In H.G. Wells’s The War of the Worlds, tiny organisms found in nature save the world from powerful high tech invaders that have overwhelmed mankind’s powerful high tech weapons, and in a classic case of life imitating art, there they go again. Microorganisms are playing a big role in the development of sustainable biofuels that could help the U.S. and other developed countries kick the destructive fossil fuel habit. The latest example is a new discovery from a University of Wisconsin research team that could lead to a low cost, high yield process for extracting energy from cellulosic biomass, using a specially developed strain of bacteria.
Cellulosic biomass includes woody nonfood crops like trees, brush, and certain grasses. Until now the difficulty has been finding an efficient way to break down the plant cell wall in woody plants in order to extract the sugar molecules needed to produce biofuel. One approach is to develop new bacteria to do the job and the new research involves one likely candidate, Cellvibrio japonicus, a type of bacteria found in soil.
Bacteria and fungi are natural sugar extractors, but not on a commercially viable scale. Working at the Department of Energy’s Great Lakes Bioenergy Research Center, the researchers have set out to develop a new strain of bacteria that can function far more efficiently. In order to do that they needed to develop a way to analyze the genetic makeup of Cellvibrio japonicus. Until now bacteria have resisted genetic study, but the team achieved a breakthrough by using vector integration, a process that involves the transfer of foreign genetic materials into cells. This procedure enabled the team to induce mutations within any gene in Cellvibrio japonicus. By using the process to disable part of the bacteria’s protein complex, they pinpointed the disctinct enzyme system that the bacteria uses to convert biomass to sugar. The next step is to identify the factors that regulate the system, and determine whether those factors can be manipulated to achieve greater efficiency.
Cellulosic Biomass and a Sustainable Future
With food crops such as corn and soy rapidly falling out of favor, poplar trees and other non-food sources of biofuel are in development. Sustainable cellulosic biofuel crops can be grown on marginal lands, including brownfields, with less water, pesticide and herbicide than food crops require. In the case of trees grown for biofuel, the cropland has the potential to be managed as wildlife and recreation areas, since it is not necessary to cut down the entire tree in order to produce a regular harvest. Still, a rational, national policy on growing cellulosic biomass for biofuels will be needed to forestall competition for arable land with food crops, as demand for biomass is already growing due to the increased use of biomass in electric power plants, including coal-to-biomass conversions in existing power plants.
Imate: Poplar trees by Joost J. Baaker Llmuiden on flickr.com.