Great wall of fungus comes tumbling down
Dr van der Weerden.
A young biochemist at La Trobe University has demonstrated that a protein from ornamental tobacco is able to break through cell walls and kill a fungal cell that causes major disease and crop losses in plants worldwide.
The discovery, which was published in May in the Journal of Biological Chemistry, will be used by the recentlyfloated biotech company Hexima Ltd in its bid to design transgenic crops that are resistant to fungal attack.
Pathogenic fungi reduce the yield of Australia's cotton crop and in some regions the soil which is infected cannot be used to grow cotton. Hexima Ltd has developed transgenic cotton that has shown promising results in field trials.
Dr Nicole van der Weerden won two prizes for her PhD research on the fungus, a Victorian Fellowship worth $18,000 to travel to laboratories in Vancouver and a fellowship from the International Union of Biochemistry and Molecular Biology to attend a Young Scientists Forum in Greece in July.
'I am interested in research that has commercial applications', Dr van der Weerden says. She has spent three years in the laboratory mapping the way defensin breaks into the cytoplasm of a Fusarium oxysporum cell. This is the fungus that causes a 'wilt' disease of cotton known as Fusarium wilt. By knowing the structure of the defensin molecule in detail, she developed a series of fluorescent tags that can be used to track it's pathway through the cell wall and into the cytoplasm of the fungal cells.
The ornamental tobacco plant from which the protein is derived.
'My research shows that this defensin works differently to others being studied', she says. 'If we can identify the receptors involved we may be able to create better versions of the protein which are more effective at lower concentrations.'
The research could also have application for control of fungal diseases in other crops. Another potential application is for the treatment of human fungal infections such as Candida albicans (thrush) and Aspergillus, as these fungi are becoming resistant to commonly used treatments.
Dr van der Weerden was supervised by Professor Marilyn Anderson, co-founder of Hexima Ltd with Professor Adrienne Clarke and Dr Robyn Heath at the University of Melbourne.