What do Yellowstone National Park and Beer Have in Common?
A unique bacterium first uncovered in Yellowstone is helping brewers quickly test for contamination.
An Important Discovery in Yellowstone
The thermus aquaticus bacteria were first discovered in the Lower Geyser Basin of Yellowstone National Park. Thanks to a heat-stable enzyme within the bacteria, the Taq polymerase enzyme, these organisms can live in extremely hot temperatures (upwards of 99 degrees Celsius), whereas most bacteria cannot survive in temperatures over 60 degrees Celsius. The amazing colors that ring the scalding hot springs and geothermal pools are thanks to varying kinds of these bacteria.
In the late 1980s Nobel Prize winning scientist Kary B. Mullis developed the Polymerase Chain Reaction (PCR) using the Yellowstone Taq enzyme. Kary multiplied a small quantity of DNA into thousand or millions of copies to identify the presence of a known DNA. This method of testing uses repeated cycles of heating and cooling, much like the conditions in a hot spring or geyser; often, the heating and cooling cycles are repeated 30 to 40 times.
The Uses for This Kind of Testing are Far-reaching
Medical tests using the Yellowstone enzyme include diagnosing diseases such as cancer, paternity testing, and detecting genetic relationships between individuals, such as parent-child or siblings. The high sensitivity of PCR can detect infections sooner, and even before the onset of disease. It can also target multiple things at once, meaning a single test can do what used to require multiple tests. PCR quickly became such a valuable method of biological testing that scientists started creating the Taq enzyme in a lab.
Today that Enzyme and PCR are Starting to be Used to Test Beer
The brewing process is highly controlled to ferment with only the desired yeast -- and to keep out all bacteria. To check for contamination, conventional methods can take two days to determine if there is a contaminate, and another two days to determine what the contamination is; with PCR you can determine the if and what in two hours. These speed gains mean that a brewery can test more beer in less time, and deliver a more consistent high-quality beer to consumers.
So the next time you enjoy a tall one, give a little toast to the teeming Yellowstone ecosystem that make your suds a little tastier.