Pathogenesis-Related Proteins of Tomato
Open Access
- 1 May 1988
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 87 (1) , 58-63
- https://doi.org/10.1104/pp.87.1.58
Abstract
An endoproteinase induced by citrus exocortis viroid has been purified from tomato (Lycopersicon esculentum Mill, cv “Rutgers”) leaves. The proteinase corresponds to one of the major pathogenesis-related proteins of tomato plants and was designated proteinase P-69 as it has a molecular weight of 69,000 to 70,000. The proteinase was purified in four steps: (NH4)2SO4 fractionation, chromatography on Bio-Gel P-60, DEAE-Sepharose chromatography, and casein-Sepharose affinity chromatography. The proteinase had a pH optimum of 8.5 to 9.0 when assayed with either fluorescein thiocarbamoyl derivative (FTC)-casein or FTC-ribulose 1,5-bisphosphate carboxylase/oxygenase as substrates. The proteinase activity was inhibited by pCMB and strongly activated by calcium and magnesium ions as well as by DTT. When analyzed by electrofocusing, the activity showed a pI around 9.0.This publication has 20 references indexed in Scilit:
- A tobacco mosaic virus-induced tobacco protein is homologous to the sweet-tasting protein thaumatinNature, 1986
- Induction of Pathogenesis-Related Proteins in Tobacco LeavesPlant Physiology, 1986
- Synthesis of pathogenesis-related proteins in tobacco is regulated at the level of mRNA accumulation and occurs on membrane-bound polysomesProceedings of the National Academy of Sciences, 1985
- Source of Endoproteolytic Activity Associated with Purified Ribulose Bisphosphate CarboxylasePlant Physiology, 1984
- Cell Walls of Phaseolus vulgaris Leaves Contain the Azocoll-Digesting ProteinasePlant Physiology, 1983
- A releationship between protein-degradation rates in vivo, isoelectric points, and molecular weights obtained by using density labellingBiochemical Journal, 1979
- Hydrolytic Enzymes in the Central Vacuole of Plant CellsPlant Physiology, 1979
- A Rapid and Sensitive Method for the Quantitation of Microgram Quantities of Protein Utilizing the Principle of Protein-Dye BindingAnalytical Biochemistry, 1976
- A statistical analysis of the relationship between degradative rates and molecular weights of proteinsArchives of Biochemistry and Biophysics, 1975
- Physical properties of a minimal infectious RNA (viroid) associated with the exocortis diseaseVirology, 1975