Written by: Richard Lenski
Primary Source: Telliamed Revisited
My research is funded by the National Science Foundation, including the BEACON Center for the Study of Evolution in Action. BEACON is one of a dozen or so NSF Science and Technology Centers. Today, our Representative in the US Congress, Mike Bishop, came to BEACON for 40 minutes to discuss our center—what we do, what impacts our work has, and so forth.
It was something of a “fire hose” for Mr. Bishop, with several presenters trying to convey a lot of information very quickly. However, he was engaged and asked thoughtful questions. I think he left with an understanding of the importance of scientific and engineering research, including how fundamental curiosity-driven research can lead to applications.
I had 10 minutes to show him my lab and explain what we do and why. When I make a short presentation like this one, I often write out a version in advance. I don’t read it or memorize it by any means. However, writing it out helps get my thoughts in order—removing details that aren’t important, ordering ideas into a narrative, reminding me of what I most want to convey.
I’m sure I was not as clear or coherent as the text that follows. I offer it here because it conveys the points I tried to make in the few minutes that I had as a representative of science speaking with a representative of the people.
I want to show you one of the experiments in my lab. We call it the long-term evolution experiment. It’s an unusual experiment because it’s been running for over 27 years. And we keep it going because it’s been a scientific goldmine leading to new discoveries about how bacteria change over time.
It’s important that we understand bacteria and how they evolve for many reasons. Bacteria are best known because some of them can cause dangerous infections. But many of them protect us against infections—if our guts were not filled with harmless bacteria, then the dangerous ones would have a much easier time getting established in our bodies. Some bacteria also provide nitrogen to plants and perform other essential functions in the environment, including degrading some of the wastes that we produce. And some bacteria are the workhorses of biotechnology.
To give one example of why bacterial evolution is so important: If bacteria didn’t evolve, we would have defeated nearly all the pathogenic bacteria on Earth with antibiotics. But they do evolve and become resistant to our drugs, and so the pharmaceutical industry has to spend billions of dollars trying to keep up with the evolving bacteria and viruses by developing new drugs to treat infections.
It’s possible to see evolution-in-action in bacteria, like we do here, for several reasons.
- Their populations are huge. The number of bacteria in just one of these little flasks is comparable to number of people in the United States.
- They grow really fast. Every day, there are about 7 generations of bacteria in each of the flasks. So each day we see the great-great-great-great-great grandkids, so to speak, of the bacteria that were in our flasks yesterday. After 27 years, the experiment has run for over 63,000 generations.
- And one more important thing about bacteria. We can freeze them and bring them back to life, and so we’ve got a frozen fossil record of the experiment.
When I started the experiment in 1988, there was no human genome project, and not even a single bacterial genome had been sequenced. Now we go into our freezers and sequence the bacterial genomes to see how their DNA is changing over time.
The work we’ve done in this curiosity-driven experiment has inspired others who are using similar ideas and approaches to understand the rates and mechanisms of how bacteria evolve.
I’ll give two quick examples that show how our NSF-supported fundamental science gets translated into applications that are important for security and health.
First, you remember the anthrax letter attacks on Congress that occurred right after the 9/11 attacks. In the first few days after the anthrax attacks, I was contacted by the Defense Threat Reduction Agency for advice on how to identify the source of the strain used in that bioterrorism, and how to distinguish it from other related strains. And in the months that followed, I was asked for and provided advice to the FBI and other agencies investigating the attacks. Tracking the source of microbes in outbreaks—whether natural or terroristic in origin—requires understanding how they change over time.
Second, my colleague Prof. Martha Mulks studies bacteria that colonize the lungs of people with cystic fibrosis (CF). There are about 30,000 people with this disease in the US alone. It’s an inherited disease that makes people susceptible to lung infections and, unfortunately, those infections kill many kids and young adults with CF. Some of the bacteria that infect the diseased lungs are not pathogens to most of us—they’re bacteria that live in soil and on plants, but when they get into the lungs of CF patients they evolve and adapt to that new environment. They also evolve resistance to the antibiotics that are meant to get rid of them. How exactly the various bacteria change to become better adapted to the CF lung environment is not known. Luckily, though, Martha Mulks and other foresighted scientists and clinicians have kept frozen samples of these bacteria over the years—just like we’ve done with the long-term experiment I described a moment ago. Now the BEACON Center is supporting work by a graduate student, Elizabeth Baird, who will analyze the DNA from old and new samples and apply some of the same approaches and methods that we’ve used and developed for the laboratory experiment to see how the bacteria have changed—how they have become resistant to antibiotics and otherwise adapted to the environment of the lungs of people who suffer from cystic fibrosis.
The bottom line is that the fundamental, curiosity-driven research that the National Science Foundation supports is also an engine for future applications—often ones that we may not even have dreamed of—as well as a training ground for the talented and dedicated young people who you can see working all around us in this lab and throughout the BEACON Center.
Rep. Mike Bishop (MI-08) and me in the lab. [Photo: Danielle Whitaker, MSU.]