Published by Communications and Public Affairs (519) 824-4120, Ext. 56982 or 53338
January 13, 1999
Recapturing the glory days for antibiotics
Penicillin and other traditional antibiotics seem to have lost their punch. But could there be a way to recover their former glory?
That's what Anthony Clarke, chair of the University of Guelph's Department of Microbiology and Profs. Gary Dmitrienko and Thammaiah Viswanatha of University of Waterloo's Chemistry Department, hope to discover. Their research, among the first of its kind, focuses on defeating the mechanisms that disease-causing bacteria have evolved to evade beta-lactam antibiotics. Beta-lactam antibiotics include drugs such as penicillin and cephalosporins.
Their strategy is to design target enzyme-activated inhibitors similar in structure to penicillin and the cephalosporins. Beta-lactamases will bind to and cut these inhibitors in the same fashion as for the antibiotics. The cleaved inhibitors will then rearrange to produce an activated compound which will attack the beta-lactamase enzyme and destroy it. The researchers believe this will allow co-administered, intact antibiotics to wipe out the invading bacteria.
"Bacterial resistance to antibiotics is a major problem today in the clinical therapy of infectious diseases," says Clarke, a member of the Canadian Bacterial Diseases Network. "There could soon be no effective antibiotics available to treat some major pathogens."
The culprits are beta-lactamases -- enzymes produced by the bacteria which render these antibiotics ineffective. Beta-lactamases can be easily transferred between bacterial species.There are four classes of beta-lactamases: A, B, C, and D. Successful inhibitors have already been developed for the A, C, and D beta-lactamases. However, the class B beta-lactamases have not yet been conquered and will be the focus of Clarke, Dmitrienko, and Viswanatha's research.
CONTACT: Anthony Clarke, Department of Microbiology, (519) 824-4120 Ext. 3361/4902