Discovery of Defence Mechanism Against Oxygen Radicals
NEW treatments for a range of conditions including Alzheimer’s and certain cancers could be developed following research from the University of Bern, Switzerland in collaboration with the University of Stockholm, Sweden. The team discovered that the enzyme called superoxide oxidase acts as a defence mechanism against oxygen radicals, which are believed to play a role in a number of diseases.
Oxygen radicals can be created when oxygen is transformed into water in the cell, which takes place when nutrients such as fats are burned by the body to gain energy. When they are in large quantities, the radicals attack DNA, proteins, and fats, and are therefore believed to contribute to neurodegenerative diseases such as Alzheimer’s, as well as some forms of cancer. While all cells contain special enzymes that defend against these radicals, they become less effective over time.
In this new study, the team identified a previously unknown defence mechanism, which more directly detoxifies oxygen radicals than the other mechanisms that are known. They found that the superoxide oxidase enzyme is able to transform oxygen radicals directly back to a harmless oxygen. It additionally passes an extra electron to the coenzyme Q molecule, which plays a vital role in the manufacturing of biological energy. Therefore, superoxide oxidase not only diffuses oxygen radicals, but also ensures the energy is utilised by the body.
The discovery paves the way for further research on the enzyme to better understand the mechanism of this defence system, which could hopefully lead to the development of new treatments. “On one hand, the enzyme could be optimised in such a way that it can be used as an indicator for superoxide in the laboratory and in medicine; on the other hand, we could some day use inhibitors of the enzyme as a replacement for antibiotics,” added Prof Christoph von Ballmoos, University of Bern.
The next stage is to find out whether a similar reaction occurs in human cells, as the findings of this study were made in the bacterium Escherichia coli.
James Coker, Reporter