The course of pectin degradation by polygalacturonases from Fusarium oxysporum f. sp. radicis lycopersici.

The production of polygalacturonases from Fusarium oxysporum f. sp. radicis lycopersici (FORL) occurred sequentially, and endo- and exo-polygalacturonases (PG) predominated at different times during growth. At first FORL produced a PG which did not release monomers from pectins and was unable to hydrolyse dimers and trimers. Later a complex was produced in which exo-PG seemed to be the predominant activity; the monomer was released rapidly and this activity was able to degrade dimers and trimers.