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Biology graduate Lee Williams ’03 (Farmington, N.Y.) earned honors Saturday by completing a year-long research project on how bacteria respond to changes in their environment.

Williams graduated cum laude and was elected to Sigma Xi, the national honor society for scientific research. She conducted her research under the direction of Laurie Caslake, assistant professor of biology.

“Dr. Caslake helped me greatly,” she says. “When I ran into problems or got results I didn’t understand, she was great at guiding me to find the answer myself. With her help I learned multiple microbiology techniques and how to apply them.”

Williams presented her research April 4-6 at the 79th Annual Meeting of the Pennsylvania Academy of Science in Grantville, Pa. She was one of 22 Lafayette students to share their research at the conference (see related story).

“My project involved investigating the organic mercury resistance of bacteria in Onondaga Lake in Syracuse, N.Y.,” she says. “I was especially interested in the location, identity, and role of the gene merB.”

Mercury occurs naturally at relatively safe levels, but industrial activities have produced vast quantities of a toxic, “ionic” form of mercury that water-borne bacteria can easily convert into the even more deadly methylmercury. Previous research has shown that plants engineered to contain the bacterial gene merB transform methylmercury to ionic mercury. Another bacterial gene, merA, when inserted into plants, causes plants to convert ionic mercury to elemental mercury that dissipates into the atmosphere. These genes cause plants to produce a protein that acts as a catalyst, converting one form of mercury to another.

“Lee and I came up with the idea for this project together,” says Caslake. “Since she grew up near Lake Onondaga, she had an interest in my research on mercury-resistant bacteria there.”

To analyze why certain organisms are resistant to mercury, Williams conducted challenging experiments using gene sequencing and polymerase chain reaction, which allows a short stretch of DNA to be amplified about a million fold so that one can determine its size, nucleotide sequence, etc.

“In molecular biology precision is key, often leading to multiple repetitions of the same experiment to get it right,” explains Williams. “This leads to the reward of performing an experiment that not only gives you results, but [gives you] the ones you were looking for.”

Caslake notes that presenting at the PAS conference was a great chance for Williams to review her honors thesis before the final oral defense. Williams agrees.

“The conference was a good experience,” she says. “I was nervous about presenting my work, but in the end it went well and was good preparation for the thesis presentation I gave in May for the biology department.

The project may also have helped Williams arrive at some career decisions.

“I decided to do a thesis in order to gain experience in a long-term research project,” she says. “Being a biology major, lab work is one possible future career I have considered. I felt this experience would help me determine if it was right for me or not.”

Working on a thesis and presenting at the PAS Conference are just two of many positive experiences Williams has had at Lafayette.

“Lafayette is a small school which provides an environment where teachers can commit time to doing projects with students,” she says. “Professors are approachable and are willing to help you learn and excel in whatever area of study you may be interested in.”

Categorized in: Academic News