Partially purified polygalacturonase from Aspergillus niger (SA6)

Abstract

Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger) (SA6), partially purified and characterized. The PG showed two bands on SDS-PAGE suggesting an “endo and exo PG with apparent molecular weights of 35 and 40 KDa, respectively. It was purified 9-fold with a yield of 0.18% and specific activity of 246 μmole/ml/mg. The K_M and V_max of the enzyme were 2.74 mg/ml and 0.78 μmole/min/mg, respectively. The optimum temperature and optimum pH of the enzyme were 40°C and 4.5, respectively. The PG was found to be more stable to temperature changes than to pH changes.

Keyword: Polygalacturonase, Aspergillus niger