Chemical paths

Frequent use and misuse of antimalarials [drugs that fight malaria] can lead to malaria parasites that are resistant to existing treatments. For this reason, there "is an urgent need for new drugs to combat malaria". "Researchers report that they have discovered -- and now know how to exploit -- an unusual chemical reaction mechanism that allows malaria parasites and many disease-causing bacteria to survive."

The same research team from the University of Illinois, led by Eric Oldfield, developed an inhibitor of a pivotal chemical reaction. This inhibitor may fight malaria [and other bacterial and parasitic diseases] in a manner that is different from the traditional medicines. The situation is dire, according to Oldfield. "The parasites that cause malaria also have become resistant to quinine, chloroquine and now, artemisinin, three common treatments for the disease."

"The new study focuses on an essential chemical pathway that occurs in malaria parasites and in most bacteria but not in humans or other animals, making it an ideal drug target." An enzyme, known as IspH, promotes the assembly of a "class of compounds, called isoprenoids, which are essential to life" and prove to be necessary to the bacteria and parasites that cause disease.

"Isoprenoids are the largest class of compounds on the planet," Oldfield said. "There are over 60,000 of them. Cholesterol is an isoprenoid. The orange beta-carotene in carrots is an isoprenoid. And bacterial cell walls are made using isoprenoids." After a decade of research, scientists believe that they understand the structure and function of IspH and hope that it will "allow them to find a way to... shut down production of isoprenoids in the disease-causing bugs," thereby reducing their numbers.

"We're really at the initial, key stage, which is understanding structure and function and getting clues for inhibitors -- drug leads," he said. "But there are a finite number of proteins unique to bacteria and malaria parasites that can be targeted for the development of new drugs. And everyone agrees that this enzyme, IspH, is a tremendous target."

Further research:
Eric Oldfield et al. Bioorganometallic mechanism of action, and inhibition, of IspH. Proceedings of the National Academy of Sciences, Feb 15, 2010. http://www.news.illinois.edu/WebsandThumbs/Oldfield,Eric/0215pnas.200911087.pdf
The National Institute of General Medical Sciences at the National Institutes of Health funded this research.


Source:
University of Illinois at Urbana-Champaign (2010, February 16). New weapon to fight disease-causing bacteria, malaria developed. ScienceDaily. Retrieved February 16, 2010, from http://www.sciencedaily.com¬ /releases/2010/02/100215173944.htm

Photo source:
http://insciences.org/article_album_file.php?article_id=8350&articlemedia_id=1069