Grantee Research Project Results
Final Report: Recombinant Lignin-Degrading Enzymes to Digest Wood for Biofuel Production
EPA Grant Number: SU835083Title: Recombinant Lignin-Degrading Enzymes to Digest Wood for Biofuel Production
Investigators: Williams, Myron N.V. , Murray, Dejean , Rice, Demicca , Oatis, Etienette , Kiros, Filmon , Melnyczuk, John , Hines, Tara , Ross, Wendie
Institution: Clark Atlanta University
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2011 through August 14, 2012
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2011) RFA Text | Recipients Lists
Research Category: P3 Challenge Area - Air Quality , P3 Challenge Area - Chemical Safety , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities
Objective:
The objective of our research is to enhance the yield of biofuels, particularly cellulosic ethanol, that can be generated from forest, agricultural and urban wastes. The Southeast of the United States should take advantage of biomass alternative energy sources, and woody biomass is already economically important in Georgia. A problem associated with harvesting cellulosic energy from woody wastes is that the cellulose is tightly bound with lignin in plant secondary cell walls, a complex known as lignocellulose. Enzymatic degradation of lignin could increase yields of cellulosic products, and can be performed under mild condition, thus reducing expenses and environmental costs. The project goals will be achieved by producing lignin peroxidase in vitro and using it to treat woody wastes, containing lignocelluloses prior to or concurrently with digestion by cellulase. This treatment, which does not require harsh & polluting conditions, should increase in the yield of fermentable glucose (and correspondingly ethanol) by as much as 30%. Ambient lignin-degradation will be made economically feasible by overproduction of the enzyme in a recombinant E coli system, and modification of the gene for better enzyme activity.
Summary/Accomplishments (Outputs/Outcomes):
The gene for a lignin-degrading enzyme, lignin peroxidase, has been designed and chemically synthesized based on a fungal source (Phenerochaete chrysosporium). The gene has been placed in an expression vector for high level, inducible expression and secretion from E. coli. Induction of E. coli carrying the vector results in secretion of soluble proteins into the culture medium, which exhibit lignin peroxidase activity without the need for elaborate lysis and refolding procedures. Alternative industrial uses for the recombinant lignin peroxidase are being investigated. A group of students, primarily from groups underrepresented in the STEM fields, have received training in experimental approaches and design, as well as in biochemical methods.
Conclusions:
The Phase I project has achieved 80% of its milestones to date and, based on these successes, new goals for Phase II have been articulated. A sustainable format for creating interdisciplinary research groups has been created, and a continuing project initiated. Expansion of the project to include additional disciplines and institutions is planned
Journal Articles:
No journal articles submitted with this report: View all 2 publications for this projectSupplemental Keywords:
lignin degradation, recombinant enzymes, peroxidases, hemeproteins, commercialization, E. coli, bioethanol, saccharificationThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.