Open AccessPurification and characterization of a novel exopolygalacturonase from Fusarium oxysporum f.sp. lycopersici
Author(s) -
Garcıća Maceira Fé I,
Pietro Antonio,
Roncero M.Isabel G
Publication year - 1997
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.1574-6968.1997.tb12621.x
Subject(s) - isoelectric point , fusarium oxysporum , chemistry , cationic polymerization , hydrolysis , enzyme , isoelectric focusing , biochemistry , chromatography , biology , polymer chemistry , botany
A novel exopolygalacturonase (EC 3.2.1.15) was purified to apparent homogeneity from cultures of Fusarium oxysporum f.sp. lycopersici on synthetic medium supplemented with polygalacturonic acid, using two steps of purification: preparative isoelectric focusing and cationic exchange chromatography. The enzyme designated PG3 had an apparent M r of 63 000±3000 Da upon SDS‐PAGE and a p I of 7.0. PG3 was active within a broad range of pH from 3.5 to 9. The temperature optimum was 55°C. PG3 hydrolyzed polygalacturonic acid in an exo‐manner, as demonstrated by analysis of degradation products. The enzyme was N ‐glycosylated. The production of PG3 was constitutive at low levels, and synthesis was increased following induction by PGA and partially repressed by glucose.