Gasoline as a primary source of energy is a doomed enterprise and one whose doom always seems to be rapidly approaching. We have all heard it and we all know it by now. So the question is how do we overcome that? Well there are a number of competing answers to that question, but one of the most promising is that of engineering our own biofuels. A 2012 review from UC Davis published in the Journal of Biotechnology examines a range of experimental results from the field of bioengineering and highlights one of the more exciting new prospects in the search for sustainable fuels: cyanobacteria.
Cyanobacteria, or blue-green bacteria (or even blue-green algae if you prefer), is a phylum of bacteria that uses photosynthesis to derive its energy and produce oxygen by fixing CO2. Researchers have begun developing ways to hijack varying cyanobacteria species’ metabolic machinery to produce new chemicals in place of the sugars they usually create to drive ATP synthesis. In particular, they have managed to engineer strains of Synechococcus elongatus and different Synechocystis species to produce what they believe to be economically viable biofuels.
The paper describes four new methods of bioengineering that allowed for the production of synthetic fuels. By inserting genes for new enzymes from other bacterial species, researchers were able to alter the metabolic pathways that run within the cyanobacteria. This allowed them to create whole new branches off the species’ natural metabolic processes that would result in new products, in these cases opting for highly volatile fuel sources such as isobutyraldehyde, isobutanol, and the lipids used to produce biodiesel.
Cyanobacteria present a very exciting possibility in biofuel production. Unlike corn, the primary source of ethanol which is often touted as the primary alternative to gasoline dependence, cyanobacteria can be grown in non-arable areas and require little to no input to grow (pretty much only needing water, light, and CO2 according to the paper). This would allow for these organisms to be grown almost anywhere while also opening doors for the engineering of bioreactors which would house large populations for industrial-scale production.
Arguably the strongest point on the side of cyanobacteria versus fuel sources like ethanol is their significantly lighter impact on the environment. Agriculturally derived biofuels require huge amounts of land which would otherwise be devoted to food production. This is particularly noticeable in the developing world, where these crops are seen as highly profitable for export and are often chosen over crops which would better support the needs of the nation itself. At the same time, maintaining the sheer quantity of arable land necessary to support agricultural biofuel production often requires severe deforestation, which carries its own legion of ramifications in the realms of conservation and ecology.
Overall, biofuel production using engineered strains of cyanobacterai and other microorganisms presents a cost-effective and relatively low-impact alternative to both current fossil fuel sources and other potential alternatives. Oh and did I mention it would be fairly easy to incorporate it into the existing fuel infrastructure? Because according to the review, it even trumps ethanol in its compatibility with how we already distribute fuel. This is definitely a field to keep an eye on as the race for a viable, sustainable alternative to gasoline continues.
Original article: http://www.sciencedirect.com/science/article/pii/S0168165612001721