Oligogalacturonate hydrolase with unique substrate preference from the pulp of parsley roots

Abstract

The main form of pectate hydrolases in the cell wall of parsley roots showed a unique substrate preference of a plant exopolygalacturonase because it clearly preferred the substrates with degree of polymerization about 10. This form was separated from the others, purified and characterized. Enzyme exhibited sharp pH optimum corresponding to pH 4.7, molecular mass 53.5 kDa, and isoelectric point 5.3. It was stable at 50°C in 2-h assay and had optimum of temperature at 60°C (activation energy being 37.0 kJ/mol). The interaction with concanavalin A indicated the glycosylation of enzyme. Substrates were cleaved from the non-reducing end.