Microbe Management

A UNLV professor searches the state’s hot springs for a new source of energy

Nevada could be a breeding ground for the next biofuel, according to researchers. Look no further than the 400 or so natural hot springs across the state. And if you are, indeed, looking, take a microscope, because the critters that researchers are after are the teeny tiny organisms and enzymes that thrive in the heat of the hot springs. More than 10,000 of them could fit in the palm of your hand.

Microbiologist Brian Hedlund, an associate professor at UNLV, is studying a variety of microorganisms to find out which ones can most efficiently convert waste into energy. He’s looking for bacteria that are the fastest and best at consuming cornhusks and pooping ethanol—or, to put it more scientifically, converting cellulose to simple sugars. This, he hopes, will one day lead to a second-generation biofuel.

Before we get too far into second-generation biofuel, let’s take a look at first-generation biofuel, such as ethanol, which is used as a gasoline additive or even as fuel. Ethanol is an alcohol created by fermenting corn. But ethanol made from corn is controversial, because the raw material is food that could go to feed people, or animals, instead of powering cars. Using valuable land to grow fuel for cars has some people questioning the ethics of ethanol. This is what’s known as the “food versus fuel” issue.

Now, a number of labs, academics and corporations are working toward second-generation biofuels, where waste (corn cobs, corn stalks, corn husks, etc.) rather than edible food, is converted to fuel. The problem is that waste, like a corncob, is more difficult to convert to fuel than a kernel of corn. That’s where the heat-loving (thermophilic) microbes found in Nevada’s hot springs come in.

“The idea is if you carry out these reactions at a higher temperature you need less water, things are faster and the enzymes tend to last longer,” Hedlund says. “And plus, actually there’s another possible goal that some of these microbes actually directly make ethanol or other fuels. And if you carry this stuff out at high temperature, the ethanol just boils off. You can collect the ethanol all in one step.”

Hedlund is working with researchers from the Desert Research Institute and Lucigen Corp., a private research firm located just outside of Madison, Wisc., to find out which microbes work best. He says it could be years before they know the answer.

In the meantime, he doesn’t just work with Nevada hot springs. Hedlund recently received a $3.75 million grant from the National Science Foundation to work with seven other U.S. universities and six Chinese universities to study Tengchong, the largest geothermal springs in China. It’s the largest research effort of its kind.

Hedlund knows that it will take years of research and millions, if not billions, of microorganisms to test before fully decoding the capabilities of hot springs organisms. And of course, microbes are certainly not the only option, when it comes to fuel.

“There are many, many possible solutions to the energy crisis, and this is only one of them,” he says. “There’s a lot of hope for wind energy and solar energy, and it’s a complex problem and it’s probably going to be a complex set of solutions.”Ten thousand of those solutions might even be in his hand right now, as he speaks.