Investigating the Role of FLO1 in the Lack of Flocculation of Yeast Brewing Strain Thirsty Pagan Local

Abstract

Brewer's yeast use a fermentation pathway to convert sugars into ethanol in the beer making process. An interesting characteristic most yeast have is the ability to clump together, known as flocculation. Flocculation is useful for brewing companies because it makes it much simpler to separate and reuse it for later brews. Our research is focused on a locally found strain of Saccharomyces cerevisiae, Thirsty Pagan Local (TPL), that does not flocculate, and we want to know why. There are a series of genes associated with flocculation, and FLO1 codes for a protein on the surface of the cell that aids in flocculation. An ethanol sensitivity assay was conducted, and based on this know that FLO1 for TPL is not a null mutant, so it's possible that this gene is simply under expressed. When comparing TPL FLO1 with wild type DL1 FLO1 (a known nonflocculator), we noticed that our FLO1 is roughly 1,000 base pairs shorter than wild type. We are in the process of sequencing TPL FLO1 to find areas where there is a detrimental amino acid change that could give us a clue as to why our strain doesn't flocculate. We have successfully inserted FLO1 into an overexpression plasmid, and plan on conducting a flocculation assay with this plasmid along with FLO1 from a known flocculator, 1195. If the overexpression of TPL FLO1 results in flocculation, our next plan is to establish the overexpression vector permanently into the yeast genome.Support or Funding InformationThe College of St. ScholasticaThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.