Testing of novel AOX inhibitors targeted at the cacao pathogen Monoliophthora perniciosa

Abstract

The cocoa tree provides the raw material for the production of chocolate, which in terms of global demand grows by the year. In spite of its importance, the cocoa farms, located mainly in equatorial regions, suffer great production losses due to the attack of fungal pathogens. Brazil was once a great cocoa exporter, standing as the second largest world producer. However, the onset of the Witches' Broom Disease of cocoa (WBD) in the early 1990s caused the collapse of the Brazilian farms. After almost 30 years, Brazil has still not fully recovered from this scenario. The WBD is caused by the basidiomycete fungus Moniliophthora perniciosa, and, thus far, there is no effective way of controlling this pathogen. However, M. perniciosa's mitochondrial enzyme Alternative Oxidase (MpAOX) has been suggested to be the major factor of virulence and survival, and is now considered to be a relevant molecular target for the development of new fungicides. Dr. Moore's research group (University of Sussex, UK) has a long track record in characterizing the AOX enzyme from a number of organisms, and is currently developing novel AOX inhibitors with antifungal activity. This project aims at characterizing the recombinant MpAOX and assessing the effect of Dr. Moore's inhibitors on this enzyme. This will be useful in the development of new methods to control M. perniciosa, as well as adding further information on the structure of fungal AOXs and their inhibitors.