A homologous transformation system has been developed for Aspergillus oryzae industrial strains using the A. oryzae acetamidase-encoding gene (amdS) as a dominant selectable marker. Although the transformation efficiency is relatively low (0.4-1 transformants per μg DNA), the transformants contained significantly high copy numbers of the plasmid integrated into the genome. In addition, the promoter of the amdS gene was replaced by the strong expression promoter of the α-amylase-encoding gene (amyB) from A. oryzae, thereby enhancing the selection of the transformants.
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology