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my friends and i were just talking about if there would ever be a cure for certain things. thats when they told me about an arcticle they had read in a magazine recently about dna research using alligator dna. i will post the arcticle here-
"There is a battle raging, a life-and-death struggle against an
adaptive, elusive, unrelenting enemy. It’s not the war on
terror. It is man against microbe in a world war where
opportunistic invaders have been aided and abetted by careless
overuse of antibiotics and one-time wonder drugs that have lost
their potency against pathogens. It is a war against time.
Today, science is desperately searching for new immunological
approaches both in high-tech laboratories and exotic
locales. New answers are sought in virgin rainforest and deep
ocean swells, but it could be that the next big “secret weapon”
in this war is lurking in the bayous of Southeast Texas and
Louisiana.
Alligators might make most people think of life-threatening
injuries, but to biochemist Mark Merchant ’88, they could
yield new ways of healing. Merchant has found that alligators—
and their immune systems—could someday help us in our fight
against infection.
The grandson of a Cajun rice farmer, Merchant grew up
hunting and fishing along the Louisiana and Southeast Texas
coasts, and he has seen plenty of alligators. Now an associate
professor of biochemistry at McNeese State University in Lake
Charles, La., he has great admiration—and healthy respect—for
these fiercely territorial reptiles.
“They fight,” Merchant said. “They tear limbs off each
other, and it’s very common for us to catch alligators that are
missing limbs. Despite the fact that they live in this environment
with all these microbes, they heal very rapidly and almost
always without infection.”
Virtually unchanged for more than 175 million years, the
reptiles’ aggressive lifestyle puts a selective pressure on them.
“You adapt, or you die. You either have to back off your
lifestyle, or you adapt by developing some kind of immune system
to fight the bacteria that you live around, because if you’re
going to have a lot of these terrible wounds and be exposed to
all the bacteria in the area, you’re going to need to have very
good defense mechanisms.”
“We think that part of that defense mechanism will be able
to help us as humans and that modern molecular medicine
should be able to benefit,” Merchant said.
Powerful infection-fighting proteins—short chains of
amino acids known as antibiotic peptides—could help fight
against antibiotic-resistant bacteria. Active proteins extracted
from alligators’ white blood cells have been found to kill a variety
of bacteria and fungi. Merchant has shown that peptides can
kill the herpes simplex virus, as well as fungal diseases and a
broad range of bacteria, including MRSA (methicillin-resistant
staphylococcus aureus) the lethal “super bug” that is becoming
increasingly resistant to current antibiotics. He presented his
findings at the annual meeting of the American Chemical
Society.
“We’re taking advantage of millions of years of Mother
Nature’s product development. We do need a new class of
drugs. That’s what is exciting—this wouldn’t just be a new drug
but potentially a new class of drugs that work by a completely
new class of mechanisms,” Merchant said. It may be difficult to
meet the challenges of adapting peptides for clinical use, but,
despite this, antibiotics containing alligator-blood-derived
proteins could be on our shelves in 10 years, Merchant said.
Interest in immunology
Researching alligators wasn’t Merchant’s focus, just one of
several areas of interest when he first came to McNeese. But
after fruitless Internet searching on the topic of alligators and
infection, he soon realized that he had found an opportunity. “I
kept thinking I wasn’t putting in the right research terms, but it
became apparent that no one ever broached this issue.”
“They always say in research that all the good ideas have
already been taken,” Merchant said. “That’s not necessarily true.
I landed on a gold mine. We started collecting publication-quality
data from day one.”
Today, Merchant’s discoveries have drawn an unprecedented
international spotlight to the university and have resulted in
scores of published papers, dozens of presentations and lots of
media attention as well. As the knowledge base grows,
Merchant’s research may yield “antibiotics that you take orally,
but potentially also antibiotics that you could use topically on
wounds, such as diabetic ulcer wounds,
burns and things like that. Be it topical or
internal, we hope that we can isolate some
protein that has antibiotic activity that
would avert infection to give time to heal.”
Merchant graduated from Nederland
High School in 1984 and entered Lamar
University pursuing a double major in biology
and chemistry. He still lives in
Nederland, where his wife, Jennifer (Cabra)
’88, who graduated Lamar with a degree in
interior design, now teaches special-needs
children in the Nederland and Port Neches
school districts. The couple has a son, 17,
and two daughters, 15 and 6.
