Characterisation of the antiviral properties and mechanism of action of natural product MM 46115

The influenza A virus is a major cause of severe respiratory infection, which results in 20,000 hospitalisations per year in the UK. Vaccines have been developed against the virus to prevent severe infections, but vaccine hesitancy limits their utility. Antiviral drugs are administered to hospitalised patients to prevent replication of the virus. However, the virus has managed to evolve resistance to these drugs, rendering them ineffective. Therefore, there is a pressing need for new and effective treatments.

Actinomadura pelletieri, a bacterium that causes mycetoma, has been reported to produce MM 46115, a spirotetronate polyketide active against multiple viruses, including influenza A. MM 46115 may have the potential to be developed into a novel treatment that overcomes resistance to currently used antiviral drugs.

Previous work has shown that treating influenza infected cells with MM 46115 can reduce cell death without toxic side effects. While the planar structure of MM 46115 has been determined, its relative and absolute stereochemistry remains to be fully elucidated. This is required to develop a better understanding of its structural similarity to other spirotetronate polyketides and begin illuminating the structure-activity relationship.

This project aims to further investigate the antiviral activity of MM 46115 against influenza A using plaque assays, RT-PCR and immunofluorescence. The stereochemistry of MM 46115 will be elucidated using a combination of predictive sequence analysis of biosynthetic enzymes, 2D NMR spectroscopy, CD spectroscopy, X-ray crystallography, and micro electron diffraction. Proteomics will also be used to identify protein targets for MM 46115. Finally, a better understanding of MM46115 biosynthesis will be developed, enabling bioengineering approaches to the production of structural analogues that inform the structure-activity relationship to be employed.