J. Inst. Brew. 114(2), [83][84][85][86][87][88][89][90][91][92][93][94][95][96] 2008 Plasmid stability of the recombinant Saccharomyces cerevisiae C468/pGAC9 (ATCC 20690) strain harboring a pGAC9 plasmid with glucoamylase genes has been investigated in shake flasks and in a bioreactor system using various compositions of media containing glucose or starch as the main carbon and energy source. The medium composition affected both the growth characteristics of S. cerevisiae and stability of the plasmid. Superior plasmid stability was obtained in yeast minimal medium and in complex medium with 0.5 to 2% D-glucose. Plasmid stability of 92% was obtained in complex medium with 2% D-glucose yielding 48 units of glucoamylase/g of cells compared to 54% plasmid stability achieved with 2% soluble starch, which yielded 23 units of glucoamylase/g of cells. The plasmid stability increased at high growth rates and decreased with increasing starch concentration in the complex media as compared to glucose medium. The kinetic characteristics of biomass and glucoamylase production were investigated, and a growth kinetic model was used to interpret the experimental results.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.