During my career as a clinical pharmacist, bacteria and I were NEVER friends. More often than not my patients were infected with some potentially lethal bacterium, and it was my job to provide the magic elixir to eradicate those nasty organisms from their bodies.
So you can imagine my surprise, and interest, to discover that the particularly vicious bacterium Escherichia coli (E. coli for short) is being used to make diesel fuel. My first thought was that it was about time for those malicious, hardy bugs to have a higher purpose.
A recent article in Scientific American explained that scientists have discovered a way to induce E. coli (which normally reside deep in our intestines and aid in food digestion) to produce hydrocarbons that become fuel for big trucks and other powerful machines.
By intricately attaching bits of various microbes and specific parts of the camphor tree into the genetic code of E. coli, the bug changes its primary job of breaking down what we eat to making and replicating hydrocarbon molecules into diesel fuel.
The experiments have been so successful that the diesel fuel products produced could be used directly in existing engines and completely replace fossil fuels. Scientists state that the next step is to develop the bacterium into a more efficient “work horse” that could be deployed industrially.
The E. coli bacterium already is a hardy entity and scientists are working to harness its high tolerance for harsh working conditions (such as the high acidity and warmth of the human digestive tract). That hardiness has already helped the bacterium survive its own production of fuel, an environment that would prove toxic to other microbes.
Currently, the industrial strength E. coli are fed a mixture of sugar and yeast extract, a diet too expensive to make the process financially equitable to the diesel fuel refined from crude oil. But scientists believe that they may be able to fine-tune the genetic engineering of E. coli to use organic wastes from agriculture, and possibly even sewage, as a nutrient. At that point, the process would be feasible and the resulting product would be a suitable replacement for fossil fuels, possibly even replacing jet fuel and gasoline as the process becomes further refined.
Encouraging work at the University of California, Berkeley, to alter E. coli genetics has allowed scientists to produce bacteria that digest the inedible parts of plants (the cellulose parts) and turn them into microbial diesel.
Currently, E. coli is used to make specialty oils for expensive cosmetics. The cosmetic company Amyris makes squalane, a popular moisturizing oil, from bacterium grown in vats in Brazil. The biochemists at Amyris have also produced a special variety of yeast to manufacture an antimalarial drug called artemisinin.
But precious cosmetic oils and specialty drugs are not sold as cheaply as biofuel and that is the challenge in engineering microbes to become industrial work horses to produce economical products that compete with what’s already on the market.
Biotechnology makes monumental advances almost daily, but sometimes it’s still not fast enough to satisfy the possibilities.
Thoughts? Comments? I’d love to hear them!