Skip to main content
NCBI home page
Plant Physiology logoLink to Plant Physiology
. 1979 Feb;63(2):289–293. doi: 10.1104/pp.63.2.289

A Study of Formate Production and Oxidation in Leaf Peroxisomes during Photorespiration

Bernard Grodzinski 1
PMCID: PMC542816  PMID: 16660715

Abstract

When glycolate was metabolized in peroxisomes isolated from leaves of spinach beet (Beta vulgaris L., var. vulgaris) formate was produced. Although the reaction mixture contained glutamate to facilitate conversion of glycolate to glycine, the rate at which H2O2 became “available” during the oxidation of [1-14C]glycolate was sufficient to account for the breakdown of the intermediate [1-14C]glyoxylate to formate (C1 unit) and 14CO2. Under aerobic conditions formate production closely paralleled 14CO2 release from [1-14C]glycolate which was optimal between pH 8.0 and pH 9.0 and was increased 3-fold when the temperature was raised from 25 to 35 C, or when the rate of H2O2 production was increased artificially by addition of an active preparation of fungal glucose oxidase.

When [14C]formate was added to these preparations it was oxidized directly to 14CO2 by the peroxidatic action of peroxisomal catalase; however, the breakdown of formate was slow relative to the rate of formate production. For example, when [14C]formate was generated from [2-14C]glycolate it was not readily oxidized to 14CO2 in these organelles. Because the activity of formate-NAD+ dehydrogenase in cell-free leaf extracts was low compared with that of formyl tetrahydrofolate synthetase it is suggested that most of the formate produced during glycolate oxidation could be metabolized via the one carbon pool and not oxidized directly to CO2.

At 25 C the rate of release of 14CO2 from [2-14C]glycolate in leaf discs was 40 to 50% of the rate from [1-14C]glycolate. Isonicotinyl hydrazide inhibited 14CO2 release from both [1-14C]- and [2-14C]glycolate; but this inhibitor was more effective in blocking 14CO2 release from [2-14C]glycolate. It is argued that the oxidation of the methylene carbon group of glycolate does not occur as a direct consequence of formate (C1 unit) breakdown, but is a product of the further metabolism of formate and glycine, possibly, via serine.

Full text

PDF
289

Selected References

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

  1. Arnon D. I. COPPER ENZYMES IN ISOLATED CHLOROPLASTS. POLYPHENOLOXIDASE IN BETA VULGARIS. Plant Physiol. 1949 Jan;24(1):1–15. doi: 10.1104/pp.24.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Crosti P. Intracellular distribution of 10-formyl tetrahydrofolic acid synthetase in spinach leaves. Ital J Biochem. 1974 Mar-Apr;23(2):72–86. [PubMed] [Google Scholar]
  3. Halliwell B., Butt V. S. Oxidative decarboxylation of glycollate and glyoxylate by leaf peroxisomes. Biochem J. 1974 Feb;138(2):217–224. doi: 10.1042/bj1380217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Halliwell B. Oxidation of formate by peroxisomes and mitochondria from spinach leaves. Biochem J. 1974 Jan;138(1):77–85. doi: 10.1042/bj1380077. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Keilin D., Hartree E. F. Properties of catalase. Catalysis of coupled oxidation of alcohols. Biochem J. 1945;39(4):293–301. [PMC free article] [PubMed] [Google Scholar]
  6. Leek A. E., Halliwell B., Butt V. S. Oxidation of formate and oxalate in peroxisomal preparations from leaves of spinach beet (Beta vulgaris L.). Biochim Biophys Acta. 1972 Dec 29;286(2):299–311. doi: 10.1016/0304-4165(72)90266-8. [DOI] [PubMed] [Google Scholar]
  7. Oshino N., Oshino R., Chance B. The characteristics of the "peroxidatic" reaction of catalase in ethanol oxidation. Biochem J. 1973 Mar;131(3):555–563. doi: 10.1042/bj1310555. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Servaites J. C. Chemical inhibition of the glycolate pathway in soybean leaf cells. Plant Physiol. 1977 Oct;60(4):461–466. doi: 10.1104/pp.60.4.461. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Zelitch I. Comparison of the effectiveness of glycolic Acid and glycine as substrates for photorespiration. Plant Physiol. 1972 Jul;50(1):109–113. doi: 10.1104/pp.50.1.109. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Zelitch I. Increased rate of net photosynthetic carbon dioxide uptake caused by the inhibition of glycolate oxidase. Plant Physiol. 1966 Dec;41(10):1623–1631. doi: 10.1104/pp.41.10.1623. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Zelitch I. Pathways of carbon fixation in green plants. Annu Rev Biochem. 1975;44:123–145. doi: 10.1146/annurev.bi.44.070175.001011. [DOI] [PubMed] [Google Scholar]
  12. Zelitch I. The photooxidation of glyoxylate by envelope-free spinach chloroplasts and its relation to photorespiration. Arch Biochem Biophys. 1972 Jun;150(2):698–707. doi: 10.1016/0003-9861(72)90088-4. [DOI] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES