Hormone-inducible expression and metal affinity chromatography of recombinant proteins in Saccharomyces cerevisiae

An economical method to express recombinant protein in yeast (Saccharomyces cerevisiae) was developed. We combined two principles: Ni(2+)-agarose-based affinity purification of fusion proteins and expression from a cassette regulated by steroid hormones. After induction by desoxycorticosterone, > 90% pure protein was obtained after a single round of metal affinity chromatography. Gentle lysis conditions allowed the preservation of enzymatic activity. Average yields of 10 mg protein per liter of culture were obtained at a fraction of the cost of other eukaryotic expression systems.