FCS-BACSUB · Unravelling lipid dynamics in bacteria
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2021-09-01 → 2023-08-31
- EU contribution
- €184,708
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Unravelling lipid dynamics in bacteria
Bacteria are fascinating organisms. They are one of the simplest forms of life on earth, yet they can perform multiple tasks (consuming nutrients, moving, dividing…). Fundamental research about bacteria has in the past proved very useful as it allowed the discovery of techniques like PCR or gene editing with CRISPR/Cas9, which readily have life-saving applications. A second reason to study bacteria is to fight antibiotic resistance. Some bacteria are pathogenic: they cause potentially deadly diseases, to both humans and animals. Many of these diseases can easily be treated (cholera, plague, tuberculosis) thanks to fabulous molecules called antibiotics. Unfortunately, some bacteria have developed a resistance to antibiotics and are now much harder to treat. To develop new strategies to kill such bacteria, we need to further our understanding of how exactly these organisms work. With a perfect understanding of how a bacterium works, we can develop strategies to kill them without hurting the human it infected. In this work, we were interested in understanding the physics of the plasma membrane (the envelope that separates the bacterium from its environment). The plasma membrane is a key component of the cell and is the target of many classes of antibiotics. The plasma membrane of every cell, including of bacteria, is a fluid: it is made of molecules moving and important molecules inside the membrane (proteins) can move to perform their role. The viscosity of the membrane is the parameter that governs how fast a given molecule can move within this membrane. It is a parameter of crucial importance, as we know that bacteria change their membrane composition to maintain a certain level of viscosity in response to changes from their environment (typically temperature). The main goal of this project was to develop an instrument capable of measuring this viscosity. Before, scientists could only guess changes in fluidity from changes in composition. Here, we wanted our technique to give us an exact value for the viscosity of the membrane. The second goal of this project was to use this technique to study how the membrane of the bacterium Bacillus subtilis reacts to a change in temperature. This was studied before with different techniques, and we wanted to compare the results we obtained with our new, more precise technique, with the results obtained previously.
Data: CORDIS, © European Union
Project objective
Bacteria are fascinating organism, relatively and yet not fully understood. Fundamental research on bacteria led across the years to major technological breakthroughs like the discovery of genetic editing with CRISPR-Cas9. Besides, resistance of bacteria to antibiotics is becoming a growing public health concern, raising the need for a better understanding of the molecular mechanisms involved. We propose here to further our understanding of the molecular biology of bacteria by studying the dynamic of lipids in bacterial (B. Subtilis) membranes. In eukaryotic cells, it was found that lipid dynamics can reveal the micro- and nanoscale organisation of the plasma membrane, revealing a dynamic interplay between membrane components such as lipids, membrane proteins, and the actin cytoskeleton. Bacterial membranes were thought until recently to be much simpler, but accumulating evidence over the last ten years suggested that they too were highly heterogeneous and dynamic. However, very few studies so far focused on the question of lipid dynamics, in part because of the experimental complexity of such measurements. To address this, we will transfer new technologies based on fluorescence correlation spectroscopy (FCS), that were developed mainly for eukaryotic research, to the field of microbiology. With this unique methodology, we will answer a series of fundamental open questions: how do bacterial membranes organise at the nanoscale? Do they exhibit transient lipid-mediated interactions (called lipid rafts) as is thought to be the case in eukaryotes? Does MreB, bacterial equivalent of actin, also compartmentalises lipid diffusion? Answering these questions will help us build a holistic picture of the mechanisms associated with essential bacterial processes such as biofilm formation or antibiotic resistance, which will have far-reaching implications in both biology and medicine.
Original text from CORDIS.
Participants
- INSTITUT NATIONAL DE RECHERCHE POUR L'AGRICULTURE, L'ALIMENTATION ET L'ENVIRONNEMENT · ParisCoordinatorFrance
Links
Data: CORDIS, © European Union