06/30/2011
In Search of Enzymes for Biofuel Production
The Science
Some microbes contain enzymes that can break down lignocellulosic biomass, such as that found in switchgrass or Miscanthus. But there are few suitable methods for finding these enzymes in complex microbial communities. Researchers at the DOE Joint BioEnergy Institute (JBEI) have developed a new method that uses nanostructure initiator mass spectroscopy (NIMS). It enables rapid and accurate characterization of enzymes in complex microbial and environmental samples (e.g., microbial compost). Using this new technology, JBEI researchers have characterized a broad range of environmental and purified microbial samples, further optimizing selected samples for enzymatic activity and stability in the presence of ionic liquids, which are being tested by JBEI for use in biofuel production. This new NIMS-based approach may aid in finding more efficient ways to convert biomass into lignocellulosic biofuels.
The Impact
This assay system can be used directly with crude environmental samples and under extreme reaction conditions (high temperatures, extreme pH values, presence of ionic liquid). Therefore, it presents a novel method for high throughput screening and detection of novel secreted (hemi)cellulolytic activities in microbial communities. Ultimately, this approach may potentially aid in finding a more efficient way to convert biomass into lignocellulosic biofuels.
Summary
There is growing interest in the production of biofuels from lignocellulosic biomass (e.g. switchgrass or Miscanthus) which is a highly abundant renewable resource that can be converted into potentially carbon-neutral transportation fuels. The basis for this approach is the deconstruction of plant cell walls into sugar monomers which can be fermented into ethanol. The efficiency of the breakdown of (hemi)celluloses is closely connected to the availability of optimal (hemi)cellulases. The enzymatic hydrolysis of polysaccharides into fermentable sugars is a crucial step in the conversion of biomass to lignocellulosic biofuels. An efficient hydrolysis is highly dependent on the identification and characterization of optimal glycoside hydrolases. However, existing techniques for characterizing activity are limited by the range of reaction conditions that can be used, sample complexity, and throughput. The method these researchers present is a multiplexed approach based on nanostructure-initiator mass spectrometry (NIMS) that allows for the rapid analysis of several glycolytic activities in parallel under diverse assay conditions.
Principal Investigator
Trent Northen
Joint BioEnergy Institute
BER Program Manager
Ramana Madupu
U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]
References
Reindl, W., K. Deng, J. M. Gladden, G. Cheng, A. Wong, S. W. Singer, S. Singh, J.-C. Lee, C.-H. Yao, T. C. Hazen, A. K. Singh, B. A. Simmons, P. D. Adams, and T. R. Northen. 2011. “Colloid-Based Multiplexed Screening for Plant Biomass-Degrading Glycoside Hydrolase Activities in Microbial Communities,” Energy and Environmental Science 4, 2884–93. DOI:10.1039/C1EE01112J.