Technology overview

Advanced cellulase development program fuels ethanol’s success

Cellulosic fuel produced from agricultural waste products, such as corn fiber and  switch grass, represents one of the world’s best hopes for creating sustainable, nonpetroleum-based fuel. However, extracting fermentable sugars from biomass to produce ethanol at low cost is complicated and costly.

The US government has long recognized the critical need for more efficient and more economical enzyme processes to enable cost-efficient mass production of ethanol.

NREL selects Genencor to develop a biotech solution

The US Department of Energy recognized that effective enzyme solutions were most likely to come from the biotech industry rather than the public sector. As a result, the National Renewable Energy Laboratory (NREL) contracted with Genencor in 2000 to develop cellulase enzymes aimed at reducing fermentable sugar costs to less than 20 cents per gallon of ethanol produced.

Overcoming technical hurdles

To meet this goal, we overcame challenges that had been stalling fuel ethanol production for decades, including technical hurdles in protein engineering, novel catalyst identification, and protein strain assembly.

Improved production strains

By integrating a variety of our core technological competencies, we improved our production strain through:

• Better organism selection
• Improved regulation of expression 
• Efficient induction 
• Effective de-repression
• Novel genomics

Improved production processes

Along with enhancing the production strain itself, we focused on improving our host strain engineering and fermentation process techniques.

We achieved:

• Major breakthroughs in production economics 
• Significant economies of scale in product recovery manufacturing

Improved enzyme performance

In addition, improved enzyme performance was critical to achieving NREL's cost-reduction goals. So, we also focused on developing novel cellulolytic activities, discovering new enzymes, and generating protein strain diversity. Genencor’s success resulted from our proven protein engineering capabilities and highly accurate assays and screens.

Goal-breaking cost-reduction results

The Genencor-NREL partnership greatly exceeded expectations by:

• Improving production economics (reduced cost per gram of enzyme)
• Improving cellulase performance (reduced grams of enzyme needed per gallon of ethanol produced)
• Achieving a 30-fold decrease in cellulase costs (far exceeding the original objective of a 10-fold reduction)
• Earning the Top 100 innovations award from R&D magazine

We continue to expand and strengthen our technical capabilities and partnerships in cellulase enzyme development and production to help lower fuel costs - and find sustainable fuel sources - for us all.