Pectin methylesterase from Botrytis cinerea : physiological, biochemical and immunochemical studies

Pectin methylesterase (PME) was purified from the supernatant of Botrytis cinerea strain Bd90. SDS-PAGE showed a single band at 42 kDa, but this band corresponded to two distinct isoforms observed by IEF-PAGE at pl values of 7.0 and 7.4. PME was produced during the exponential phase of fungal growth and independently of the carbon source. Unlike other pectinases of B. cinerea, which are polymorphic, no differences were observed between the PME profiles of 25 strains of different origins. Polyclonal antibodies were raised against purified PME from B. cinerea, and immunochemical comparisons with PMEs from Erwinia chrysanthemi, Vigna radiata and Glycine max showed the presence of common epitopes between these different enzymes.