Skip to main content
Plant Physiology logoLink to Plant Physiology
. 1995 Nov;109(3):847–851. doi: 10.1104/pp.109.3.847

A Specific Ascorbate Free Radical Reductase Isozyme Participates in the Regeneration of Ascorbate for Scavenging Toxic Oxygen Species in Potato Tuber Mitochondria.

S De Leonardis 1, G De Lorenzo 1, G Borraccino 1, S Dipierro 1
PMCID: PMC161385  PMID: 12228637

Abstract

Ascorbate free radical (AFR) reductase from isolated potato tuber (Solanum tuberosum L.) mitochondria was studied. The enzyme was purified to homogeneity and its physico-chemical and kinetic properties were compared to those of the cytosolic enzyme. The molecular mass of the mitochondrial enzyme was about 54 kD, whereas that of the cytosolic enzyme was about 42 kD. The Km values of mitochondrial AFR reductase for NADH, NADPH, and AFR were higher than those of the cytosolic enzyme. Moreover, the mitochondrial enzyme proved to be less sensitive to inhibition by sulfhydryl reagents. It was concluded that the ascorbate involved in the scavenging of toxic oxygen species in potato tuber mitochondria is regenerated via the ascorbate-glutathione pathway, in which a specific AFR reductase isozyme participates.

Full Text

The Full Text of this article is available as a PDF (1.5 MB).

Selected References

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

  1. Cadenas E., Boveris A. Enhancement of hydrogen peroxide formation by protophores and ionophores in antimycin-supplemented mitochondria. Biochem J. 1980 Apr 15;188(1):31–37. doi: 10.1042/bj1880031. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Dalton D. A., Baird L. M., Langeberg L., Taugher C. Y., Anyan W. R., Vance C. P., Sarath G. Subcellular Localization of Oxygen Defense Enzymes in Soybean (Glycine max [L.] Merr.) Root Nodules. Plant Physiol. 1993 Jun;102(2):481–489. doi: 10.1104/pp.102.2.481. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Douce R., Christensen E. L., Bonner W. D., Jr Preparation of intaintact plant mitochondria. Biochim Biophys Acta. 1972 Aug 17;275(2):148–160. doi: 10.1016/0005-2728(72)90035-7. [DOI] [PubMed] [Google Scholar]
  4. Droillard M. J., Paulin A. Isozymes of Superoxide Dismutase in Mitochondria and Peroxisomes Isolated from Petals of Carnation (Dianthus caryophyllus) during Senescence. Plant Physiol. 1990 Nov;94(3):1187–1192. doi: 10.1104/pp.94.3.1187. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Halliwell B., Gutteridge J. M. Oxygen toxicity, oxygen radicals, transition metals and disease. Biochem J. 1984 Apr 1;219(1):1–14. doi: 10.1042/bj2190001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Halliwell B. Production of superoxide, hydrogen peroxide and hydroxyl radicals by phagocytic cells: a cause of chronic inflammatory disease? Cell Biol Int Rep. 1982 Jun;6(6):529–542. doi: 10.1016/0309-1651(82)90175-8. [DOI] [PubMed] [Google Scholar]
  7. Kanematsu S., Asada K. Chloroplast and cytosol isozymes of CuZn-superoxide dismutase: their characteristic amino acid sequences. Free Radic Res Commun. 1991;12-13 Pt 1:383–390. doi: 10.3109/10715769109145808. [DOI] [PubMed] [Google Scholar]
  8. Morrissey J. H. Silver stain for proteins in polyacrylamide gels: a modified procedure with enhanced uniform sensitivity. Anal Biochem. 1981 Nov 1;117(2):307–310. doi: 10.1016/0003-2697(81)90783-1. [DOI] [PubMed] [Google Scholar]
  9. Nohl H., Jordan W. The mitochondrial site of superoxide formation. Biochem Biophys Res Commun. 1986 Jul 31;138(2):533–539. doi: 10.1016/s0006-291x(86)80529-0. [DOI] [PubMed] [Google Scholar]
  10. Oba K., Ishikawa S., Nishikawa M., Mizuno H., Yamamoto T. Purification and properties of L-galactono-gamma-lactone dehydrogenase, a key enzyme for ascorbic acid biosynthesis, from sweet potato roots. J Biochem. 1995 Jan;117(1):120–124. doi: 10.1093/oxfordjournals.jbchem.a124697. [DOI] [PubMed] [Google Scholar]
  11. Overbaugh J. M., Fall R. Characterization of a Selenium-Independent Glutathione Peroxidase From Euglena gracilis. Plant Physiol. 1985 Feb;77(2):437–442. doi: 10.1104/pp.77.2.437. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Streller S., Krömer S., Wingsle G. Isolation and purification of mitochondrial Mn-superoxide dismutase from the gymnosperm Pinus sylvestris L. Plant Cell Physiol. 1994 Sep;35(6):859–867. [PubMed] [Google Scholar]
  13. Washko P. W., Wang Y., Levine M. Ascorbic acid recycling in human neutrophils. J Biol Chem. 1993 Jul 25;268(21):15531–15535. [PubMed] [Google Scholar]
  14. Zhu D., Scandalios J. G. Maize mitochondrial manganese superoxide dismutases are encoded by a differentially expressed multigene family. Proc Natl Acad Sci U S A. 1993 Oct 15;90(20):9310–9314. doi: 10.1073/pnas.90.20.9310. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES