단백질 고생산 야생형 효모 균주 선별 및 무작위 돌연변이를 통한 단백질 함량 증대

Abstract

Protein can be provided by cultivating various microbes, which contain more than 30% protein content by cell dry weight. This study compared intracellular protein concentrations of various wild-type yeasts from different sources to select the best yeast strain with high protein concentration. Among them, Saccharomyces cerevisiae KCCM 34709, used for molasses fermentation, exhibited 4.1-fold higher protein concentration than a laboratory yeast strain, S. cerevisiae D452-2. In this study, an approach consisting of random mutagenesis coupled with the Bradford protein assay-based screening method was applied to enhance the S. cerevisiae KCCM 34709 protein content. Among 1,000 mutants, the #180 mutant strain produced 5,041±519 mg/L total amino acid in 48 h, which was 31% higher than the parental S. cerevisiae KCCM 34709 strain. These results demonstrate that the #180 mutant strain can be an attractive cell factory for animal-free protein production.