Use of an ethanol sensor for feedback control of growth and expression of TBV25H in Saccharomyces cerevisiae

A process for production of a malaria transmission blocking vaccine candidate under the control of the ADH2 promoter in Saccharomyces cerevisiae was developed. Monitoring and controlling the ethanol concentration during the process is essential for successful expression of the recombinant protein. A simple sensor accomplishing this task has been developed, the principle of its operation is the following: air-flow through silicone tubing submerged in the media picks up ethanol, which is detected by an alcohol sensor that relays a signal to a controller regulating the amount of ethanol added to the culture. The sensor was used successfully in high cell density cultures of various scales.