My lab has been interested in
photosynthesis for many years and the
reason we were interested in
photosynthesis is that the organisms
that take
sunlight and transform them into
chemical energy this is photosynthesis
Green algae, cyanobacteria and plants
they do an amazing thing one of the most
important things however is that these
organisms they know how to protect
themselves
Many times the light is just too strong
and if it is illuminated too strongly
they'll just die of too much light so
they have to find a way to protect
themselves
It was believed for many years that a
certain protein is able to protect from
over excitation by having a certain
molecule come in close proximity to
other molecules that's what was believed
In our study which was recently
published what we found is that this
protein instead of bringing the molecule
in proximity
it actually burrows itself into what we
call an antenna protein the antenna
proteins just like a regular antenna for
a TV which collects waves but it
collects the sunlight and takes all of
this energy and pumps it into what we
call the reaction center that's where
photochemistry happens
What we found is that this one protein
it actually burrows itself in it opens it
up and by opening it up it's like
disconnecting a cord and now instead of
the energy flowing into the reaction
center and burning it
it flows out as heat and the cyanobacteria that we work with protect
themselves and when the light goes down
this protein comes out and the energy
starts flowing back into the reaction
center
Basically this is a molecular switch It's
a true molecular switch Just like a
switch at home which you can flip on and
flip off and what's doing the flipping
here is a protein which understands how
much light is being hit at any one time
We have many goals in the lab when we
research photosynthesis
We are interested in the basic science
of understanding how evolution brought
about these fantastic mechanisms which
are able to deal with such changing
environments but on the other side
we also have interest in making life
better and making life better means a
way to make clean energy and clean
energy in the
end the best way to do that is to use the
sun sunlight Now
sunlight is sometimes very weak and
sometimes very strong when it's very
weak
the solar cells that we have today are
very inefficient because they were
developed for high light
We think that we can use the same types
of mechanisms developed in organisms in
bacterial organisms, other biology
biological organisms in our design of
synthetic solar cells so that they will
change themselves in the way that they
will absorb light when the light is low
and still be efficient and will know how
to protect themselves in high light so
that they're not damaged Bacteria are
able to fix themselves
A typical solar cell may not be able to
fix itself so we have to integrate
within it the same properties which will
be able to turn on and turn off in a
automatic fashion and this is what we
discovered we discovered a molecular
switch which turns itself on and turns
itself off depending on the level of
light
These are kind of things we'd like to
integrate in the future in hybrid
solar cells or even synthetic solar
cells
