"A Vision for Microbiology in the Next Century"
Dr. Rita R. Colwell
NATIONAL SCIENCE FOUNDATION
The 99th General Meeting of the American
Society for Microbiology
May 30, 1999
I am delighted to be here this evening. It's a privilege
and a pleasure to serve as your keynote speaker for
the ASM centennial.
I remember my first ASM meeting, when I was a young
graduate student. My advisor, Dr. John Liston, called
me at home the Saturday before the meeting and said,
"I've come down with the flu; you'll have to
give our paper Monday morning."
It happened to be an invited paper, and my fellow speakers
included the late, great Roger Stanier, Michael Douderoff,
and a few other giants.
Well, a few days ago, Stuart Levy called me, and said
in a stricken voice, "Vice President Gore can't speak
at the opening plenary--You'll have to do it!"
You can see that 40 years later history does repeat
Our society is a century old, and we microbiologists
indeed have stunning achievements to celebrate. I
suspect, however, that even more revolutionary changes
are in the offing.
A hundred years from now, we might scarcely recognize
our discipline. That's why I would like to seize this
opportunity to look not behind but ahead--to set forth
the outline of a vision for microbiology in the next
Microbes are everywhere-we've heard them called the
"unseen majority." An estimated 5 million trillion
trillion bacteria live on Earth.
The astonishing abundance of microorganisms, along
with their key roles in biogeochemical processes,
make them essential to the edifice of our knowledge
Microbiology is even taking hold in the public psyche.
We need look no further than our local movie theaters
to see it.
I know a few of you have already braved the long lines
to watch "Star Wars: The Phantom Menace."
The movie introduces us to beings known as "midi-chlorians."
These are microbial entities that live in all of us.
As such, they demonstrate the power of microbes to
unite all life.
This can mean one thing and one thing only. As microbiologists,
the force is really with us.
We need to expand our vision both in time and space.
Ultimately, this vision links biology to all of science
and engineering. Now is the time to inject a new force
into the community.
To illustrate how our approaches must embrace all scales,
from the minute to the massive, I'd like to show you
a very short video clip from the IMAX film titled
The film takes us on a "cosmic zoom" from outer to
inner space. It depicts the unity of our cosmos, and
suggests a framework for future discoveries across
the board. The journey takes us through 42 orders
The links between all aspects of science and engineering,
at all scales, are strengthening all the time.
As John Muir wrote early in our century, "When we try
to pick out anything by itself, we find it hitched
to everything else in the universe."
This sweeping and integrated vision requires us both
to visualize and to envision.
New tools such as information technology help us to
imagine, to see in astonishing new ways--whether
outward into the beginnings of the universe or inward
into the tiniest particles.
New ways of seeing out into the universe--of penetrating
the dust, seeing clearly through the distortion of
our own atmosphere--have propelled astronomy into
a golden age.
Just recently we learned that our universe is expanding
at an accelerating rate, and we're coming ever closer
to putting a number on that rate.
Our goal is nothing short of understanding the biosphere.
Microbiology will play an increasingly central role
as a kind of guiding beacon for biology.
On a grander scale, biology itself will magnify that
role, drawing the other sciences together at its interfaces.
My term for this integrative research strategy is "biocomplexity."
This emerging approach explores the biological and
other interactions in our planet's systems.
To understand biocomplexity, we must gather information
at scales ranging from the sub-atomic to the astronomical.
Let's briefly survey some of the tools and discoveries
that frame this vision.
Today's sophisticated tools help us trace our way back
to our earliest tools. Last month the cover
of Science Magazine featured what appears to
be the earliest evidence, found in Ethiopia, of stone
The antelope bone shows the earliest documented marks
made by human ancestors removing fatty marrow. These
fossils date from 2.5 million years ago.
The site also yielded cranial remains of a new species
of Australopithecus. The tools spurred a dietary
revolution that let human ancestors migrate beyond
Today our tools are taking us on new momentous journeys.
We can take our own cosmic zoom down to the atomic
and molecular levels of matter and of life.
Here we see fluorescent peaks, each letting us follow
a single molecule in a complicated environment--the
environment of condensed matter. This particular image
appeared in another Science Magazine cover
story this past March.
