"My name is Erin Purcell.
I'm a
post doc in the microbiology and Immunology Department at the University of North Carolina
at Chapel Hill.
What I work on here is studying how the intestinal pathogen clostridium difficile which is a
hospital acquired infection senses and responds to changes in its environment.
Well I grew up in Maine.
I really first became interested in science in 9th grade in debate team actually, because
we were given a debate scenario about discrimination against people with genetic diseases, and
I was really, really interested once I got to high school chemistry and was just learning
how stuff works, how the matter in the universe works.
It just kind of blew my teenage mind.
That was what really led me into science.
And then I also wanted to be doing something useful so that led me into studying bacteria
that caused diseases and C. Diff specifically.
C. Diff is, it was actually named as a pun.
Its named clostridium difficile because it's very difficult to work with.
So we actually don't know very much about it considering what an important human pathogen
it is.
It can, it can go dormant and become unstoppable and that's why it persists in environments
for so long, because C. Dif can form these spores.
It produces protein toxins that shred the linings of our intestines and that causes
the bloody diarrhea and sometimes death.
It's people on antibiotics and people who are elderly and immunocompromised who are
really at risk for this disease.
And the CDC recently reclassified it as an urgent threat.
It costs about three billion dollars a year in the US and is implicated in about 29 thousand
deaths a year.
A lot of what I'm doing is now basically poking the bacteria with a little stick and seeing
what happens.
Sometimes it's by knocking out a gene and seeing what it does in response to that external
change.
We are looking at C. Diff in actually two different forms of its life cycle.
If you look here the spores are what's called phase bright, all sort of reflective, and
its very easily distinguished from the long, dark vegetative cells, but the vegetative
cells that they germinate into are the ones that secrete toxins and actually cause symptomatic
infections.
One of the main tools that we use in the lab is that we've built genetic systems to artificially
raise or lower the amount of cyclic di-GMP and because raising and lowering their levels
of cyclic di-GMP One of the main ways they respond to environmental changes and sort
of resist environmental changes, like the changes we cause when we take antibiotics
or change our diets.
When we interfere with their ability to do that we interfere with their ability to survive
changes.
I like to solve puzzles, and I personify the puzzles a little bit so that I have to win
against them.
If my experiments aren't working then, you know, C. Diff is winning.
It's probably not that healthy but it's really motivating.
And just talking things out with other people is very helpful to think, oh I haven't considered
this, or someone else pointing out, have you thought about that?
So that's a really good way to get past roadblocks, talking about the things you like to do and
seeing what other people find the most interesting is a good way to figure out what your priorities
should be for the experiments you're planning.
Everything we find out is something new.
So that is, that's really fun.
You know, on a really good day the human race knows slightly more than it did when it went
to work in the morning and that's incredibly satisfying.
We don't get those everyday or every week, but the good ones are really good.
The big picture is coming up with better treatments for C. Diff.
And the huge picture is coming up with a better understanding of how the bacteria living in
us shape and promote our health and how we can work with that.
I'm in this because I like solving puzzles and getting a little bit obsessive about them
and figuring exactly how they work and then moving on to another puzzle, so I can't really
imagine being satisfied doing anything else."