bean endosperm. Plant Physiol. 1978 Jul;62(1):40–43. doi: 10.1104/pp.62.1.40. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Randall D. D., Rubin P. M., Fenko M. Plant pyruvate dehydrogenase complex purification, characterization and regulation by metabolites and phosphorylation. Biochim Biophys Acta. 1977 Dec 8;485(2):336–349. doi: 10.1016/0005-2744(77)90169-3. [DOI] [PubMed] [Google Scholar]
  9. Reid E. E., Lyttle C. R., Canvin D. T., Dennis D. T. Pyruvate dehydrogenase complex activity in proplastids and mitochondria of developing castor bean endosperm. Biochem Biophys Res Commun. 1975 Jan 6;62(1):42–47. doi: 10.1016/s0006-291x(75)80402-5. [DOI] [PubMed] [Google Scholar]
  10. Rubin P. M., Randall D. D. Purification and characterization of pyruvate dehydrogenase complex from borccoli floral buds. Arch Biochem Biophys. 1977 Jan 30;178(2):342–349. doi: 10.1016/0003-9861(77)90202-8. [DOI] [PubMed] [Google Scholar]
  11. Simcox P. D., Reid E. E., Canvin D. T., Dennis D. T. Enzymes of the Glycolytic and Pentose Phosphate Pathways in Proplastids from the Developing Endosperm of Ricinus communis L. Plant Physiol. 1977 Jun;59(6):1128–1132. doi: 10.1104/pp.59.6.1128. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Tolbert N. E. Isolation of subcellular organelles of metabolism on isopycnic sucrose gradients. Methods Enzymol. 1974;31:734–746. doi: 10.1016/0076-6879(74)31077-4. [DOI] [PubMed] [Google Scholar]
  13. Vick B., Beevers H. Fatty Acid synthesis in endosperm of young castor bean seedlings. Plant Physiol. 1978 Aug;62(2):173–178. doi: 10.1104/pp.62.2.173. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Vigil E. L. Cytochemical and developmental changes in microbodies (glyoxysomes) and related organelles of castor bean endosperm. J Cell Biol. 1970 Sep;46(3):435–454. doi: 10.1083/jcb.46.3.435. [DOI] [PMC free article] [PubMed] [Google Scholar]

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