How parasites infect their hosts

Together with Scottish colleagues scientists around Prof. Dr. Peter Bayer and Dr. Anja Matena at the University Duisburg-Essen (UDE) have now seen through the oomycetes’ tactics. There results have been published in the prestigious American journal PNAS (Proceedings of the National Academy of Sciences).

Phytophthora infestans, a pathogenic oomycete causing the potato blight, was the origin of the big dearth in Ireland in 1845. To date this organism is still incurring crop damages amounting to millions to the farming industry worldwide. However, oomycetes are not only capable of attacking and infesting plants, but also animals and in rare cases humans. Therefore, oomycetes and their way of spreading have drawn the lively interest of scientists.

In collaboration with colleagues from Aberdeen and Dundee the scientists from the research group „Structural and Medicinal Biochemistry“ have decrypted the mechanism by which oomycetes penetrate cells of their host organisms. Like a Trojan horse they infiltrate a protein into the host cell, thereby weakening the host’s immune system while clearing the way for the parasite. For the first time the scientists could demonstrate the occurrence of chemical modified amino acids (sulpho-tyrosines) on the host’s surface proteins, which serve as molecular anchors for docking and invasion of the parasite.

This discovery turns out to be a far-reaching discovery as those sulpho-tyrosines play key roles in the processes by which HIV and plasmodium, the causative agents of AIDS and malaria, infect their human hosts. The scientists now believe that they got to the bottom of a general and common mechanism that has been developed by different groups of parasites to infect eukaryotic host organisms.

doi: 10.1073/pnas.1113775109 PNAS February 7, 2012 vol. 109 no. 6 2096-2101

More information:
http://www.pnas.org/content/109/6/2096.abstract
Prof. Dr. Peter Bayer, Tel. 0201/183-4677, peter.bayer@uni-due.de