Abstract
Soybean (Glycine max [L.] Merr.) root nodules contain the enzymes of the ascorbate-glutathione pathway to minimize oxidative damage. In the present study, fractionation and immunocytochemistry were used to determine the subcellular location of the enzymes of this pathway. All four enzymes (ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase) were present in the soluble fraction from nodule plant cells and in isolated mitochondria. No activity was detected in peroxisomes. Bacteroids contained glutathione reductase but not the other enzymes of this pathway. Immunogold localization indicated that ascorbate peroxidase was present in the cytosol of infected and uninfected cells but not in the peribacteroid space. Results of immunogold and immunofluorescence studies indicated that monodehydroascorbate reductase was located primarily in the cell wall, suggesting that ascorbate regeneration in the cytoplasm may proceed primarily through the action of dehydroascorbate reductase. The possible roles of monodehydroascorbate reductase in cell wall metabolism are discussed.
Full Text
The Full Text of this article is available as a PDF (2.3 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Becana M., Klucas R. V. Transition metals in legume root nodules: iron-dependent free radical production increases during nodule senescence. Proc Natl Acad Sci U S A. 1992 Oct 1;89(19):8958–8962. doi: 10.1073/pnas.89.19.8958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Dalton D. A., Hanus F. J., Russell S. A., Evans H. J. Purification, properties, and distribution of ascorbate peroxidase in legume root nodules. Plant Physiol. 1987 Apr;83(4):789–794. doi: 10.1104/pp.83.4.789. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dalton D. A., Langeberg L., Robbins M. Purification and characterization of monodehydroascorbate reductase from soybean root nodules. Arch Biochem Biophys. 1992 Jan;292(1):281–286. doi: 10.1016/0003-9861(92)90080-g. [DOI] [PubMed] [Google Scholar]
- Groden D., Beck E. H2O2 destruction by ascorbate-dependent systems from chloroplasts. Biochim Biophys Acta. 1979 Jun 5;546(3):426–435. doi: 10.1016/0005-2728(79)90078-1. [DOI] [PubMed] [Google Scholar]
- Hanks J. F., Tolbert N. E., Schubert K. R. Localization of enzymes of ureide biosynthesis in peroxisomes and microsomes of nodules. Plant Physiol. 1981 Jul;68(1):65–69. doi: 10.1104/pp.68.1.65. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hossain M. A., Asada K. Monodehydroascorbate reductase from cucumber is a flavin adenine dinucleotide enzyme. J Biol Chem. 1985 Oct 25;260(24):12920–12926. [PubMed] [Google Scholar]
- Ko M. P., Huang P. Y., Huang J. S., Barker K. R. The occurrence of phytoferritin and its relationship to effectiveness of soybean nodules. Plant Physiol. 1987 Feb;83(2):299–305. doi: 10.1104/pp.83.2.299. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schuller K. A., Day D. A., Gibson A. H., Gresshoff P. M. Enzymes of ammonia assimilation and ureide biosynthesis in soybean nodules: effect of nitrate. Plant Physiol. 1986 Mar;80(3):646–650. doi: 10.1104/pp.80.3.646. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ye Z. H., Varner J. E. Tissue-Specific Expression of Cell Wall Proteins in Developing Soybean Tissues. Plant Cell. 1991 Jan;3(1):23–37. doi: 10.1105/tpc.3.1.23. [DOI] [PMC free article] [PubMed] [Google Scholar]