Researchers in the laboratory of Amy Anderson, Assistant Professor of Chemistry, have unveiled the structure of an enzyme called dihydrofolate reductase-thymidylate synthase, also known as DHFR-TS, from a waterborne parasite called Cryptosporidium hominis. Knowing the chemical structure of the enzyme will help researchers design highly targeted drugs to combat the parasite, which needs this enzyme to reproduce.

"We wanted to know how DHFR-TS is assembled and how it works," says Anderson. "Then we'll know how to disable it and kill the parasite."

Anderson, along with Robert O'Neil, a senior researcher and the lead author of the study, Ryan Lilien, an M.D./Ph.D. graduate student at Dartmouth, Bruce Donald, Professor of Computer Science, and Robert Stroud, Biochemistry and Biophysics Professor at Univ. of Calif. at San Francisco, have solved the puzzle of DHFR-TS by revealing its chemical architecture.

Their results were electronically published on October 9 in an online issue of the Journal of Biological Chemistry, and the paper appeared in the print edition of the journal on December 26, 2003. The study was also rated as "exceptional" and a "hidden jewel in microbiology" by the Faculty of 1000, a group of researchers who rate published articles in the life sciences each month.

The Centers for Disease Control and Prevention (CDC) have been watching Cryptosporidium and tracking its impact on human populations, where it spreads easily and quickly, for more than 20 years. While healthy people stricken with this parasite usually recover on their own, it can be deadly for children, elderly people and those whose immune systems are compromised, like people with HIV/AIDS or patients undergoing chemotherapy. According to the CDC Web site, Cryptosporidium is often found in public water su
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Contact: Sue Knapp
Sue.Knapp@dartmouth.edu
603-464-3661
Dartmouth College
5-Jan-2004