CBI: Center for Bioenergy Innovation

The Center for Bioenergy Innovation (CBI), led by Oak Ridge National Laboratory (ORNL), is pursuing a variety of new technologies to cost effectively create fuels and products currently made from petroleum. Through basic science research on dedicated bioenergy crops (e.g., poplar and switchgrass) and a suite of engineered microbes, CBI researchers are advancing the domestication and design of plants and microbes to produce advanced biofuels and bioproducts, including hydrocarbons for jet fuel and chemical feedstocks for plastic precursors.

Specifically, the CBI team is accelerating progress toward identifying and using key plant genes for growth, yield, composition, and sustainability traits to lower feedstock costs and improve year-round feedstock supplies. Additionally, CBI is developing consolidated bioprocessing (CBP), a process in which microbes simultaneously digest the biomass and convert it to biofuels and bioproducts without added enzymes. CBP combines multiple approaches and tools to overcome industrially relevant barriers to using microbes in biomass deconstruction and conversion, including brief milling during deconstruction (i.e., cotreatment).

Finally, CBI is committed to translating its research results into applications and potential commercial deployment to meet DOE’s bioenergy objectives. Through economic and sustainability analyses, CBI is assessing how its research on new supply chains and process configurations will reduce cost and scale-up risk across the bioenergy supply chain, from biomass planting and harvest all the way through conversion to fuels and products.

Ultimately, CBI aims to:

• Create high-yielding bioenergy crops, which display uniform productivity and increased sustainability, by harnessing natural diversity via genomic selection in two perennial feedstocks, poplar and switchgrass.
• Engineer CBP microbes to produce commercially relevant quantities of advanced biofuels.
• More completely utilize all plant cell wall components, specifically lignin, to funnel and improve biological production of coproduct chemicals and novel materials.

Research Focus Areas

CBI’s research targets three research focus areas: (1) improving sustainable biomass feedstocks, (2) enhancing biomass deconstruction and conversion through CBP into specialty fuels, and (3) transforming lignin residues into valuable bioproducts. An underlying theme is to accelerate the domestication of bioenergy-relevant plants and microbes to enable innovations across the bioenergy supply chain by understanding and manipulating complex traits controlled by multiple genes.

Sustainable Biomass Feedstocks. In the last two years, CBI has identified, characterized, and utilized key plant genes for yield, cell wall composition, and sustainability traits as a means of achieving lower feedstock costs. Focusing on native perennial plants, such as poplar and switchgrass, provides immediate advantages in sustainability, including fewer chemical inputs and better soil conservation. CBI researchers are harnessing the vast natural diversity in these two dedicated bioenergy crops to uncover the genetic determinants of complex traits related to cell wall chemistry, disease resistance, favorable mycorrhizal colonization, and drought tolerance via genomewide association studies (GWAS), genomic selection, and genomic editing approaches to design uniform high-yielding, high-quality, resource-efficient feedstocks. CBI’s overarching sustainability goals are to discover and develop poplar and switchgrass genotypes with superior water-use efficiency, nitrogen-use efficiency, and pathogen resistance. CBI researchers are using these genotypes in genomic selection programs to discover and test key genes and mechanisms underlying these important sustainability traits and to characterize and deploy beneficial plant microbes to increase the yield stability of plants under low-input and environmentally challenging agricultural conditions. Recent advancements in plant phenotyping are being combined with artificial intelligence–based genomic selection approaches and CRISPR gene editing tools to provide innovative systems biology platforms for identifying unique biotechnological traits and developing improved, sustainable nonfood bioenergy crops.

Consolidated Bioprocessing. CBP eliminates the need for added enzymes and pretreatment, which are the two largest processing cost components in fuel production. CBI scientists are focused on robust microbial platforms for converting targeted feedstocks to jet fuel and other specialty fuels and developing consolidated, one-step saccharification and fermentation processes at high rates, titers, and yields. CBI is similarly evaluating CBP combined with a brief milling during fermentation (i.e., cotreatment) for enhanced deconstruction efficacy, lignin valorization potential, and economic viability. CBI technoeconomic analyses estimate that the process intensification associated with combining saccharification and fermentation will reduce both capital and operating costs to scale up the technology. Also being addressed are the fundamental and broadly enabling science questions that arise during the domestication process for new CBP microbes. CRISPR-based gene editing tools for rapid domestication of nonmodel microorganisms are providing the foundational science for a promising and relatively unexplored branch of biotechnology that is applicable to a wide range of host organisms and relevant to the new bioeconomy. CBI researchers are extending the CBP work into hybrid processes to catalytically upgrade alcohols and aromatics into liquid biohydrocarbons functionally equivalent to petroleum (i.e., drop-in biofuels). In the past two years, the sugar residues most recalcitrant to CBP solubilization have been identified, and CBI researchers have shown that the solid residues remaining after CBP are enriched in the industrially exploitable aromatic lignin polymer. In addition, using super high-resolution microscopy, CBI researchers recently uncovered the unique interfacial environment where cellulolytic microbes interact with the biomass surface.

