Course Meeting Times
Lectures: 1 session / week, 2 hours / session
Students should have a good working knowledge of molecular biology, cell biology, and genetics. Recommended prerequisites are:
7.05 General Biochemistry
7.06 Cell Biology
7.28 Molecular Biology
The need to identify sustainable forms of energy as an alternative to our dependence on depleting worldwide oil reserves is one of the grand challenges of our time. The energy from the sun converted into plant biomass is the most promising renewable resource available to humanity. Almost all of this energy is contained within cellulose, the natural yet difficult to digest polymer of sugars that make up plant cell walls. How can we unlock the energy within cellulose and convert it to more useful forms of energy? Fortunately, nature has evolved several enzymes that work together to break down cellulose. These enzymes are found within bacteria and fungi that thrive in cellulose-rich environments (e.g., the digestive tracts of grazing animals, compost piles, and soil). Sugars released from cellulose hydrolysis can later be fermented into biofuels like ethanol.
We will examine each of the critical steps along the pathway towards the conversion of plant biomass into ethanol. We will focus on the biology behind enzymatic cellulose breakdown, the different types of enzymes required, and how these enzymes form complexes in nature that improve their catalytic performance. State-of-the-art methods currently in use to identify new cellulolytic enzymes with novel properties as well as metabolic engineering strategies to introduce these enzymes into yeast and other organisms will be discussed. We will further examine issues associated with industrial-scale production and catalytic performance of cellulolytic enzymes; such issues have limited the economic feasibility of cellulosic biofuels.
This course aims to equip students with the ability to search, review, and analyze the primary research literature. By the end of the course, students will have a broader knowledge regarding the biology behind cellulose breakdown, the challenges associated with industrial biofuel production, and new opportunities to further its development.
Each class will generally focus on the discussion of two papers from the primary research literature, listed in the course syllabus for each class meeting. Prior to each meeting, students are expected to have read the appropriate papers and may use on-line literature databases for optional background reading. Students should be prepared to discuss the selected papers in class. At the end of each class, the necessary background to understand the papers for the next session will be provided by the instructor in a 10 – 15 minute lecture.
Requirements and Grading
This course is graded pass/fail. Successful conclusion of the course requires the completion of two assignments and regular participation in the weekly meetings.
|WEEK #||TOPICS||KEY DATES|
|1||Welcome and Introductions|
|2||Cellulose Breakdown Basics|
|3||Cellulolytic Bacteria and Fungi|
|7||Guest speaker: Industrial Biomass Processing and Hydrolysis||Written assignment due|
|9||Engineering Cellulolytic Organisms|
|10||Directed Evolution and Protein Engineering||Deadline to select a paper for oral presentation|
|11||Identifying New Cellulases from Nature|