We would be nowhere without yeast
Humanity has been using yeast for thousands of years and every day, all over the world, yeast is used to make products such as bread, beer and wine. Yeast is part of our daily diet.
Yeast’s importance has led to it being one of the most well studied organisms in the world, which in turn has allowed yeast to become important in the production of certain pharmaceuticals, vaccines and many other important products.
This versatility and adaptability of yeast is one of its most important and amazing properties. It is “the little engine that could”.
What is yeast?
There are several thousand different yeast species in nature. The main species used to make food and drink (f.x. “Brewer’s yeast”, “Distiller’s yeast” and “Baker’s yeast”) all belong to the genus Saccharomyces, which denotes that these yeasts really like to eat sugar. These yeasts then convert the sugar into a variety of desirable molecules – alcohol and flavors in beer or wine production, carbon dioxide in baking (leavening the dough).
All yeasts are fungi. And all yeasts are eukaryotes. They are much more closely related to plants or animals (also eukaryotes) than are bacteria (which are prokaryotes). Indeed, yeasts are actually quite advanced and complicated organisms (again much more so than bacteria). These two reasons explain why yeasts are so good at making the many complex flavor, color or nutritional molecules that occur in plants and (to a lesser extent) animals.
Saccharomyces cerevisiae: a trustworthy workhorse
The yeast used in baking and beer brewing is Saccharomyces cerevisiae (S.c), This is also the yeast Evolva uses in its production.
S.c was the first “higher organism” ever to be genetically sequenced, back in 1996. This early understanding of the inner nature of S.c spurred a lot of both basic and applied research. Tools for changing how S.c behaves and which molecules it produces followed, and it has become one of the top choices for making a wide number of pharmaceutical and industrial products, in addition to its traditional uses.
S.c has more than 6,000 different genes and today something is known about the function of almost all of them.
Yeast in our service
Saccharomyces cerevisiae was always the production organism of choice for Evolva. Humanity has lived happily alongside it for millennia, and the fact that it is so well studied means it is both easy to adapt for a given use, and lends itself to efficient production by fermentation.
The way yeast make our ingredients is the same as how yeast makes more traditional products.
- For example yeast makes alcohol as the result of the result sequential activity of 10 individual yeast enzymes (which are in turn coded for by 10 individual genes). The yeast turns glucose into alcohol through 9 intermediate molecules
- If we want to yeast to make resveratrol, then the first 14 enzymes (to turn glucose into an amino acid) are already in the yeast. We add in another 4 plant genes to convert the amino acid to resveratrol. Of course there are also other changes to be made to make the whole process as efficient (and economic) as possible. For example we might also upgrade some of the existing genes, take away unwanted genes (f.x. ones that turn resveratrol into something else) and adapt the yeast so it enjoys having high levels of resveratrol around.