We move to the next level--entire genomes. We sequenced
the first bacterial genome four years ago. Now we
know the entire genomic sequences of 22 organisms--all
but one a microbe.
With microarrays, we can learn about expression of
every gene in a cell or tissue at once.
Understanding protein structure and function at the
genomic level is the next great frontier.
At every step are massive data sets that require tremendous
computing power. Bioinformatics helps us visualize
vast amounts of data at the Protein Data Bank. We're
beginning to be able to trace the flexing and folding
of proteins in the timeframe of nanoseconds.
The data bank exemplifies another welcome trend: interagency
cooperation, between NSF, the National Institutes
of Health, and the Department of Energy.
As our vision broadens to embrace complexity, we discover
new mechanisms in genetics.
In this study of Salmonella genes, researchers from
the University of California-Santa Barbara have found
that the genes turn on inside a mouse, and
The results have broad application to the development
of vaccines and antibiotics.
The gene--called the Dam gene--was actually first found
in E. coli some years ago, through fundamental
research supported by NSF.
Complexity and chaos and other tools of mathematics
are taking biology by storm. We learn anew the old
adage that the whole is more than the sum of its parts.
Complexity in fact draws the disciplines together.
As we move up the organization of life to communities
and ecosystems, the mathematics of complexity help
us to understand the flocking of birds, the schooling
of fish, and the pendulum swings in wild populations.
We find another rich and unexpected reservoir of microbial
diversity in the hindgut of this termite.
It's estimated that termites as a whole contain 2.4
X 1017 prokaryotes. This diversity ultimately
drives the decomposition and recycling of our forests.
Here we focus in on the termite's hindgut region showing
the density of the protozoa, which contain unique
genera and species.
Complexity likewise helps us approach the myxobacteria.
This group is found all over the world and functions
as a predator in the soil ecosystem.
Myxobacteria stand out for their surprisingly social
behaviors such as rhythmic rippling and production
of fruiting bodies.
Recently, a compound was found in a myxobacterium that
shows promise as a cure for certain cancers.
As we move up to the ecosystem level, we find a major
piece missing: knowledge of the role of microbes.
NSF has a new program to support study of microbial
diversity at established research sites. These include
our Long-term Ecological Research network, other laboratories,
and field stations.
This week's cover story in Science Magazine highlights
biofilms--a superb illustration of a new and comprehensive
approach to microbiology.
The lead author is Bill Costerton from the Engineering
Research Center at Montana State University.
We're learning that microbes act much differently in
nature than when isolated in laboratory culture.
It's true that we've known about the slimy films formed
by bacteria ever since Antonie van Leeuwenhoek first
looked at plaque from his teeth beneath his early
But only collaborative research has revealed the true
nature of biofilms--as they really are microbial societies.
Knowledge about biofilms has a wealth of applications,
from dentistry to heart surgery to wastewater treatment.
The CDC implicates biofilms in 65% of human bacterial
infections. That's a revelation.
State-of-the-art imaging tools let the research team
see the bacterial architecture: mushroom-shaped towers
with channels to transport waste and water. It's a
primitive social community, if you will.
Such studies spawn a new perspective. Instead of trying
to eradicate microbes, we'll attempt to manipulate
and engineer their behavior.
Other information technologies are helping us to see
and to collaborate across the country. Researchers
from Old Dominion University in Virginia link up with
the National Center for Supercomputing Applications
at the University of Illinois.
This "virtual environment" is constructed from actual
Chesapeake Bay data. Collaborators thousands of miles
apart can interact in this same virtual arena.
At another NSF facility, the San Diego Supercomputing
Center, there's another way to visualize. When virtual
reality is not enough, we can produce solid models
that look and feel like wood.
This new way of seeing offers a tool for all disciplines.
Here, the hands are holding a model of a protein called
Seeing on a grander scale--seeing the Earth from satellites--has
been key to my own research on climate and health.
Remote sensing of sea surface temperature and sea surface
height has helped us to trace the ecology of the bacteria
that cause cholera.
Microbiology is forging new frontiers at all scales.
