Yeast engineered for biofuels

Candidate—Jon Galazka, UC Berkeley

Nominated by Jamie Cate, UC Berkeley

The Deloitte QB3 Award for Innovation recognizes a graduate student, postdoc, staff scientist, or team from UC Berkeley, UC Santa Cruz, or UCSF who has made an advance with the capacity to improve human health. Candidates for were nominated by QB3 faculty. Finalists were chosen by a panel of expert judges.

We asked each nominee (or team) to answer a series of short questions, to give a snapshot of their project. Read their answers below. Leave a comment to let us know what you think!

Jon Galazka.

Please describe your innovation.
This innovation consists of a yeast strain that converts the two most abundant sugars in plant cell walls to fuel. Plant cell walls can be converted to liquid fuel without raising food prices. However, this process is limited by yeast’s inability to simultaneously ferment glucose and xylose; yeast sugar transporters vastly prefer glucose. This innovation overcomes this by porting a cellobiose transport pathway into yeast. Cellobiose, a dimer of glucose and the repeating unit of cellulose, enters yeast through the exogenous transporters and is cleaved to glucose. The endogenous transporters are thus free to transport xylose, allowing simultaneous fermentation.

Within the 140-character Twitter limit:

What’s the impact?
Helps expand global energy supplies, which underpin human health and welfare. More energy is needed to lift 1.3 billion people from poverty

What’s the novelty?
Uses a formerly unknown family of transporters, is a new route for glucose to enter yeast, and eliminates a barrier to biofuel production

What’s the utility?
Is undergoing commercial development by BP Biofuels and is a cornerstone in their plans for sustainable cellulosic biofuel production

Complete conversion of plant biomass to fuel involves more than just fermenting glucose to ethanol.

How does your research topic represent a strong advance in human health? And how will it influence the way we operate in science in the future?
Access to clean, reliable, and affordable energy sources is intimately linked to human health and welfare. Increased energy supplies allow individuals to be more mobile and productive, and are required for economic growth. Therefore, expanding global energy production is critical to lifting people in poverty to acceptable living standards. This innovation eliminates a barrier to fuel production from biomass, and will help diversify and expand global energy supplies. Furthermore, this innovation has caused scientists to rethink their assumptions about fuel production from plants, catalyzing new research into all aspects of the process.

References:
Cellodextrin Transport in Yeast for Improved Biofuel Production
Jonathan M. Galazka, Chaoguang Tian, William T. Beeson, Bruno Martinez, N. Louise Glass, and Jamie H. D. Cate
Science, 1 October 2010, Vol 330, no. 6000 pp. 84-86

Engineered Saccharomyces cerevisiae capable of simultaneous cellobiose and xylose fermentation
Suk-Jin Ha, Jonathan M. Galazka, Soo Rin Kima, Jin-Ho Choi, Xiaomin Yang, Jin-Ho Seo,
N. Louise Glass, Jamie H. D. Cate, and Yong-Su Jin
PNAS, January 11, 2011 vol. 108 no. 2 504-509