The key to making bread is yeast and the quality of the yeast can vary as a result of genetic inconsistency. Using the baker’s yeast Saccharomyces cerevisiae, researchers have developed a new method to overcome the effect of genetic mutations.
Using new methods, a science team have gained a better understanding of what affects the quality of baker’s yeast. Baker’s yeast refers to the yeast commonly used as a leavening agent in baking bread. The yeast converts the fermentable sugars present in the dough into carbon dioxide and ethanol.
Baker’s yeast is similar to brewer’s yeast (used to make ales and lager.) Brewer’s yeast and baker’s yeast both work in a similar way, in that they turn sugars into alcohol and carbon dioxide. Moreover, both of these yeasts are made from strains of the Saccharomyces cerevisiae fungus. However, different strains of this yeast species are used for the different processes. Brewer’s yeast and baker’s yeast differ in their composition, uses and health factors.
For the research, the scientists focused on a gene called TDH3. This gene helps baker’s yeast cells convert sugar into energy used for growth. The focus of the inquiry was to see how different genetic mutations affected TDH3 expression. To show this, the researchers used genetic methods to change around the DNA base pairs in a region of the gene called the promoter.
Through this method, the scientists produced all of the possible genetic mutations. This allowed the researchers to survey natural yeast strains to determine which strains provided the key genetic “recipes” in order to make the perfect loaf.
The study has been published in the journal Nature. The paper is called “Selection on noise constrains variation in a eukaryotic promoter.”
