Making Ethanol from Garbage: Genetically Modifying Yeast
Format
SOECS Senior Project Demonstration
Faculty Mentor Name
George Carman
Abstract/Artist Statement
Yeast has been used by humans for thousands of years to produce ethanol during fermentations. The same holds true today- we still love our beer- only now we have begun using the products of fermentation for fueling our cars as well. Com ethanol has been in the news recently, and there is controversy surrounding the sudden diversion of our com supply, and the effect this has had on parts of our economy. Alternative methods are being pursued to use agricultural waste for ethanol production. lnstead of using the com itself, we could use the parts of the plant that we would otherwise throw away. The problem: it is impossible for yeast to consume cellulose, the structural part of the plant that would provide the bulk of the ethanol. One solution to this has been to introduce enzymes that break down cellulose into glucose,.the yeast's normal food source. Unfortunately, enzymes are costly, making the large-scale production of ethanol prohibitively expensive. We are taking this idea one step further: we propose to create a genetically-modified yeast that can make enzymes to break down cellulose into ethanol. Such yeast will make their own enzymes, in the required amounts, and at the appropriate times, thus eliminating the need to purchase costly enzymes. While the project has yet to be completed, we have accomplished several things so far: we came up with a two-enzyme system that will efficiently metabolize cellulose into glucose; we found an organism that naturally uses this system, and is therefore a good source of genetic material; we have successfully isolated one of the necessary genes and are in the process of inserting it into yeast. When completed, we will evaluate our transgenic yeast for feasibility as a basis for commercial.com ethanol production.
Location
School of Engineering & Computer Science
Start Date
3-5-2008 2:00 PM
End Date
3-5-2008 3:30 PM
Making Ethanol from Garbage: Genetically Modifying Yeast
School of Engineering & Computer Science
Yeast has been used by humans for thousands of years to produce ethanol during fermentations. The same holds true today- we still love our beer- only now we have begun using the products of fermentation for fueling our cars as well. Com ethanol has been in the news recently, and there is controversy surrounding the sudden diversion of our com supply, and the effect this has had on parts of our economy. Alternative methods are being pursued to use agricultural waste for ethanol production. lnstead of using the com itself, we could use the parts of the plant that we would otherwise throw away. The problem: it is impossible for yeast to consume cellulose, the structural part of the plant that would provide the bulk of the ethanol. One solution to this has been to introduce enzymes that break down cellulose into glucose,.the yeast's normal food source. Unfortunately, enzymes are costly, making the large-scale production of ethanol prohibitively expensive. We are taking this idea one step further: we propose to create a genetically-modified yeast that can make enzymes to break down cellulose into ethanol. Such yeast will make their own enzymes, in the required amounts, and at the appropriate times, thus eliminating the need to purchase costly enzymes. While the project has yet to be completed, we have accomplished several things so far: we came up with a two-enzyme system that will efficiently metabolize cellulose into glucose; we found an organism that naturally uses this system, and is therefore a good source of genetic material; we have successfully isolated one of the necessary genes and are in the process of inserting it into yeast. When completed, we will evaluate our transgenic yeast for feasibility as a basis for commercial.com ethanol production.