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

Abstract

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 μmol/ (mL•min), respectively. Due to this enzymatic characterization, this pectinase is an attractive candidate for applications in degradation of pectin.

Biotechnological potential of an exo‐polygalacturonase of the new strain Penicillium janthinellum VI2R3M: biochemical characterization and clarification of fruit juices

“…In comparison to Penicillium notatum, both enzymes were purified three times, but the PG of P. notatum presented a specific activity of 27Á79 U mg À1 (Amin et al 2017). The relative molecular mass of our enzyme (102Á0 kDa) was higher than the PG of P. janthinellum sw09 of 66Á2 kDa (Ma et al 2016) and exo-PG of Rhizomucor pusillus A13Á36 (Trindade et al 2016) described in the literature. The PGs of different micro-organisms have been reported with molecular weights ranging from 24 to 124 kDa (Gomes et al 2011;Anand et al 2017).…”

“…The value of K m shown by polygalacturonase from P. janthinellum VI2R3M polygalacturonase was greater than of an exo‐PG of P. janthinellum (1·74 mg ml −1 ) described by Ma et al () and an exo‐PG of Penicillium frequentans (0·059 mg ml −1 ) (Anand et al ). However, it was a very close to K m reported for an exo‐PG of A. niger (2·3 mg ml −1 ).…”

“…The higher activity at pH 5·0 is in the range of most fungal pectinases described, which have ideal pHs between 3·0 and 6·0, and which is also the optimum pH for the activity of PG from the fungi P. janthinellum sw09 and Penicillium occitanis (Ma et al ; Tounsi et al ). The pH stability shown in the present study is in agreement with Siddiqui et al (), who observed that the maximum stability of the PG is between pH 4·0 and 5·0; above this there is a decrease in the enzymatic activity.…”

“…Polygalacturonases are classified according to their substrate specificity and the position of the bonds they hydrolyse (Ma et al ). When enzymes of the endo‐polygalacturonase type (endo‐PGs) act on PGA, they liberate oligosaccharides with a low degree of polymerization (tri‐ and tetragalacturonic acids) as the final hydrolysis product, while exo‐polygalacturonase (exo‐PG) releases mainly mono‐ and digalacturonic acid (Tounsi et al ).…”

Penicillium janthinellum: A Potential Producer of Natural Products

“…The other compounds included two benzoic acid derivatives (144 and 145) and eight phenol derivatives (146)(147)(148)(149)(150)(151)(152)(153), with only one new compound (146). Compound 150 exhibited cytotoxicity against multiple cell lines and its mechanism of bioactivity has been investigated, suggesting its potential as an anticancer drug candidate.…”