Open AccessPurification and characterization of an exo‐polygalacturonase from the tomato vascular wilt pathogen Fusarium oxysporum f.sp. lycopersici
Author(s) -
Di Pietro Antonio,
Roncero M. Isabel G.
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08592.x
Subject(s) - pectinase , fusarium oxysporum f.sp. lycopersici , fusarium oxysporum , isoelectric point , isoelectric focusing , pectate lyase , biology , pathogen , pectin lyase , enzyme , biochemistry , fungi imperfecti , hydrolysis , microbiology and biotechnology , fusarium wilt , chemistry , botany
An exo‐polygalacturonase (EC 3.2.1.15) was purified to apparent homogeneity from cultures of Fusarium oxysporum f.sp. lycopersici on synthetic medium supplemented with citrus pectin, using preparative isoelectric focusing. The enzyme, denominated PG2, had an apparent M r of 74000 Da upon SDS‐PAGE. The pI of the main PG2 isoform was 4.5, and pH and temperature optima were 5.0 and 55 °C, respectively. PG2 hydrolyzed polygalacturonic acid in an exo‐manner, as demonstrated by anaysis of degradation products. The enzyme was N‐glycosylated. The N‐terminal amino acid sequence, L‐A‐F‐N‐V‐P‐S‐K‐P‐P, has no identity to other known polygalacturonases.