Going to Extremes

Extremeophilic microbes have learned how to deal with near-boiling temperatures and other brutal conditions. To microbiologists, that makes them fascinating—and useful.

By Nicole Miller

ON THE ICY BOARDWALK ABOVE BLACK POOL, Tom Schoenfeld is working as fast as his numbing fingers will allow. He lowers a hose into the steaming pool, one of dozens of hot springs in the West Thumb portion of Yellowstone National Park, and then slides the other end into a keg-sized plastic jug. Shuffling along the slick wood planks, he begins piecing together the rest of the water filtration system that he developed for Lucigen Corporation, a Madison-area biotech company where he is vice president of enzyme discovery. The system, which concentrates the bacteria and viruses living within the spring, takes about 30 minutes to set up and an additional two hours to produce a couple of liters of teeming liquid. And though Schoenfeld arrived here at the break of dawn on this freezing September morning, he barely has enough time to get his work done before the tourists arrive. Tourists always delay things.

Researchers who study extremeophiles are partly motivated by curiosity, but also by the realization that extreme forms of life, like high-endurance athletes, have extraordinary abilities.

Despite its name, Black Pool is gemstone blue and perfectly clear. Its scalding waters produce a thick steam that rises from the pool and floats across the boardwalk, enveloping Schoenfeld in a fine mist. Water droplets soak his clothes and frost his eyelashes. As he reaches to switch on the generator that powers his equipment, he hesitates. There’s water all over it-and on the electrical cords leading to the pumps.

“Wear your gloves when you turn that on, man,” says David Mead, Lucigen’s president, who has accompanied Schoenfeld on seven visits to Yellowstone’s hot springs. As much as they can, the two look out for each other in the field and so far so good. Neither has been electrocuted, and they hope to keep it that way.

Electric shock, however, is only one of many perils they face collecting biological samples from Yellowstone’s springs. Once, a herd of unruly bison flushed the researchers from the edge of a backcountry pool, forcing them to wait several hours before they could return to collect Schoenfeld’s equipment. Another time, hiking through a dense forest, Mead tripped and narrowly missed impaling himself on the jagged branch of a downed tree. But above all else, they worry about the hot springs themselves. According to the book Death in Yellowstone, at least 19 people have died after falling or jumping unwittingly into the park’s pools, which are heated by an underground volcano. And as the book relates in sometimes gruesome detail, no matter how quickly a person scrambles out, falling into near-boiling water is a death sentence.

But for Schoenfeld and Mead, these risks are worth taking. That’s because they believe there are million-dollar microbes living in the park’s pools-bugs that, if found and studied, could unlock the doors to major medical breakthroughs and biotechnological advances. And if history is any guide, the bugs are almost certainly there, surviving and thriving in conditions that would kill almost any other form of life.

All Schoenfeld and Mead have to do is find one of them.

Welcome to the adventurous world of extreme microbiology. Like hundreds of other research scientists, Mead and Schoenfeld travel to Yellowstone to seek out extremeophiles-microorganisms that thrive in extremes of temperature and pressure and other inhospitable environments. These bacteria and viruses survive not only in hot springs but in metal-contaminated soils, pools of acid and lakes so salty that crystals bejewel the shoreline. The researchers who seek them out are partly motivated by curiosity, but also by the realization that extreme forms of life, like high-endurance athletes, have some extraordinary abilities. They harbor powerful proteins-known as enzymes-that enable them to make the most of their surroundings, efficiently turning otherwise inaccessible materials into the food and energy needed to sustain life.

“The bottom line,” explains UW-Madison microbial geologist Eric Roden, who teaches an undergraduate course on extremophiles, “is that extremophiles can do things that other organisms can not.”

Scientists first stumbled onto these rare organisms just a half century ago, when microbial ecologist Thomas Brock, then a professor at Indiana University, found a type of bacteria living in Yellowstone’s Mushroom Spring. Brock, now an emeritus professor of bacteriology at UW-Madison, had been searching for an ecosystem hot enough to support only a few forms of life. On a field trip to Yellowstone in 1964, he began examining the spring’s outflow channel. Starting at the cool end of the channel, where a lush, colorful mat of organisms covered the streambed, he worked his way up to hotter and hotter sections.

“When I got up close (to the spring), I started seeing this stuff,” says Brock, who joined the UW-Madison faculty in 1970. “It didn’t have any pigments. It didn’t have any chlorophyll or anything like that, but it looked like it was alive.”

And it was. Brock was able to grow and study this “stuff” in the lab, and in this way discovered the first extremophile, a heat-loving bacterium he named Thermus aquaticus, which is capable of growing at temperatures up to 80 degrees Celsius, not far below the boiling point of water. (Later, it was discovered that T. aquaticus lives in most residential hot water heaters, a harmless squatter.)

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Posted in Energy, Featured, Spring 2009 | 4 Comments »

4 Responses to “Going to Extremes”

  1. Posted by: Bill | March 20th, 2009 at 9:38 pm

    The writer of this article has many relatives that couldn’t find their rear end with both hands as it relates to science. But in this case she made this article, informative, interesting and readable. Isn’t science something that should be left up only to US Senator un-Inhofe from OK? But, that is another story.
    I have read other articles written by Nicole Miller that are equally on target and I would expect nothing less from her. So relatively speaking Nicole did a great job.

    Still snowing on Stevens Pass this afternoon as we drove back from the coast.
    Keep up the good work.
    Uncle Bill

  2. Posted by: Kathi | March 21st, 2009 at 6:26 am

    The fishing and prospecting analogies bring to mind the sad state of our fishery and mining industries. In the (perhaps distant) future, will we be fighting to clean or save the last of these bioprospecting sites? I worry that we’ll repeat history and deplete yet another natural resource. Especially with such big money at stake, it’s not always easy to keep practices sustainable. I hope someone, in this developing stage, is concerned about conservation and sustainability.

  3. Posted by: Sevie Kenyon | March 26th, 2009 at 11:49 am

    Bio-prospecting in a public park. Isn’t there a controversy about that?

  4. Posted by: Susan Mills, Environmental Protection Specialist, National Park Service | April 7th, 2009 at 9:40 am

    I’m a National Park Service (NPS) employee stationed in Yellowstone National Park, and I work very closely with the bioprospecting issue at the national level. First off, let me say it’s very gratifying to read your comments expressing concern for protecting the natural environment. Speaking for the National Park Service, we absolutely agree that park resources and values must not be harmed by these activities. We take our mandate, handed down by Congress, to preserve park resources “unimpaired for future generations” very seriously.

    On a practical note, bioprospecting today is very high-tech. It’s a search for useful knowledge, not a search for useful raw materials. In NPS areas, these types of “bioprospecting” activities are only allowed if a researcher’s proposed project first qualifies for an NPS research permit. All NPS research permit applications receive a thorough environmental review, and permits are only issued if the proposed research activities are determined to be acceptable under the NPS’s long-standing Scientific Research and Collecting Permit protocols. These protocols set out firm requirements that researchers must satisfy and afford strict protection provisions for all National Park resources. Unlike mining or commercial fishing, bioprospectors in NPS areas can only remove small samples used for research; park research cannot supply raw material for industry. NPS research permits do not authorize extractive activities such as harvest, use or sale of NPS natural resources, “biomining,” logging, or any kind of mining or comparable activities. Additionally, no harvest of natural resources could occur under the guise of “research” because the resource protection provisions of NPS regulations would not allow it, and NPS Management Policies reinforce these provisions. For more information about the requirements for NPS research permits, please see https://science.nature.nps.gov/research/ac/ResearchIndex.

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