Scientists in the US have engineered a new type of yeast that they think could not only improve the quality of wine, but also reduce the properties that give us a hangover if we overindulge.
The team, from the University of Illinois College of Agricultural, Consumer, and Environmental Services (ACES), discovered a genome slicing technique that allows them to easily remove any unwanted copies of a gene in an organism’s DNA. This means, by using an enzyme called RNA-guided Cas9 nuclease as their 'genome knife', the researchers have figured out how to very precisely engineer the genome of the yeast Saccharomyces cerevisiae, which is used widely in the production of wine, beer, bread, and other fermented goods.
"Fermented foods – such as beer, wine, and bread – are made with polyploid strains of yeast, which means they contain multiple copies of genes in the genome," one of the team and associate professor of microbial genomics, Yong-Su Jin, said in a press release. "Until now, it’s been very difficult to do genetic engineering in polyploid strains because if you altered a gene in one copy of the genome, an unaltered copy would correct the one that had been changed."
Being able to tweak wine production, for example, at a genetic level, could be huge. Jin says that using their engineered yeast they could increase the amount of resveratrol in wine by 10 times or more. This natural substance, found in the skins of grapes, blueberries, raspberries, and mulberries, which may or may not impart a plethora of health benefits.
"But we could also add metabolic pathways to introduce bioactive compounds from other foods, such as ginseng, into the wine yeast," says Jin. "Or we could put resveratrol-producing pathways into yeast strains used for beer, kefir, cheese, kimchee, or pickles – any food that uses yeast fermentation in its production.”
Another option would be to clone the enzyme that plays a key role in the process of malolactic fermentation. Improving this process would not only make a smoother wine, the team says, but would slow down the production of the toxic byproducts that are responsible for those dreaded hangover symptoms.
Of course, people will probably have a problem with genetically engineered yeast producing their wine from now on, but Jin says one of the major changes they made to the process was cutting out the need for antibiotic markers.
These markers are often used by scientists when they’re genetically engineering something because they help to point out the regions that have been altered, but this has caused concern over fast-tracking antibiotic resistance. But Jin and his colleagues’ technique works perfectly without them, he says, which means it could have applications across all kinds of genetic engineering research, not just involving yeast and fermentation. "With the genome knife, we can cut the genome very precisely and efficiently so we don’t have to use antibiotic markers to confirm a genetic event."
The team describes the technique in the journal Applied and Environmental Microbiology.
As a 30-year-old who can't have three glasses of wine over dinner without waking up the next morning and feeling like I haven't slept in days, I'm hoping those little yeast organisms can live up to their hangover-demolishing potential. We're counting on you, little buddies.