Construction of a Secretory Expression Vector Producing an $\alpha$-Amylase of Yeast, Schwanniomyces occidentalis in Saccharomyces

Abstract

Using a modified yeast secretory expression vector, $\alpha$-amylase of Schwanniomyces occidentalis was produced from Saccharomyces cerevisiae. The expression vector contains the a-amylase gene (AMY) harboring its own promoter without the regulatory region and the adenine base at the -3 position from the ATG start codon, its own signal sequence, CYC1 transcription terminator, and SV40 enhancer. The expressed $\alpha$-amylase activity from cells carrying the plasmid was approximately 26 times higher than that from the cells harboring an unmodified plasmid. When Saccharomyces diastaticus was transformed with this modified vector, a 2.5 times higher level of amylolytic activity than that from Sch. occidentalis was observed.

Keywords

• Yeast secretory expression vector;
• Schwanniomyces occidentalis $\alpha$-amylase gene;
• Saccharomyces cerevisiae;
• Saccharomyces diastaticus