Postdoctoral position in cellular biology / biophysics (M/F)

Job Description

Missions

The group “Methodological developments in AFM for biological applications” at the CBMN (Bordeaux) is currently seeking a postdoctoral researcher specialized in structural, mechanical, dynamical and functional characterization of cells interacting with bacterial peptide assemblies. This is a highly interdisciplinary project, funded by an ERC StG, at the frontier between cellular and structural biology, and biophysics, notably combining atomic force microscopy (AFM) and advanced fluorescence and confocal microscopy.
Project Background. Staphylococcus aureus, an opportunistic pathogen resistant to many antibiotics, relies on a broad arsenal of virulence factors to colonize the host and cause infection. Among them, phenol-soluble modulins (PSMs) are a family of amphiphilic peptides that play a key role in (i) biofilm structuring and maturation, (ii) host cell lysis through membrane disruption, and
(iii) activation of the inflammatory response via specific membrane receptors. Beyond their biological functions, PSMs exhibit a strong propensity to self-assemble into amyloid fibrils with diverse architectures, potentially linked to their cytotoxic and/or pro-inflammatory activities. However, the molecular mechanisms underlying PSM functions remain largely poorly understood.
Project Objective. We aim to understand how the physicochemical properties and self-assembly dynamics of PSMs govern their interactions with cellular membranes — both at the lipid and receptor levels — and ultimately control host cell death and inflammatory response via the G protein-coupled receptor FPR2. To address this question, the project will adopt an in cellulo and multi-scale approach, ranging from live-cell studies to single-molecule analysis, in order to identify the structural, physicochemical, and dynamic determinants involved. The research will be structured around two complementary methodological axes:
1. Link between peptide–membrane interactions and cytotoxicity
Combining viability assays, fluorescence microscopy (confocal, TIRF), and atomic force microscopy (AFM) under physiological conditions, we aim to monitor in real time the morphological and mechanical alterations induced by different PSM assemblies.
2. Quantitative study of PSM–FPR2 interactions
Based on cellular engineering (transient receptor expression), and the reconstitution of complex membranes (proteoliposomes, supported lipid bilayers), we aim to analyse the recognition mechanism involved in immune activation. Single-molecule force spectroscopy experiments (AFM) will be coupled with the investigation of activated signaling pathways using bioluminescence resonance energy transfer (BRET) and fluorescence resonance energy transfer (FRET) approaches.


This project integrates expertise in membrane biophysics, cell biology, and advanced imaging, spanning from the cellular to the molecular scale. It is intentionally flexible: depending on the candidate's expertise and interests, it may focus more specifically on peptide–lipid interactions, receptor recognition mechanisms, or the development of advanced biophysical approaches, thereby offering substantial scientific freedom and strong potential for impact.

Activity

• Cell culture (eukaryotic cells, bacteria)
• Biophysics of peptides and membrane proteins
• Fluorescence microscopies: confocal, TIRF
• Force spectroscopy - Atomic Force Microscopy
• Data analysis and presentation

Your Profil

Skills

We invite applications from innovative and motivated candidates with background in experimental biophysics or cellular biology, or closely related fields, who are intrigued by exploring and coupling cutting-edge methods to unravel the so far enigmatic structure-function relationship of bacterial functional amyloids. We are looking for someone proactive, independent, with good organizational and communication skills, and ability to work in a team environment. The candidate must have :
• Strong knowledge in cellular biology
• Experience with lipids and/or G protein-coupled receptors
• Expertise in confocal microscopy; TIRF expertise will be appreciated.
• Expertise in atomic force microscopy
• Knowledge of biophysical techniques applied to peptides/proteins
• Handling of chemical and biological materials

Your Work Environment

The project is intentionally flexible: depending on the candidate's expertise and interests, it may focus more specifically on peptide–lipid interactions, receptor recognition mechanisms, or the development of advanced biophysical approaches, thereby offering substantial scientific freedom and strong potential for impact.

The project will be supervised by Marion Mathelié-Guinlet at the Institute of Chemistry and Biology of Membranes and Nano-Objects (CBMN), University of Bordeaux, within the framework of her ERC Starting Grant PUMBA. This funding will support the project environment and the potential extension of the postdoctoral contract. In this context, the postdoc will have access to state-of-the-art facilities at the CBMN for structural and nanomechanical investigation of biological systems and correlative imaging. Besides, CBMN provides a perfect, dynamic and stimulating environment for this project, as we significantly collaborate with different teams, experts in cellular / molecular biology, physical-chemistry, and front-end methodological developments to address major challenges in the field of peptide-membrane interactions.

Compensation and benefits

Compensation

Between 3 041€ and 3 467€ monthly gross according to experience

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

The research professions