Earlier this week we discussed the new breakthroughs with scientists able to make programmable cells that can potentially create new life forms. Now we're reading about yeast that can be controlled with a computer and flashes of light.
The BBC reports that Prof Lygeros joined Prof Mustafa Khammash of the ETH's Biosystems Science and Engineering department and Prof Hana El-Samada's group at the University of California San Francisco have developed a "feedback loop" between a computer and a type of yeast commonly used in brewing and baking, which can be used to control which genes are switched on or off. The research appears in the journal Nature.
In order to turn genes on or off, the computer uses flashes of light at different levels of red -- a lighter red makes it active and a deeper red switches it back. As BBC reports:
The activity of the phytochrome can start or stop the genetic machinery that results in the production of a given protein. The team used this trick to ensure that when the yeast was producing that protein - corresponding to the gene being switched on - it could be tracked by using a "reporter" molecule that itself gives off light in a process called fluorescence. In that way, the team had a full loop of control: upon shining red light in, they could track how much a population of yeast cells was expressing the gene, and apply the deeper red to curb that gene expression.
The scientists hope that this type of research can potentially control or improve biological processes like the production of biofuel from microbes. Prof Lygeros explained to BBC, "It's quite difficult to engineer synthetic circuits that do something robustly in the cell, and the hope is that by augmenting this with external signals, you can get them to behave better. That for example may have applications in biofuel production, or antibiotic production, where they use genetically engineered organisms to increase the yields of reactions."