We're finding life everywhere. Subsurface microbes--those
below the ocean or under the earth's surface--could
constitute up to half or even more of the biomass
of the planet.
These huge numbers suggest a great capacity for mutation
and genetic variation.
Let's visit a few of these frontiers to meet our fellow
travelers. In South Africa, at more than 3 kilometers
down into the Earth, researchers from Princeton University
found a veritable zoo of types of microbes, some of
which are in biofilms.
At these depths, thermophilic and other microbes were
found in rocks 2.9 billion years old.
Evidence of microbial activity has been found in oceanic
basalts by a team including Steve Giovannoni of Oregon
Surveys suggest that bacteria have colonized much of
the upper crust under the ocean.
Antarctica is another frontier yielding life in abundance.
In the region there known as the Dry Valleys, lakes
have permanent ice-covers.
Tiny oases of life pit these ice blocks, which were
carved from two meters down. Here we find nutrient-rich
microzones for a "microbial consortium," according
to John Priscu from Montana State University and his
One of the lakes--Lake Bonney--yielded this cyanobacterium,
stained red and blue, which fixes atmospheric nitrogen.
In a far different environment, beneath the East Antarctic
ice sheet, lies Lake Vostock, the largest sub-ice
lake known to exist.
This relief map of Antarctica's ice topography, derived
from satellite data, shows the lake's location. The
lake water is estimated to be one million years old.
We expect it to contain ancient bacterial life.
The challenge now is to design a probe that could sample
the lake without contaminating it.
Besides revealing life in unexpected places, Antarctica
serves as a model for exploration of life beyond Earth.
Here is Europa, Jupiter's icy moon. Now a dream, but
perhaps not far off, is an attempt to join the disciplines
to search for evidence among the stars that an explosion
of diversity might have occurred elsewhere in space
We're exploring the promise of Europa, where liquid
water seems to lie below the surface.
The surface of Mars is pictured here in black-and-white
next to the Mississippi River, which is in red. Mars
may once have harbored liquid water as well.
To explore the tremendous biocomplexity of our planet
and beyond, we'll need to collaborate on every front,
with every discipline and at every scale.
Information technology will speed our search in the
coming century--taking us places we could never reach
by remaining inside our own disciplines.
To realize this vision is not going to be easy. A great
irony of our current era is that as a nation, we have
let research investments wither--just as the payoffs
Over the past two decades, we have seen science and
technology drive job growth and creation.
This reminds us that educating our future work-force
belongs at the forefront of our vision. We've also
seen "high-tech" products double as a share of total
At the same time, we've seen the Federal investment
in R&D fall as a share of our economy. To me that
defines what it means to eat your seed corn.
We're ready to do 21st century science.
Now we need 21st century investments to
go with them.
We're on our way. Our cosmic voyage through the various
scales of life has one more stop. I would like to
show you life at one more frontier--a brief video
of microorganisms issuing forth from rocks on the
This footage was provided by John Baross from a dive
on the Alvin submersible.
We're looking at organic "floc" material issuing from
an undersea vent along the Juan de Fuca Ridge, about
250 miles off Washington State.
The patterns of material spewing forth recall our trip
across the orders of magnitude, from quarks to stars.
These geothermal vents are called "snowblowers" for
There are microorganisms associated with the floc material,
including ones that grow in temperatures above 90
This is more evidence that we've barely begun to explore
the diversity of life beneath the surface of our own
planet. Could this material be coming up from the
depths of the earth's mantle?
That's another puzzle for the next century that will
take all of our capabilities to solve.
Many capabilities and contributors produced the work
I've discussed, and this list is not complete. I regret
not being able to name everyone, but I thank you all.
Collectively, we are more than the sum of our parts,
and together we can see much farther. The philosopher
Pierre Teilhard de Chardin summed up the ability of
science and engineering to refine our vision when
"The history of the living world can be seen as
an elaboration of ever more perfect eyes within
a cosmos in which there is always something more
to be seen." [The Phenomenon of Man, 1955].
Let me close by saying that I look forward to working
with all of you to fulfill this vision of microbiology--and
science--for the next millennium.