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The Good News
2015 November
Pg 3 - The Sunshine Express
Down to earth applications
In addition to astronomy, the DWLS has found use in
creating geometric phase holograms for use in mobile
displays, holographic imaging, and remote-sensing
devices for everything from satellites to cameras. One
high-profile application was the visually impressive
¡°Rainbow Station,¡± an art installation conceived by Daan
Roosegaarde and designed in partnership with Snik for
the International Year of Light.
¡°Light is everything in astronomy,
it¡¯s the carrier of almost all
information and knowledge we
have of the universe,¡±
- Frans Snik, astronomer, Leiden University
Escuti is continuing to work on new applications with
direct support from the National Science Foundation
and the Jet Propulsion Laboratory, and in partnership
with fellow NC State faculty member Michael Kude-
nov on projects supported by the National Institutes of
Health, the Department of Energy and the Department
of Defense. But he has also taken steps to commercialize
the technology by integrating it into devices for specific
market applications.
For example, Escuti¡¯s university startup company, Ima-
gineOptix Corporation, has created technologies ranging
from an ultra-efficient pocket projector the size of a few
quarters to components for active photonic hardware
supporting internet traffic.
¡°As an entrepreneur, I¡¯m excited by the wide range of
projects and markets where we can have an impact.
That¡¯s important to me,¡± Escuti says. ¡°As a researcher,
I¡¯m deeply satisfied by the capability of the DWLS to
help people solve longstanding research challenges. At
least a dozen times in the last few years, my scientific
and engineering peers have told me: ¡®You¡¯ve done some-
thing we didn¡¯t think was possible.¡¯ That¡¯s a tremendous
feeling.¡±
(source: Matt Shipman, North Carolina State University,
www.nsf.gov/discoveries)
sophisticated in their social interactions and
communicate with one another through
similar electrical signaling mechanisms as
neurons in the human brain.
In a study published in this week¡¯s advance
online publication of Nature, the scientists
detail the manner by which bacteria living in
communities communicate with one another
electrically through proteins called ¡°ion
channels.¡±
¡°Our discovery not only changes the way we
think about bacteria, but also how we think
about our brain,¡± said G¨¹rol S¨¹el, an asso-
ciate professor of molecular biology at UC
San Diego who headed the research project.
¡°All of our senses, behavior and intelligence
emerge from electrical communications
among neurons in the brain mediated by
ion channels. Now we find that bacteria
use similar ion channels to communicate
and resolve metabolic stress. Our discovery
suggests that neurological disorders that
are triggered by metabolic stress may have
ancient bacterial origins, and could thus
provide a new perspective on how to treat
such conditions.¡±
¡°Much of our understanding of electrical
Hologram Technology (continued from page 1)
When a biofilm composed of hundreds of
thousands of Bacillus subtilis bacterial cells
grows to a certain size, the researchers discov-
ered, the protective outer edge of cells, with
unrestricted access to nutrients, periodically
stopped growing to allow nutrients, specifically
glutamate, to flow to the sheltered center of
the biofilm.
In this way, the protected bacteria in the col-
ony center were kept alive and could survive
attacks by chemicals and antibiotics. Realizing
that oscillations in biofilm growth required
long-range coordination between bacteria at
the periphery and interior of the biofilm, to-
gether with the fact that bacteria were com-
peting for glutamate, an electrically charged
molecule, prompted the researchers to specu-
late that the metabolic coordination among
distant cells within biofilms might involve a
form of electrochemical communication.
The scientists noted that glutamate is also
known to drive about half of all human brain
activity. So they designed an experiment to
test their hypothesis. The object was to care-
fully measure changes in bacterial cell mem-
brane potential during metabolic oscillations.
The researchers observed oscillations in mem-
brane potential that matched the oscillations
in biofilm growth and found that ion channels
were responsible for these changes in mem-
brane potential. Further experiments revealed
that oscillations conducted long-range electri-
cal signals within the biofilms through spatially
propagating waves of potassium, a charged
ion. As these waves of charged ions propa-
gate through the biofilm, they coordinated
the metabolic activity of bacteria in the inner
and outer regions of the biofilm. When the ion
channel that allows potassium to flow in and
out of cells was deleted from the bacteria, the
biofilm was no longer able to conduct these
electrical signals.
¡°Just like the neurons in our brain, we found
that bacteria use ion channels to communicate
with each other through electrical signals,¡± said
S¨¹el.
(continued on Page 4>>>)
Biologists Discover Bacteria Communicate
Electrically; Discovery changes how we think
about bacteria and also our brain
Biologists at UC San Diego have discovered that bacteria,
often viewed as lowly, solitary creatures, are actually quite
Bacteria Mystery Solved
signaling in our brains is based on struc-
tural studies of bacterial ion channels¡±
said S¨¹el. But how bacteria use those
ion channels remained a mystery until
S¨¹el and his colleagues embarked on an
effort to examine long-range communi-
cation within biofilms, organized com-
munities containing millions of densely
packed bacterial cells. These communi-
ties of bacteria can form thin structures
on surfaces, such as the tartar that de-
velops on teeth, that are highly resistant
to chemicals and antibiotics.
The scientists¡¯ interest in studying long-
range signals grew out of a previous
study, published in July in Nature, which
found that biofilms are able to resolve
social conflicts within their community of
bacterial cells just like human societies.