Abstract
We developed a transformation system for Aspergillus oryzae using the Aspergillus nidulans sC gene encoding ATP sulfurylase as a selectable marker. The sC- mutants can be readily isolated by positive selection for selenate resistance, thereby the niaD- mutant strain of A. oryzae was bestowed with the sC- mutation. Transformation of the A. oryzae host (niaD-, sC-) with the plasmid carrying A. nidulans sC gave random and multi-copy integrants, while that with the A. oryzae niaD-carrying plasmid occurred mainly by single-copy and homologous integration events (more than 50% frequency), indicating that with this transformation system, the transformation marker could be selected according to the integration pattern one desires.
