Nanomechanical intervention of bacterial mechanotransduction

Mechanical force is a ubiquitous perturbation that operates at all levels of life, from single molecules to organs.

At the tissue level, cells are constantly exposed to forces exerted by their surrounding environment—body fluids, neighboring cells, or the extracellular matrix.

The process by which cells sense and convert physical stimuli into a biochemical signal is known as mechanotransduction.

When mechanical forces reach the nucleus, they can activate several force-induced transcriptional pathways that control cell functionality. The failure of these pathways has been linked to several human pathologies, such as cancer.

While most of our knowledge in mechanobiology is focused on mammalian cells, comparatively little is known on how prokaryotes detect, interpret, and generate a response to physical inputs.

Understanding how bacteria sense mechanical forces and how these signals are integrated to promote colonization, biofilm formation, or virulence development is crucial to develop therapeutic strategies that target the pathogenesis onset.

Here we propose a cross-scale approach that first employs single-molecule force spectroscopy techniques to study in vitro the dynamics under force of PilY1 —from the Gram-negative opportunistic pathogen Pseudomonas aeruginosa— and how antibody binding affects its mechanical stability.

Our goal is to implement a molecular-based strategy that disrupts the PilY-triggered mechanotransduction pathway, which we will probe at the cellular level.

Using a combination of optical microscopy and single-cell mechanical techniques, we will monitor in vivo the downstream events that lead to the expression of genes that promote virulence after PilY1 mechanical stimulation in the absence and presence of antibodies that disrupt the activity of this protein.