Muddassar Zafar

Abstract The current study highlights the effect of mutagenesis on endoglucanase B activity of indigenous strain of Aspergillus niger and its heterologous expression studies in the pET28a+ vector. The physical and chemical mutagens were employed to incorporate mutations in A. niger. For determination of mutations, mRNA was isolated followed by cDNA synthesis and cellulase gene was amplified, purified and sequenced both from native and mutant A. niger.

2. Results and Discussion 2.1. Strain Identification and Culturing The novel strain that was obtained for the maximum production of lipase was Aspergillus niger. It was examined under a light microscope and identified by its specific growth pattern. The mature fungal surface appear black in color, and these fungi exist in nature as heterotrophs, so they were provided with all the important nutrients required for growth on potato dextrose agar media [29].