Final Activity Report Summary - BRISENZ (Enzymology of polyketide biosynthesis) The project involved effort from seven Ph.D. students funded via the MC EST project, supervised by seven academics at the University of Bristol. The focus of the project was to further understand the process of polyketide biosynthesis in bacteria and fungi. Polyketides are a class of natural product produced by bacteria fungi and plants and these compounds often possess potent and useful bioactivities - for example lovastatin which is an anticholesterol compound and the pseudomonic acids which are useful antibiotics active against MRSA. The seven projects aimed to deploy a wide variety of methods including synthetic chemistry, analytical chemistry, structure determination of biomolecules by NMR and X-ray crystallography, molecular biology and proteomics. Overall the project has resulted in the successful training of 7 MC EU fellows to Ph.D. level - thus far 5 of the fellows have obtained their Ph.D.s and the remaining two will submit their Ph.D. theses for examination within the next 3 months. The project has resulted in 15 peer reviewed scientific articles in international journals to date, with more submitted and in preparation.Key scientific highlights include:1. First development of a series of kinetic assays for Type II iterative PKS enzymes which allow dissection of the individual catalytic steps;2. First use of the above assays to probe protein protein interactions in Type II PKS;3. NMR observation of acylated Acyl Carrier Proteins and their changes in structure;4. Structure determination of ACP bound to a malonyl transferase enzyme;5. NMR determination of the interaction of a PKS ACP with fatty acyl substrates;6. Determination of catalytic relationships between Fungal and bacterial iterative PKS proteins;7. Understanding of citryl CoA formation using high-level QM/MM methods;8. Understanding of acetyl CoA deprotonation steps by citrate synthase;9. Understanding the contribution of substrate polarisation in citrate synthase;10. Development of heterologous expression systems for fungal PKS genes;11. Understanding oxidative post-PKS reactions in a fungus;12. Use of synthetic chemical intermediates to probe mupirocin biosynthesis.
