Yeast and the Environment

I had to research a topic in microbiology last semester that involved a microorganism and the environment. My topic was about a yeast strain called Saccharomyces. Several years ago Purdue University genetically modified a strain that could convert both glucose and xylose into ethanol which can be used as a fuel source. Naturally occurring yeast can only ferment glucose but not xylose, a major component of the agricultural residues. Agricultural residues such as straws and hays are mainly composed of cellose and hemicellulose which are usually discarded or used as animal feeds. The genetically modified yeast strain yields 40% more ethanol than the naturally occurring strain. This is very beneficial because not only could we recover more ethanol but we could potentially reduce the amount of waste and reduce the cost of separating the glucose from other sugars.
I’ve heard on the news in the past about cars that used a mixture of ethanol and gasoline to fuel their engines. If the modified yeasts could produce enough ethanol for us to cut down our need for gasoline that would be really wonderful.