Project description
Super-resolution microscopy to study subcellular properties of bacterial cells and mitochondria
Eukaryotic cells are tens of microns in size and contain organelles including mitochondria, which originated from ancient bacterial endosymbionts. The goal of the EU-funded Piko project is to elucidate the organisation and dynamics of the bacterial cytoplasm and the mitochondrial matrix. A known obstacle in the study of the interior of bacteria and mitochondria is the relevant length scales, which are below the diffraction limit. Researchers aim to overcome these technical challenges using high-throughput super-resolution fluorescence microscopy. The new microscopes can capture thousands of cells in each experiment at super-resolution, allowing dynamic structural and long-term molecular tracking. Ultimately, this will enable the quantitative study of the subcellular properties of single bacterial cells and mitochondria.
Objective
Bacteria cells appear to be less complex than our own cells -- yet they are better able to survive harsh conditions. Typically ~1 micron in size, they lack motor proteins; thus, they rely on fluctuations for intracellular transport. Bacteria in the environment often face starvation and exist in a non-proliferating quiescent state, which promotes antibiotic resistance and virulence. Entering quiescence, the bacterial cytoplasm displays signatures of the colloidal glass transition, with increasingly slow and heterogeneous diffusion. Also important for fitness during starvation is the formation of storage granules up to hundreds of nanometers in size. The complex state behavior of the bacterial cytoplasm is therefore important for their survival, but the physical nature of each of these processes is poorly understood. Our own cells are typically tens of microns in size and contain organelles including mitochondria, which originated from ancient bacterial endosymbionts. But little is known about the transport properties of the mitochondrial matrix, or how it responds to changes in mitochondrial membrane potential or energy production.
The goal of this project is to elucidate the organization and dynamics of the bacterial cytoplasm and the mitochondrial matrix. A major obstacle to studying the interior of bacteria and mitochondria is the relevant length scales, which lie below the diffraction limit. Furthermore, to observe and quantify their adaptive response, many cells must be measured. Our strategy to overcome both of these technical challenges is to use high-throughput super-resolution fluorescence microscopy. We have developed new microscopes, capable of capturing thousands of super-resolved cells in each experiment. We propose to translate these developments to dynamic structured illumination and long-term molecular tracking. Broadly applicable, this will also enable the quantitative study of the subcellular properties of single bacteria cells or mitochondria.
Fields of science
- natural sciencesbiological sciencesmicrobiologybacteriology
- natural sciencesphysical sciencesopticsmicroscopysuper resolution microscopy
- natural sciencesbiological sciencesbiochemistrybiomoleculesproteins
- engineering and technologymaterials engineering
- medical and health sciencesbasic medicinepharmacology and pharmacydrug resistanceantibiotic resistance
Keywords
Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
1015 Lausanne
Switzerland