Biology subjects

Gomez Ho, S.

Publications and source records attributed to Gomez Ho, S..

2 recordsLinked to original sources

bioRxiv2025

Bacterial exploration of solid/liquid interfaces: developing platforms to control the physico-chemical microenvironment

Bacterial long-term contamination of surfaces is a promiscuous phenomenon often linked to harmful processes. Early bacterial exploration of interfaces, governed by adhesion and individual motility, is a known determinant of the subsequent development and persistence of bacterial colonies. However, the mechanisms by which bacteria integrate various environmental signals at these interfaces and modulate their behavior in response remain poorly understood. Here we present methods for designing precisely controlled microenvironments that enable the manipulation of both physical and chemical properties of solid-liquid interfaces, and also permit in situ monitoring of bacteria at these interfaces within microfluidic flow cells. Our aim is to provide an innovative toolbox for the interdisciplinary research community focused on elucidating the complex processes underlying bacterial surface exploration. We illustrate its use here by examining the surface motility of the pathogen Pseudomonas aeruginosa.

biophysics↗

bioRxiv2022

Substrate stiffness impacts early biofilm formation via a modulation of twitching motility

Surface-associated lifestyles dominate in the bacterial world. Large multicellular assemblies, called biofilms, are essential to the survival of bacteria in harsh environments, and are closely linked to antibiotic resistance in pathogenic strains. Biofilms stem from the surface colonization of a wide variety of substrates encountered by bacteria, from living tissues to inert materials. Here, we demonstrate experimentally that the promiscuous opportunistic pathogen Pseudomonas aeruginosa explores substrates differently based on their rigidity, leading to striking variations in biofilm structure, exopolysaccharides (EPS) distribution, strain mixing during co-colonization and phenotypic expression. Using simple kinetic models, we show that these phenotypes arise through a mechanical interaction between the elasticity of the substrate and the type IV pilus (T4P) machinery, that mediates the surface-based motility called twitching. Together, our findings reveal a new role for substrate softness in the spatial organization of bacteria in complex microenvironments, with far-reaching consequences on efficient biofilm formation.

biophysics↗