Comparative analysis of polygalacturonases in isolates of seven species of Fusarium from Pinus pinea

Polygalacturonases (PGs) are important pectolytic enzymes produced by phytopathogenic fungi during the process of infection and colonistation of the host plants. In this work, PGs produced by isolates of seven Fusarium species associated to Pinus pinea have been analysed for: activity, isoform pattern observed by isoelectric focusing endo- or exo-mode of action and their production in culutres growing on pectin and galacturonic acid. Of the seven isolates, those of F. oxysporum and F. moniliforme exhibite high PG activity and the most complex isoform patterns including acidic ones. These isolates were also more efficient in degrading the PG substrate, during which both endo and exo type polygalacturonase activities were detected. It is suggested that these features could be useful to the fungus during infection and colonisation of its host, specially during seed germination and early development.