“When I started my senior year at
Lamar, I didn’t have any aspirations of getting
a Ph.D. That was an 11th-hour decision
for me after prodding by some Lamar
faculty who had encouraged me because I
had shown a propensity for research.”
Merchant enjoys keeping up with his
LU professors—now colleagues in academe—
and has high praise for them, but
especially for the late Hugh Akers, who
sparked his interest in biochemistry.
“I worked in his lab as an undergraduate,”
Merchant said. “I was going to go get
a job at one of the plants, but Dr. Akers
said, ‘Hey, you’ve really taken a shine to the
research. Have you thought about going to
grad school? Have you thought about going
to med school? At least consider that.’”
“And so I did. I couldn’t believe I was
applying; I wasn’t ready for four more years
of school. But it was the best decision I’ve
ever made,” Merchant said.
He attended graduate school at Texas
A&M, graduating in 1992, and then spent
three and a half years as a post-doctoral fellow
at University of Texas Medical Branch
in Galveston. “I sometimes joke that I’ve
got a 100-mile rope around my neck,”
Merchant said.
At UTMB, Merchant studied heavymetal-
induced stress genes. “My first loves
are molecular biology, genetic engineering
and gene expression. We were looking at the
molecular biochemical mechanisms of how
genes are turned on and off inside our cells.”
Merchant then came to Beaumont as a
research and development lab manager for
Helena Laboratories from 1996 to 2001
before the lure of research and teaching drew
him to McNeese. There, he is passionate
about his dual role, finding it so enjoyable he
doesn’t consider it work. “I get to go into
the lab and teach and do alligator research.
That’s not work. I can teach students 10
times more in the lab than I can in the classroom,”
Merchant said. “You can really see
the light bulbs come on in the lab. That
excites me to no end.” Eight undergraduates
and two graduate students work with alligator-
related projects in Merchant’s lab.
“For several years, we looked at innate
immunity and acquired immunity,”
Merchant said. “Innate immunity is the
branch of the immune system that does not
require previous exposure. It is the first line
of defense, always in a semi-active state
ready to go to work. It is less specific in its
target but more quick acting, designed to
hold an infection at bay to allow acquired
immunity opportunity to gear up.”
Much of Merchant’s research is on
blood drawn from populations, not from
individual animals, typically pooling blood
from 10 or 15 samples and taking averages.
They have also looked for variations within a
population, Merchant said. While a captive
population of alligators is readily available
across town, most collection from the wild is
done in the summer or during winter breaks.
One current study focuses on phospholipase
A2, an enzyme providing innate
immunity in alligators that is also present in
humans. Interestingly, the enzyme isn’t
found in newly hatched alligators, but, by
one year of age, it is a part of their repertoire
of resistance. Merchant, with his
undergraduate and graduate assistants, is
studying the development of the serumcomplement
system using three groups of
hatchlings under differing conditions. Thus
far, they’ve found that slower-growing, outdoor-
kept hatchlings develop the enzyme
much faster, while their heat-lamp-hogging
counterparts grow up to six times faster, but
develop the immunity much later. A third
group in the latest round of experiments has
the addition of ultraviolet light. The results
are pending.
Merchant’s research interests are finding
funding from a variety of sources,
including the university and the National
Science Foundation. A National Institutes
of Health grant, with a co-investigator at
LSU, is pending.
In 2002, Merchant was introduced to
the Crocodile Specialists Group, a worldwide
research consortium concerned with
crocodilian conservation, preservation, management
and research. Since that time, he
has been a frequent presenter at meetings
around the world and has linked with colleagues
in the U.S., Australia, France and
Bolivia, setting up collaborative research
with croc-expert Adam Britton of Big
Gecko, a wildlife consultancy in Darwin,
Australia, and caiman-experts Luciano
Verdade and Pablo Siroski in Brazil and
Argentina, respectively. In doing research in
comparative biochemistry, Merchant is finding
more similarities than differences
between the species. In just three years, he
has made presentations in 11 countries on
four continents. Merchant enjoys sharing
findings with “people who really care about
this stuff, and that has opened up all these
collaborations and sources of funding outside
the country.”
“You have a stark contrast in new modern
molecular medicines and these ancient
reptiles, a pretty interesting contrast,”
Merchant said as he held a handful of
squirming alligator hatchlings. “They may
have something to offer us. Who knows?”
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