Mascoma Achieves Set of Research Advances with Cellulosic Biofuels; Proof of Concept for Consolidated Bioprocessing
Mascoma Corporation has made major research advances in consolidated bioprocessing, or CBP, a low-cost processing strategy for production of biofuels from cellulosic biomass. (Earlier post.) Presented by Mascoma Chief Technology Officer Dr. Mike Ladisch at the 31st Symposium on Biotechnology for Fuels and Chemicals in San Francisco, the advances, which provide proof of concept for CBP, include developments with both thermophilic bacteria to produce ethanol and recombinant cellulolytic yeasts to break down the cellulose.
CBP avoids the need for the costly production of cellulase enzymes by using engineered microorganisms that produce cellulases and ethanol at high yield in a single step. Pre-treatment opens up the structure of the biomass by disrupting the lignin seal and exposing cellulosic plant cell wall components. This gives the CBP microorganisms—which generate the enzymes to hydrolyze cellulose into fermentable sugars and also ferment the sugars to ethanol—access to the cellulosic constituents.
This one-step conversion process lowers costs by limiting additives and enzymes used in other biochemical processes.
Mascoma is combining naturally occurring metabolic activities in single microorganisms by modifying the fermentative pathways of the most efficient processors of cellulose, including the thermophilic anaerobic bacterium Clostridium thermocellum, to produce high yields of ethanol from hardwoods and other biomass. Mascoma had earlier demonstrated the ability to modify the fermentative pathways of a thermophilic anaerobe for high ethanol yield from sugars through the metabolic engineering of Thermoanaerobacterium saccharolyticum.
This is a true breakthrough that takes us much, much closer to billions of gallons of low cost cellulosic biofuels. Many had thought that CBP was years or even decades away, but the future just arrived. Mascoma has permanently changed the biofuels landscape from here on.—Dr. Bruce Dale, MSU and Editor of the journal Biofuels, Bioproducts and Biorefineries
Among Mascoma’s reported advances are:
Production of nearly 6% wt/vol ethanol by an engineered thermophilic bacterium, an increase of 60% over what was reported just a year ago;
The first report of targeted metabolic engineering of a cellulose-fermenting thermophile, Clostridium thermocellum, leading to a reduced production of unwanted organic acid byproducts; and
Selected strains of C. thermocellum that can rapidly consume cellulose with high conversion and no added cellulase, and grow on cellulose in the presence of commercial levels of ethanol.
A 3,000-fold increase in cellulase expression from recombinant, cellulolytic yeast;
A significant 2.5-fold reduction in the added cellulase required for conversion of pretreated hardwood to ethanol; and
Complete elimination of added cellulase for conversion of waste paper sludge to ethanol.
These advances enable the reduction in operating and capital costs required for cost-effective commercial production of ethanol, bringing Mascoma substantially closer to commercialization. Our results go a long way toward establishing the feasibility of the processing concept that we have built our company around—so this is a big day for us.—Jim Flatt, Executive Vice President of Research, Development and Operations at Mascoma
Separately at the Symposium, Dr. Ladisch was presented with the Charles D. Scott Award. The award is administered by the Society for Industrial Microbiology and recognizes contributions to the biotechnology fuels and chemicals field as a whole, particularly innovation in fundamental and applied biotechnology, insight into bioprocessing fundamentals, or commitment to facilitate commercialization of products from renewable resources.
Dr. Ladisch is the third Mascoma executive to win the award; company cofounders Drs. Charles Wyman and Lee Lynd were recipients in 1999 and 2005, respectively.
In addition to his role at Mascoma, Dr. Ladisch is Director of the Laboratory of Renewable Resources Engineering and Distinguished Professor of Agricultural and Biological Engineering with a joint appointment in Biomedical Engineering at Purdue University and courtesy appointment in Food Science.
In February 2009, Mascoma announced that its pilot facility in Rome, NY had begun producing cellulosic ethanol. The demonstration facility, which was constructed with support from the State of New York through the NYS Department of Agriculture & Markets and the New York State Energy Research and Development Authority, has the flexibility to run on numerous biomass feedstocks including wood chips, tall grasses, corn stover (residual corn stalks) and sugar cane bagasse.
The facility will provide process performance engineering data sufficient to support construction of 1/10th scale and commercial scale biorefineries in Kinross, MI, with support from the Department of Energy and State of Michigan.
In 2008, General Motors Corp. and Mascoma Corp. entered a strategic relationship to develop cellulosic ethanol based on Mascoma’s Consolidated Bioprocessing. The relationship includes an undisclosed equity investment by GM.
(Proceedings from the 31st Symposium on Biotechnology for Fuels and Chemicals will be published later available for purchase.)
31 SBFC Oral Presentation 7-03: Development and Deployment of Consolidated Bioprocessing for the Poduction of Ethanol, M. Ladisch et al.