Profile of Rick Colwell, new SBI faculty member in the
College of Oceanic and Atmospheric Sciences
Posted: June 1, 2006
The Subsurface Biosphere Initiative would like to welcome Dr. Rick Colwell,
a geomicrobiologist who will join the faculty of the College of Oceanic
and Atmospheric Sciences (COAS) in June 2006. Rick has been a scientist
at the Idaho National Laboratory (INL)
since 1986 where his research has focused on microbial communities in
subsurface environments. Rick’s position is in part funded by the
Subsurface Biosphere Initiative and we are delighted about the expertise
he brings to campus.
Below is a short interview designed to introduce Rick. Please contact
if you would like more information about his research – he is excited
about the potential for new collaborations at OSU.
Photo of Rick working with
a multi-level sampler used to characterize the aquifer chemistry
and microbiology at the Idaho National Laboratory's Test Area North.
This is a site where Colwell and his collaboartors are studying
TCE co-metabolism by methanotrophic microbes. (Photo by Sean O'Connell.)
How did you become interested in geomicrobiology and the subsurface
I became interested in working in this field through my early experience
at the Idaho National Laboratory. In
the late 1980s the Department of Energy sponsored research to explore
the subsurface biosphere. The program manager of this Subsurface Science
Program required interdisciplinary collaboration among investigators in
order to answer complex questions related to these deep geological environments
and thereby broke the traditional language and context barriers that divide
disciplines. It became clear to me that microbiological studies of these
habitats needed to integrate an understanding of the physical and chemical
environment in which the organisms grow. I also became intrigued by the
difficulties of studying microbes from the subsurface; it is strikingly
heterogeneous and actually quite remote despite the fact that the habitable
subsurface is not far beneath us. Even the task of collecting representative,
uncontaminated samples from the deep earth became an exciting challenge
that prompted close teamwork.
What motivates your research?
I enjoy studying unique microbial habitats, the microbes in those habitats,
and trying to work out what controls their survival in those locations.
My goal is to understand how integrated microbiological systems function.
When possible, I like to work iteratively with modelers – my research
and experimentation helps to determine realistic input variables that
the modelers need to accurately describe the system. Together, we hope
to develop a better understanding of the system that can improve our ability
to predict how microbial activities matter in a selected environment.
For example, an exciting current collaboration is my work with Jerry
Dickens, a climate change modeler at Rice University and Bill Ussler,
a geochemist at the Monterey
Bay Aquarium Institute. Together, we are interested in the amount
of methane produced by methanogens in deep marine sediments, what controls
the rates of methanogenesis, and how that biogenic methane factors into
the global carbon cycle. Our methanogenic rate experiments with a methanogen
from the seafloor sustained under conditions representative of deep sediments
aim to provide data for Jerry’s carbon cycling models and our experimental
parameters (e.g., pressure, temperature, methane concentration) are framed
by Bill’s thermodynamic calculations.
I also like the exploratory aspects of geomicrobiology. It is undeniably
exciting to puzzle out the identity, activity, and constraints of a microbial
community that has not been described. The research starts out with basic
questions such as, “What organisms are present? Where do they exist?
What are they capable of?” Later, we move to hypothesis driven experimentation.
Transmission electron microscope
photo of Methanoculleus submarinus. This new species of
methanogen was captured from sediments 246 m below the seafloor
in the Nankai Trough off the coast of Japan and is being used in
Rick's methanogenesis rate experiments. (Photo by Henry Aldrich.)
Are you doing anything else related to the microbiology of methane
hydrates -- the ice-like substance that traps methane in sea floor
In addition to the methanogenic rate experiments and modeling we are
also investigating the small scale control that methane hydrates or other
seafloor sediment characteristics have on the type and numbers of microbes
in the sediments. For this work I am a part of a team with Marta
Torres (OSU professor of Chemical Oceanography) and we will be receiving
new hydrate samples this summer. The samples will come from closely spaced,
deep marine sediments obtained from off the coast of India and will compare
the microbial community, geochemistry, and sedimentology of sediment layers
that contain methane hydrates with layers that don’t. The goal is
to better understand the microbial distribution in and around methane
One of your research projects focuses on TCE contamination at the Idaho
National Laboratory. Can you describe it?
A portion of the aquifer at the INL is contaminated with TCE, a common
groundwater contaminant that was once used as a cleaning agent. The TCE
is gradually disappearing from the aquifer by natural means and we have
good evidence that this disappearance is due, in part, to the activity
of methane-consuming microbes (methanotrophs). Interestingly, methane-producing
microbes also in the groundwater seem to sustain this process. The EPA
and the Idaho Department of Environmental Quality have accepted “monitored
natural attenuation” as the most appropriate cleanup solution for
part of this contaminant plume. In other words, the system is cleaning
itself up and the process only needs to be monitored over time. But the
complete story regarding the cleanup is still not known. We don’t
know the rates at which the methanotrophs co-metabolize or destroy the
TCE nor do we have a clear idea of what factors control this activity.
I am working on a project funded by DOE Office of Science that is trying
to understand the system better. We are placing reactors into the aquifer
where we can control aquifer flow rate and methane availability and we
want to derive in situ rates for the cometabolism of TCE. We will also
take samples of the microbial community and work with them in the lab
to model TCE transformation, look at gene expression, and the production
of particular proteins that are unique to methanotrophs. Another collaborator
will use heavy isotopes to trace the path of methane, the microbe’s
food source, in the system. When integrated, we hope this research will
provide a systems level of understanding of the methanotrophs in the aquifer
and how biological and abiological processes are coupled.
Rick is also an enthusiastic
fisherman and soccer player. He caught this Yellowstone cutthroat
on the Gros Ventre River near Jackson, WY last summer. (Photo by
What are you looking forward to about coming to OSU?
I’m excited about the community – this is really a thriving
environment for the type of collaboration and interdisciplinary work I
like to do. There are few places in the country that have this collection
of scientists and I’m excited for the chance to work with people
in different disciplines related to earth science and geomicrobiology
– from waste degradation, to methane hydrates, to fine-scale colonization
of geological materials, and maybe hydrogen production. At the same time,
I hope to continue my collaborations with researchers at the Idaho National
Laboratory and at other national labs and I hope to bring opportunities
to OSU by helping to be a bridge to those institutions. For example, I’d
like to encourage students to consider research projects that would include
internships at the INL. Such internships would benefit the scientists
at both institutions.
What types of teaching will you do at OSU?
At INL I worked with some students, for example summer interns, but I
didn’t have the opportunity to work with students as extensively
as I will here. I am really looking forward to exploring ideas with them.
I plan to supervise graduate students and look forward to developing a
lab team that will hopefully grow to include one or more post-docs and
undergraduates as well. I will also teach one class a year in COAS –
perhaps a geomicrobiology class since that’s my area of expertise.
I hope a class like this will be useful to an interdisciplinary group
of students, for example students who are in the IGERT
Earth's Subsurface Biosphere Program.
Rick arrives on campus in late June and can be reached at email@example.com.
To learn more about geomicrobiology and the Idaho National Laboratory,
he also suggests visiting the following web pages: