A variety of bacterial pathogens use nanoscale protein fibers called type IV pili to mediate cell adhesion, a primary step leading infection. Currently, how these nanofibers respond mechanical stimuli and this response is used control adhesion poorly understood. Here, we atomic force microscopy techniques quantify the forces guiding Pseudomonas aeruginosa surfaces. Using chemical single-cell spectroscopy, show that strongly bind hydrophobic surfaces in time-dependent manner, while they...

Single-cell force spectroscopy is a powerful atomic microscopy modality in which single living cell attached to the cantilever quantify forces that drive cell-cell and cell-substrate interactions. Although various single-cell protocols are well established for animal cells, application of method individual bacterial cells remains challenging, mainly owing lack appropriate methods controlled attachment live on cantilevers. We present nondestructive protocol single-bacterial spectroscopy,...

Staphylococcus aureus is an important opportunistic pathogen which a leading cause of biofilm-associated infections on indwelling medical devices. The cell surface-located fibronectin-binding protein A (FnBPA) plays role in the accumulation phase biofilm formation by methicillin-resistant S. (MRSA), but underlying molecular interactions are not yet established. Here, we use single-cell and single-molecule atomic force microscopy to unravel mechanism FnBPA mediates intercellular adhesion. We...

Summary SdrG is a cell surface adhesin from S taphylococcus epidermidis which binds to the blood plasma protein fibrinogen ( Fg ). Ligand binding follows ‘dock, lock and latch’ model involving dynamic conformational changes of that result in greatly stabilized adhesin–ligand complex. To date, force dynamics this multistep interaction are poorly understood. Here we use atomic microscopy AFM ) unravel strength localization at molecular resolution. Single‐cell spectroscopy shows mediates...

ABSTRACT The localization of the LapA protein to cell surface is a key step required by Pseudomonas fluorescens Pf0-1 irreversibly attach and form biofilm. member diverse family predicted bacterial adhesins, although lacking high degree sequence similarity, members do share common domains. Here, using mutational analysis, we determine significance each domain feature in relation its export function biofilm formation. Our previous work showed that N terminus for cleavage periplasmic cysteine...

Despite the clinical importance of bacterial–fungal interactions, their molecular details are poorly understood. A hallmark such medically important interspecies associations is interaction between two nosocomial pathogens Staphylococcus aureus and Candida albicans, which can lead to mixed biofilm-associated infections with enhanced antibiotic resistance. Here, we use single-cell force spectroscopy (SCFS) quantify forces engaged in co-adhesion, focusing on investigated S. epidermidis–C....

Cellular morphogenesis in the fungal pathogen Candida albicans is associated with changes cell wall composition that play important roles biofilm formation and immune responses. Yet, how modulates biophysical properties interactions of surface molecules poorly understood, mainly owing to paucity high-resolution imaging techniques. Here, we use single-molecule atomic force microscopy localize analyze key components living C. cells during morphogenesis. We show yeast-to-hypha transition leads...

Although bacterial pili are known to mediate cell adhesion a variety of substrates, the molecular interactions behind this process poorly understood. We report direct measurement forces guiding pili-mediated adhesion, focusing on medically important probiotic bacterium Lactobacillus rhamnosus GG (LGG). Using non-invasive single-cell force spectroscopy (SCFS), we quantify between individual bacteria and biotic (mucin, intestinal cells) or abiotic (hydrophobic monolayers) surfaces. On...

The large adhesin protein LapA mediates adhesion and biofilm formation by Pseudomonas fluorescens. Although is thought to involve the long multiple repeats of LapA, very little known about molecular mechanism which this attachment. Here we use atomic force microscopy unravel biophysical properties driving LapA-mediated adhesion. Single-cell spectroscopy shows that expression on cell surface via biofilm-inducing conditions (i.e., phosphate-rich medium) or deletion gene encoding LapG protease...

Candida glabrata is an opportunistic human fungal pathogen which binds to surfaces mainly through the Epa family of cell adhesion proteins. While some proteins mediate specific lectin-like interactions with epithelial cells, others promote and biofilm formation on plastic via nonspecific that are not yet elucidated. We report measurement hydrophobic forces engaged in Epa6-mediated by means atomic force microscopy (AFM). Using single-cell spectroscopy, we found C. wild-type (WT) cells attach...

Understanding the mechanisms of interactions between zinc-based layered double hydroxides (LDHs) and bacterial surfaces is great importance to improve efficiency these antibiotic-free antibacterial agents. In fact, role surface in activity LDH nanoparticles compared that dissolution generation reactive oxygen species (ROS) still not well documented. this study, we show ZnAl exhibit a strong effect against Staphylococcus aureus by inducing serious cell wall damages as revealed tests atomic...

ZnAl LDH NPs showed remarkable antifungal properties against C. albicans fungal cells. The activity was linked to the adhesion-specific interactions between nanoparticles and , which were probed by both SPFS SCFS.

Knowledge of the molecular bases underlying interaction fungal pathogens with immune cells is critical to our understanding infections and offers exciting perspectives for controlling responses therapy. Although fluorescence microscopy a valuable tool visualize pathogen-host interactions, spatial resolution low, meaning fine structural details interacting cannot be observed. Here, we demonstrate ability correlated fluorescence-atomic force (AFM) image various steps between macrophages...

We developed a new in vitro model for multi-parameter characterization of the time course interaction Candida fungal cells with J774 murine macrophages and human neutrophils, based on use combined microscopy, fluorometry, flow cytometry viability assays. Using fluorochromes specific to phagocytes yeasts, we could accurately quantify various parameters simultaneously single infection experiment: at individual cell level, measured association phagocyte survival, monitored parallel overall...

The advent of fungal pathogens that are resistant to the classic repertoire antifungal drugs has increased need for new therapeutic agents. A prominent example such a novel compound is caspofungin, known alter cell wall biogenesis by inhibiting β-1,3-D-glucan synthesis. Although much progress been made in understanding mechanism action little about its influence on biophysical properties cells. Here, we use atomic force microscopy (AFM) demonstrate caspofungin induces major remodelling...

Macroscopic assays that are traditionally used to investigate the adhesion behaviour of microbial cells provide averaged information obtained on large populations and do not measure fundamental forces driving single-cell adhesion. Here, we use force spectroscopy (SCFS) quantify specific non-specific engaged in human fungal pathogen Candida albicans. Saccharomyces cerevisiae expressing C. albicans protein Als5p were attached atomic microscope tipless cantilevers using a bioinspired...

We fabricated an electrochemical molecularly imprinted polymer (MIP) chemosensor for rapid identification and quantification of E. coli strain using 2-aminophenyl boronic acid as the functional monomer. This is a modified Gram-negative Escherichia bacterium, ordinary human gut component. The strongly interacts with because porous flexible polymers cell wall. SEM imaging showed that bacteria template was partially entrapped within polymeric matrix in single step. Moreover, this confirmed K-12...

In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion ("flocculation") is conferred by a family of lectin-like proteins known as flocculin (Flo) proteins. Knowledge adhesive and mechanical properties flocculins important for understanding mechanisms adhesion, may help controlling behaviour in biotechnology. We use single-molecule single-cell atomic force microscopy (AFM) to explore nanoscale forces engaged flocculation, focusing on role Flo1 prototype flocculins. Using AFM tips...