Researchers engineer world’s first yeast that harnesses energy from light

Yeast is sunlight shy. It's generally recommended to store yeast in a cool, dry place such as the refrigerator to maintain its quality, given that it’s a living organism, and excessive heat or direct sunlight can negatively impact its viability. In hotter climates, think Sicily in July, the shelf life of can be significantly reduced.

So, researchers from Georgia Tech’s School of Biological Sciences have crafted yeast strains that seem to thrive when nature's spotlight is on. “We were frankly shocked by how simple it was to turn the yeast into phototrophs (organisms that can harness and use energy from light),” said Anthony Burnetti, a research scientist working in Associate Professor William Ratcliff’s laboratory and corresponding author of the study.

“All we needed to do was move a single gene, and they grew 2% faster in the light than in the dark. Without any fine tuning or careful coaxing, it just worked,” added Burnetti. Since is a crucial commodity, this could be a game changer in figuring out things like making biofuels, how living things change over time, and how cells age.

Guess we can now make pizza dough in blaring heat. Interestingly, the researchers at Georgia Tech were inspired by their previous work on the evolution of multicellular life and wanted to explore using light as an energy source for organisms. They looked at , proteins that can turn light into energy.

Then, they added a rhodopsin gene from a parasitic fungus into regular baker's yeast using horizontal gene transfer. “Rhodopsins are found all over the tree of life and apparently are acquired by organisms obtaining genes from each other over evolutionary time,” said Autumn Peterson, a biology Ph.D.

student and lead author of the study. Horizontal gene transfer involves sharing genetic information between organisms that aren’t closely related. This genetic shuffle can lead to rapid and surprising evolutionary leaps. “In the process of figuring out a way to get rhodopsins into multi celled yeast,” explains Burnetti, “we found we could learn about horizontal transfer of rhodopsins that has occurred across evolution in the past by transferring it into regular, single celled yeast where it has never been before.” After putting the rhodopsin gene into ordinary baker's yeast, the modified yeast exhibited a 2% growth increase when exposed to light.

The simplicity of this genetic modification raises possibilities for studying cellular aging and improving bioproduction, with potential applications in synthesizing . “Here we have a single gene, and we're just yanking it across contexts into a lineage that's never been a phototroph before, and it just works,” said Burnetti.

“This says that it really is that easy for this kind of a system, at least sometimes, to do its job in a new organism.” Their study was published in the journal ..