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. 1973 Mar;51(3):448–453. doi: 10.1104/pp.51.3.448

Multiple Forms of Plant Phosphoenolpyruvate Carboxylase Associated with Different Metabolic Pathways 1

Irwin P Ting a, C B Osmond b
PMCID: PMC366285  PMID: 16658349

Abstract

The physical and kinetic properties of multiple forms of phosphoenolpyruvate carboxylase were studied in leaves of C4 and C3 species, their F1 and F3 hybrids, in greening maize leaves, in Crassulacean acid metabolism plants, and in nongreen root tissues. Four different forms are suggested: a C4 photosynthetic phosphoenolpyruvate carboxylase with high Km for phosphoenolpyruvate (∼0.59 mm), Km Mg (∼0.5 mm), and Vmax (∼29 micromoles per minute per milligram of chlorophyll); a C3 photosynthetic phosphoenolpyruvate carboxylase with low Km for phosphoenolpyruvate (∼0.14 mm), Km for Mg (∼0.097 mm), and Vmax (1.5); a Crassulacean acid metabolism type with low Km for phosphoenolpyruvate (0.14 mm), and high Vmax (14 micromoles per minute per milligram of chlorophyll); and a nongreen or nonautotrophic type with low Km for phosphoenolpyruvate, Km for Mg, and low Vmax. In closely related species or within species, the types can be differentiated by anion exchange column chromatography. Each of the four forms is associated with a different metabolic pathway: the phosphoenolpyruvate carboxylase of C4 species for malate generation as a photosynthetic intermediate, the phosphoenolpyruvate carboxylase of C3 species in malate generation as a photosynthetic product, the phosphoenolpyruvate carboxylase of Crassulacean acid metabolism species in malate generation as a CO2 donor for photosynthesis during the subsequent light period, and a nongreen or root type producing malate for ionic balance and reduced nicotinamide adenine dinucleotide phosphate generation. The data in this paper in conjunction with published information support the notion of different molecular forms of a protein functioning in different metabolic pathways which have common enzymic steps.

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Selected References

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

  1. Anderson L. E., Pacold I. Chloroplast and Cytoplasmic Enzymes: IV. Pea Leaf Fructose 1,6-Diphosphate Aldolases. Plant Physiol. 1972 Mar;49(3):393–397. doi: 10.1104/pp.49.3.393. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. BASSHAM J. A., BENSON A. A., CALVIN M. The path of carbon in photosynthesis. J Biol Chem. 1950 Aug;185(2):781–787. [PubMed] [Google Scholar]
  3. Rocha V., Ting I. P. Malate dehydrogenases of leaf tissue from Spinacia oleracea: properties of three isoenzymes. Arch Biochem Biophys. 1971 Nov;147(1):114–122. doi: 10.1016/0003-9861(71)90316-x. [DOI] [PubMed] [Google Scholar]
  4. Smith T. E. Partial purification and characteristics of potato phosphoenolpyruvate carboxylase. Arch Biochem Biophys. 1968 Apr;125(1):178–188. doi: 10.1016/0003-9861(68)90653-x. [DOI] [PubMed] [Google Scholar]
  5. Ting I. P. CO(2) Metabolism in Corn Roots. III. Inhibition of P-enolpyruvate Carboxylase by l-malate. Plant Physiol. 1968 Dec;43(12):1919–1924. doi: 10.1104/pp.43.12.1919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Ting I. P., Osmond C. B. Photosynthetic phosphoenolpyruvate carboxylases: characteristics of alloenzymes from leaves of c(3) and c(1) plants. Plant Physiol. 1973 Mar;51(3):439–447. doi: 10.1104/pp.51.3.439. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Ting I. P., Rocha V. NADP-specific malate dehydrogenase of green spinach leaf tissue. Arch Biochem Biophys. 1971 Nov;147(1):156–164. doi: 10.1016/0003-9861(71)90322-5. [DOI] [PubMed] [Google Scholar]
  8. WALKER D. A. Physiological studies on acid metabolism. 4. Phosphoenolpyruvic carboxylase activity in extracts of Crassulacean plants. Biochem J. 1957 Sep;67(1):73–79. doi: 10.1042/bj0670073. [DOI] [PMC free article] [PubMed] [Google Scholar]

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