02/14/2011

Learning New Tricks from Fungi to Improve Biomass Processing

Summary

Knowing how biomass is degraded in nature will advance understanding in how to process biomass for conversion to biofuels. The biodegradation of plant material generally involves removal of the resistant lignin barrier that prevents enzymes from reaching cellulose and degrading it to sugar. However, brown rot fungi, natural biomass recycler in coniferous forests, degrade biomass without removing much of the lignin. DOE researchers at the University of Wisconsin, Madison, and the Great Lakes Bioenergy Research Center (GLBRC) in Madison, Wisconsin, report that these fungi can disrupt the lignin in wood even though it remains in place. They discovered that key chemical linkages (ethers) in lignin’s complex molecular structure are broken, likely using reactive oxygen species such as hydroxyl radicals. They applied newly developed nuclear magnetic resonance (NMR) technology to look at the chemistry of wood attacked by a brown rot fungus. These results will enable development of new routes to access cellulose in biomass as part of the large-scale production of biofuels and will also improve understanding of natural carbon cycling from wood.

References

Yelle, D., D. Wei, J. Ralph, and K. E. Hammel. 2011. “Multidimensional NMR Analysis Reveals Truncated Lignin Structures in Wood Decayed by the Brown Rot Basidiomycete Postia placenta,” Environmental Microbiology doi:10.1111/j.1462-2920.2010.02417.x.