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Natalia Oleg Glebova
"Thioredoxin in Bioremediation"
Sponsor: Terrance Leighton, Professor of Biochemistry and Molecular Biology

• Project Description
• Scholar's Photo
• Scholar's Journal

Natalia's Senior Honors Thesis in Biochemistry and Molecular Biology evolves out of her passionate commitment to contribute to the restoration of the environment, a matter she believes should be a priority for modern society. She will be investigating the molecular mechanisms of selenite detoxification in the bacterium Bacillus subtilis, focusing on the function of the proteins thioredoxin and thioredoxin reductase in toxic metal biotransformation. The results of her research will lead to improved bioremediation of selenite-contaminated soil and water and, more broadly, to a better understanding of the practical use of bacteria in bioremediation of environments contaminated by toxic metals.

When I first applied to the Haas Scholars Program, I set out to test my hypothesis that thioredoxin is involved in selenite detoxification in Bacillus subtilis. In order to accomplish this goal, I designed a detailed experimental plan to delete the gene coding for thioredoxin, trxA. I was very excited when I learned in late March that I had received funding for the project.

Unfortunately, just as I was ordering primers and setting out to start the work, a paper was published in April of 1998 that stated that thioredoxin is essential in B. subtilis. My friend Anatoly, another undergraduate researcher, came into the lab one day and told me. We both understood that this discovery meant that the assumption I made when designing my research strategy was wrong. In short, my project plan was obsolete; I could no longer inactivate the gene since the bacteria could not survive without a working gene for thioredoxin.

With a heavy heart, I admitted that my (at the time logical) argument in my Haas research proposal against the possibility of thioredoxin being essential was just wishful thinking. After a few discouraging days of contemplating the usefulness of having written (and presented) a detailed research plan whose major premise was false, I started to look for an alternative approach to the problem. This process involved mostly thinking, consulting my research mentor, thinking, reading the relevant literature, and thinking some more. In the end, I came up with an indirect way of approaching my project, which entails investigating the regulation of thioredoxin under selenite stress. Although my initial plan was no longer valid, by not letting a failure become overwhelming, I was able to circumvent the problems I encountered.