August 2, 2007 If you ever doubt the creativity of modern science, just throw a serious challenge at it and watch the myriad responses you receive. Rising oil prices and historical data are signifying that Hubbert’s “peak oil” may be upon us, and the rush is on all over the world to find viable alternative energy sources to replace the dwindling crude that’s powered us into the technology age. But what if we could just ‘grow’ more oil? The deadly bacteria E. coli, might seem like an unlikely ally, but scientists in California are claiming they have successfully genetically manipulated the deadly bug and a host of other bacteria to produce pure hydrocarbon chains that can be processed into biofuels. In fact, they’re getting so good at it that they can coax the bacteria into producing a substance that’s exceptionally close to crude oil – minus the sulfur impurities that taint the oil we pump out of the ground - and ready to be put through a standard refinery to produce petrol, diesel, jet fuel or any other petroleum product. There’s also talk of other, far more pure and powerful fuels that need no further refinement before they go to the pump. Could the next great oil barons be bug farmers?
Bacteria are among the most simple of biological organisms, which makes them a great starting point for the emerging technology of bioengineering. LS9, one of the companies working on engineering fuel-producing bacteria, define this new field of synthetic biology as “the design, construction and improvement of biological machines at the molecular genetic level”.
Crude oil, a naturally occurring substance, is widely believed to be the product of compressing and heating decomposed ancient organic materials such as algae and prehistoric zooplankton over time in the earth’s crust. Its molecular structure consists mainly of hydrocarbon chains of different lengths and when burnt, these hydrocarbons release significant amounts of energy.
According to LS9: “The components of petroleum have biological counterparts, and the biological mechanisms for their synthesis are useful tools for the creation of new industrial processes. Employing the tools of biochemical engineering, LS9 has identified the key components of a cost effective process and defined which are best controlled physically, chemically, and biologically. Using synthetic biology, LS9 has reached into nature and accessed the required biological tools, engineered them to function under industrial conditions, and is optimizing their performance to meet our economic objectives.”
Effectively the science focuses on the way bacteria store energy as fatty acids. These fatty acids are very close in structure to fuel hydrocarbons and minute changes to the genetic and biological structures of the bacteria can be made to make them produce and excrete useful compounds.
Competing company Amyris explains their process further: “We focus on creating new metabolic pathways in microbes, essentially re-programming them to function as living factories for the environmentally-friendly production of high-value chemicals.”
While LS9 appears to be focusing on building bacterial factories to directly synthesize crude oil, Amyris are taking the opportunity to explore the engineering potential of developing cheaper, cleaner and more powerful biofuels. This approach seeks to optimize the product rather than replicating the random nature of crude.
Amazing though these advances in biotechnology are, they still require source materials for the bacteria to work on – this includes source materials similar to that used for the production of ethanol fuel like corn, wheat, rice and soybean crops, but there is also potential to utilize cellulosic biomass derived from cheaper and more readily available sources such as perennial grasses like switchgrass, plant wastes and even sawdust. While the former are relatively easy to produce, there’s currently little hope of using them to replace the amounts of crude oil energy currently used in a country like the USA. Even if every bushel of U.S. corn, wheat, rice and soybean were used to produce ethanol, it would only cover about 4 percent of U.S. energy needs on a net basis, estimates Charles Washburn, professor emeritus at California State University in Arizona. (via Bloomberg). Cellulosic biomass presents a potential solution to this problem - it's cheaper, doesn't compete with food crops and estimates have put the level of production from cellulosic biomass as high as 2,000 gallons of renewable petroleum per acre.
All of this can be seen as another link in the chain of technologies we’ll need to break free of mankind’s biggest and most dangerous addiction of modern times.
