May 14, 2009
University of Wyoming Professor Randy Lewis lets a tarantula crawl on his shoulder
while research scientist Michael Hinman watches. Although Lewis and Hinman went to
Powell High School at about the same time and were inspired by the same science teacher,
it was not until years later they met in the UW College of Agriculture's Department
of Molecular Biology. (Josie Lorimer Photo)
By Josie Lorimer, UW Journalism Senior
The science bug bit Randy Lewis as he carried out chemistry experiments while attending
Powell High School (PHS) in the late 1960s.
A couple years later, the same bug bit another PHS student, Michael Hinman.
The two wouldn't meet for nearly 15 years, but the story of how one PHS science teacher
influenced both of their lives, the story of how they ended up in the same University
of Wyoming laboratory and the story of their internationally known spider silk research
prove equally fascinating.
Lewis, who graduated from PHS in 1968, is a professor in the UW College of Agriculture's
Department of Molecular Biology, where he and his team of scientists and graduate
students are researching spider silk proteins in hopes of producing a superior fiber
that could one day be used to make artificial ligaments and tendons, improved sutures
for eye surgery and nerve repair and bulletproof vests having the potential of being
stronger yet lighter than ones made of Kevlar.
Prior to focusing on spider silk proteins, Lewis concentrated his UW research on protein
hormones an area of science that fascinated a young University of Oregon Ph.D. chemistry
student by the name of Michael Hinman.
Hinman who graduated from PHS three years after Lewis learned about the Lewis studies
at UW while attending Oregon. Shortly after earning his doctorate in 1984, he sent
a job application to Lewis and was hired.
That's when the two learned they not only shared the same scientific interests but
had both graduated from PHS and had both been heavily influenced by the same high
school chemistry teacher, the late Louis Kohnke.
Kohnke taught at PHS from 1935 until 1976, and Lewis and Hinman were teacher's assistants
(TAs) in his chemistry laboratory.
Lewis said Kohnke allowed students to get involved in experiments and "play in the
chemistry lab." He added the class was fun because Kohnke, though offering guidance
and answering questions, "let you do what you wanted to."
Lewis said Kohnke was a major factor in his decision to study chemistry at the California
Institute of Technology in Pasadena, where he obtained a bachelor's degree in 1972.
He then earned master's and doctorate degrees in biochemistry from the University
of California, San Diego.
Hinman said he was equally influenced by Kohnke. "As TAs, we were encouraged to do
scientific projects. We had all kinds of fun in there."
Shortly after Hinman joined the Lewis lab, Lewis became interested in spider silk
research while consulting with a biotechnology company in San Diego.
The research started by removing spider glands to develop a library of genes, Lewis
said. His team then found the progression of genes and the possible makeup of proteins.
Information was gathered on the genes desired for different properties.
Hinman said different silks can be genetically engineered to get different properties
like strength and elasticity for the cloned protein. Spiders can produce up to six
kinds of silk with very different mechanical properties. These silks can range from
strengths greater than Kevlar to elasticity greater than nylon.
The Lewis lab has now cloned and sequenced genes for the proteins comprising all six
of these silks.
The current research is focused in three areas, Lewis said.
The first is to continue studying the proteins for the last silk as well as the glue
used in the web.
Second, the team is creating synthetic genes expected to both imitate and have properties
different from the natural silks.
Third, these silk proteins are being produced in bacteria and other systems. For example,
proteins are grown in alfalfa, and they are also separated from the fats in goats'
milk.
The proteins are spun and stretched into fibers that are hoped to be stronger, lighter
and more elastic than today's fibers.
There are many people awaiting research results of the Lewis laboratory. Among them
is Evelyn Lewis of Powell, the mother of Professor Lewis. "I think the research will
be wonderful when it works out," she said.
Lewis hopes the research leads to improved materials in three areas.
Medically, the fibers could be used to make artificial ligaments and tendons, which
are now only available from cadavers. The silk could also be used for sutures, making
finer eye surgery and nerve repair possible. The fibers could also be used for tissue
regeneration in bones and some ligaments so the area is not completely immobile while
repaired.
The fibers could also be used to make body armor including protective vests for peace
officers, soldiers and others stronger yet lighter. These fibers could cut the weight
of protective clothing in half, maybe even by two-thirds, Lewis said.
Noting spider silk is more elastic than nylon, Lewis said the research could produce
fibers for parachute cords that would absorb energy to prevent collapsing and stabilize
parachutes.
There could be other applications, too. For example, airbags made with these fibers
would work like a spider web, absorbing energy instead of blasting drivers and passengers
back into their seats. This would also make it safer for children to ride in the front,
Lewis said.
"Although it has taken a large amount of research to reach the point we are at now,
I am very optimistic that products based on spider silk proteins will be on the market
in a couple of years," Lewis said.
Editor's note: Josie Lorimer of Afton, a senior majoring in journalism at the University
of Wyoming, is the primary author of the story. Robert Waggener is an editor in the
UW Cooperative Extension Service and College of Agriculture.
Posted on Thursday, May 14, 2009
