Making Yeast More Tolerant at Higher Temperatures - Admission/Application Essay Example

The world is fast running out of fossil fuels, in particular, crude oil. There is a great need to find alternative fuels that are preferably non-polluting, renewable, and do not cause global warming. One viable alternative is a biofuel which is fuel derived from plants or crops. It involves a chemical process by which the sugars contained in plants are converted to ethanol. The primary agent in this process is yeast to cause fermentation or the way by which a plant's sugars (mainly glucose) in the cellulose or starch are converted by the anaerobic process into ethanol (a form of alcohol) by the action of yeast enzymes. However, yeast enzymes are often susceptible and very sensitive to ethanol toxicity that limits industrial production.

The research study done by Caspeta et al. was intended to solve this problem by use and selecting specific yeast strains through laboratory evolution that are tolerant at the ≥40°C temperature at which ethanol production is maximized through both saccharification and fermentation processes. The research study authors experimented by sequencing the whole genome, studying genome-wide expressions, and analyzing the metabolic-flux by which they discovered a change in sterol composition, from ergosterol to that of fecosterol.