You Can Turn E.Coli Bacteria into Microscopic Fuel Factories

At some point in your life, Escherichia coli has probably brought you to your knees to pray to the porcelain god. Common bacteria that often live harmlessly in the guts of most animals, a few strains of it can cause anything from food poisoning to death in humans. But, according to news out of Washington University in St. Louis last month, it may also be the key in our quest to find a renewable, environmentally safe fuel source.

Researchers there recently received a government grant to transform the little pests into miniature waste eating, gasoline-producing factories, theoretically capable of replacing our dependence on fossil fuels. And the Missouri-based scholars aren’t the only or the first to explore the prospect. We’ve been dreaming of an E. coli fuel source for the last seven years at least. This decade of research and experimentation has moved this bio-engineered vision of the future from wishful thinking to an increasingly viable and hopefully imminent reality.

Scientists have long dreamed of using microbes, impossibly common and easily sustained organisms, as miniature factories for churning out organic and synthetic materials. It’s basically modern alchemy—down to the transmutation of gold. But the first to float the notion of using E. coli to create a fuel source were probably the private researchers at LS9 back in 2007. That year they revealed that they had perfected a process for modifying the bacteria’s genes so that instead of producing fatty acids from their food, they would basically shit out hydrocarbon chains, the core components of any fuel. These molecules could then, they hoped, be transformed into gas, diesel, or even jet fuels in a simpler, cheaper, and more energy-efficient process than the production of corn ethanol and a cleaner, safer procedure than crude oil refining.

E. coli isn’t the only bacteria that can produce basic fuel products. In 2011, researchers at Tulane University identified a variety of the often quite nasty Clostridium bacterial genus that could produce butanol, a gasoline equivalent, with relative ease. But most bacteria have problems producing fuels from cheap materials quickly, easily, and reliably enough to be economically viable. E. coli, though, have proven to breed prolifically and have an extremely efficient biosynthetic system, making them ideal for research and mass production.

E.coli, mackonkey agar. Photo by Flickr user Iqbal Osman.

But even with the purportedly perfect miniature processors, LS9 found itself pushing back its rollout dates for test batches and demo plants of E. coli fuel, first to 2010 or 2011, then to 2012 or 2013, then further still. As it turns out, while it’s clear that E. coli have great potential as fuel producers, it’s still hard to grope around for the perfect setting in their genes that will allow them to produce at full capacity, calibrated to work with especially cheap and abundant fuel sources (which they must also learn how to consume).

Researchers like those from the Department of Energy’s Joint Bioenergy Institute, which taught E. coli to eat switchgrass in 2011, and the private Bio Architecture Lab, which have the bacteria munching on abundant seaweed, have toyed with food sources ever since 2007. Meanwhile, in 2013 scientists at Harvard focused on making sure their bacteria would reliably produce hydrocarbon chains roughly equivalent to the fuels we use in our cars, decreasing the cost and time needed to refine their produce. That same year a team at the Korean Advanced Institute of Science and Technology made headlines after they coaxed E. coli into producing a gasoline that could be dumped straight into a car engine and run. But the Korean team could only produce a few grams of fuel at a time; they acknowledge that it will take them a while to become efficient enough that a canister of germs in your garage could replace the gas station.

Even before Washington University’s recent announcement, carmaker Audi announced this year that their own E. coli project was ready to launch test production plants, generating thousands of liters of car-ready fuel. And last month the DoE’s Joint Bioenergy Institute released a few details about their efforts to breed heartier, longer-living bacteria capable of producing more fuel before they croak. The injection of capital into LS9 after their acquisition by the biofuel giant Renewable Energy Group also promises to light a fire under the bacterial fuel world’s ass. And it doesn’t hurt that we now know how to get bacteria to eat shit as well, meaning we now a near-free and infinite food source for our fuel producers if they need it.

All these little revelations over the past decade, and the building breakthroughs of the past year, suggest that, despite the chronic over-optimistic predictions of the biotech field, we may truly be on the verge of a breakthrough in renewable, E. coli-produced fuel sources. Eating plant or food waste as a form of recycling can make bacteria fuel nearly carbon-neutral, as the process takes as much carbon out of the environment as the fuel will put back in. Directly transferable into cars or jets, the newest iterations of the product require almost no refining. Now all that’s left is to keep tweaking until we can get per-unit production up and costs down. But the jumps we’ve already made and the development of test batches suggest that while we may not see it tomorrow, within our lifetimes we’re likely to see a serious test run of E. coli gas. And that will be a welcome future, both for our march towards a fossil fuel-free world and for the reputation of the often maligned but increasingly benevolent bacteria.