Production, purification and characterization of an exo-polygalacturonase from Penicillium janthinellum sw09

摘要

A soil isolate, Penicillium janthinellum sw09 has been found to produce significant amounts of an extracellular pectinase subsequently characterized as exo-polygalacturonase (exo-PG). By optimizing growth conditions, P. janthinellum sw09 produced high amount of exo-PG (16.54 units/mL). The crude enzyme was purified by gel filtration chromatography and two exo-PG activity peaks (designated as PGI and PGII) were revealed. On SDS-PAGE analysis, purified PGII using DEAE-Sepharose FF column, was found to be a single band with a molecular mass of 66.2 kDa. The purified PGII exhibited maximal activity at the temperature of 45 o C and pH 5.0. The stability profiles show that PGII is more stable in the pH range of 4.0-8.0 and below 60 o C. The K m and V max for the enzyme was 1.74 mg/mL and 18.08 ??mol/ (mLa?￠min), respectively. Due to this enzymatic characterization, this pectinase is an attractive candidate for applications in degradation of pectin.