Isolation and characterization of novel microbial natural products that activate autophagy

Autophagy, which means ‘self-eating’, is an essential process that involves the degradation of cytoplasmic material. Cells use autophagy to generate materials and energy when conditions become unfavourable. They also use this process to clear damaged cellular components or specific proteins in order to abolish their function when it is not needed in the cell. Dysfunction in autophagy has been implicated in most of the diseases, like cancer, neurodegeneration, bacterial and viral infections. Autophagic activity in our cells declines when we get older, and this has been associated with the development of diseases (1) . Therefore, it would be very important to find interventions to activate autophagy and keep its levels high through the life course. To address this, we will use natural products from Streptomyces bacteria. These micro-organisms have already provided human kind with many metabolites with therapeutic interest. Rapamycin is a Streptomyces natural product already known to induce autophagy. However, rapamycin has negative side effects like immunosuppression. Thus, there is a need to identify more natural compounds that can be produced in large quantities and have no side effects. A series of structural analogs of rapamycin as well as structurally diverse natural products will be isolated from Streptomyces culture extracts and their activity investigated. The aim of this project is to isolate and characterize novel natural compounds that can activate autophagy. Specifically, we will: 1) Isolate known and novel natural compounds from diverse culture extracts prepared using Streptomyces species; this will involve a range of analytical chemistry techniques (i.e. LC-MS for identification, HPLC for purification and NMR spectroscopy for structural elucidation) and will be supported with bioinformatics investigations to predict the nature of the compounds of interest. 2) We will test if these compounds activate autophagy in vitro in mammalian cells and in vivo in Drosophila larva and adult flies and Drosophila models of human neurodegenerative diseases 3) Compounds that have strong pro-autophagic activity will be selected and the molecular and cellular pathways of activation of autophagy will be characterized.

References:

He C, Klionsky DJ (2009) Regulation mechanisms and signaling pathways of autophagy. Annu Rev Genet. 43:67-93.

BBSRC Strategic Research Priority: Understanding the rules of life – Neuroscience and Behaviour, and Microbiology, and Integrated Understanding of Health - Pharmaceuticals, and Ageing.

Techniques that will be undertaken during the project:

Basic cell, molecular biology and biochemistry: (western blotting, molecular cloning, immunocytochemistry):

Drosophila genetics and cell biology

Confocal microscopy

Molecular microbiology

Analytical chemistry: chromatography techniques, mass spectrometry and NMR spectroscopy

Bioinformatics