Valuable Lignin Bioproducts. As an example of accelerated domestication and convergent design of plants and microbes, CBI is developing methods to transform lignin-rich residues remaining after CBP into valuable bioproducts, including chemical feedstocks such as propanol guaiacol and propanol catechol. First, CBI researchers are modifying lignin in planta to maximize the number of carbon-oxygen bonds via genetic diversity and engineering, enabling the production of lignin designed for deconstruction. Second, reductive catalytic fractionation (RCF) is being used to further optimize the deconstruction process. This technique solubilizes and partially depolymerizes the lignin by targeting the carbon-oxygen bonds, utilizing natural diversity and modifications of plant cell walls. RCF is also proving to be a useful analytical tool for characterizing and examining lignin composition and degradation.

Finally, CBI researchers are employing biological funneling to produce the chemical precursors for plastics. In this process, microbial biocatalysts are designed to (1) exhibit ligninolytic aromatic-catabolic activities, (2) funnel heterogeneous aromatic monomers to central aromatic intermediates, and (3) produce target chemical feedstocks from lignin via atom-efficient transformations. CBI targets three lignin-derived products (cis,cis-muconic acid; 2-pyrone-4,6-dicarboxylic acid; and α-ketoadipate) that can be cost effectively converted into precursors for commodity polymers such as adipic and terephthalic acids.

Industry Interactions

CBI seeks to form important industrial relationships, disseminate CBI research results, gain feedback on industrial bottlenecks and concerns, and generate information about commercial opportunities including collaborations. Significant interactions have occurred with various companies including DSM; Forage Genetics International; Gevo; Commercial Aviation Alternative Fuels Initiative (CAAFI); White Dog Labs, Inc.; and Phenotype Screening Corporation. In addition, CBI, DOE’s Joint Genome Institute, and LanzaTech are completing a collaboration to release the genome sequences of 200 to 300 industrial clostridial species.

CBI intellectual property (IP) is disclosed to CBI’s Commercialization Council, which consists of technology transfer representatives from each CBI partner institution. The council reviews new CBI-funded inventions by considering their technical merit and commercial potential in order to develop an IP strategy and share licensing leads. Each owner institution protects its CBI inventions according to its standard practices and coordinates any joint IP. In fiscal year 2019, CBI partners submitted 10 invention disclosures, six provisional patent applications, four utility patent applications, and five issued patents.

Education and Outreach

CBI offers interdisciplinary research opportunities for graduate students, postdoctoral researchers, and visiting scientists and also seeks to broaden public understanding of bioenergy and the pipeline of future bioeconomy workers. Working with the Creative Discovery Museum in Chattanooga, Tennessee, the CBI-supported “Farming for Fuels” hands-on or distance-learning programs have reached more than 290,000 students, parents, and teachers nationwide over 11 years through hubs at multiple science centers or museums across 14 states. These materials incorporate Next Generation Science Standards (K-12 science content standards) and are available at learnbioenergy.org. The lessons were downloaded by ~29,000 users last year. The ongoing program is self sustaining with direct costs only in training, distance learning, and curricula development.

CBI Partners

• Oak Ridge National Laboratory (Oak Ridge, Tennessee; lead institution)
• Colorado State University (Fort Collins)
• Dartmouth College (Hanover, New Hampshire)
• GreenWood Resources, Inc. (Portland, Oregon)
• Massachusetts Institute of Technology (Cambridge)
• National Renewable Energy Laboratory (Golden, Colorado)
• Noble Research Institute (Ardmore, Oklahoma)
• The Pennsylvania State University (State College)
• University of California (Riverside)
• University of Colorado (Boulder)
• University of Georgia (Athens)
• University of North Texas (Denton)
• University of Tennessee (Knoxville)
• University of Wisconsin (Madison)
• West Virginia University (Morgantown)

CBI Contacts

• https://cbi.ornl.gov/
• Oak Ridge National Laboratory
  Oak Ridge, TN 37830
• Gerald Tuskan, tuskanga@ornl.gov