Enzyme Behind Meningitis Identified

by Gopalan on Dec 4 2008 12:15 PM

Australian researchers have identified the enzyme that could be behind infections such as meningitis and bactremia.

Stalling the function of the enzyme called oxidoreductase could help prevent microbial infections, it is hoped.

The scientists at the University of Western Australia had sought to know how the bacterial pathogen Neisseria meningitidis causes disease in humans. The microorganism is transferred between people in respiratory droplets and causes rapidly fatal blood poisoning in young children.  Available vaccines are not completely effective and about 400 cases occur in Australia each year.

Dr Charlene Kahler, senior lecturer in the UWA’s School of Biomedical, Biomolecular and Chemical Sciences, said, "Like many microorganisms, the pathogen Neisseria meningitidis synthesises proteins and exports them out of the cell. These exported proteins help the microorganism invade and grow inside the human body.  One of the common features of these proteins is that they are folded and held in the correct conformation by a special bond - the disulfide bond.

"The bond is incorporated into the protein by an enzyme called an oxidoreductase.  Without oxidoreductases, many pathogenic bacteria cannot cause any disease at all.  Although the enzyme is found in most microorganisms, it isn't clear how it recognises the proteins into which it adds the bond.”

In collaboration with Dr Martin Scanlon at Monash University, Kahler was able to crystallize the oxidoreductase and also define its structure. This information should lead to future studies on developing molecules that could successfully frustrate the oxidoreductase enzyme and that way prevent microbial infections.

The findings have been published in the November issue of the prestigious Journal of Biological Chemistry