Yves F Dufrêne

..Here I highlight the advances made by my team in this area during the past 3 years...

..In addition, recent developments in cantilever nanosensors have opened up new avenues for the label-free detection of microorganisms and bioanalytes...

..We also discuss recording conditions and data interpretation, and provide recommendations for reliable experiments. For well-trained AFM users, the entire protocol can be completed in 2-3 d...

..specific molecules, can be used to answer pertinent questions related to surface-associated proteins, such as what is their spatial arrangement on the cell surface, and what are the forces driving their interaction with the environment?..

..A new study provides fascinating insights into the sophisticated mechanism by which an ATP-fueled proteolytic machine generates mechanical forces to unfold and translocate multidomain substrates...

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..These noninvasive nanoscale analyses provide new avenues in pathogenesis research, particularly for investigating the action mode of antimicrobial drugs, and for elucidating the molecular basis of pathogen-host interactions...

..This single-molecule study provides novel insight into the architecture of mycobacterial cell walls and offers promising perspectives for understanding the action modes of antimycobacterial drugs...

..Applicable to a wide variety of cells, this single molecule method offers exciting prospects for analyzing the heterogeneity and diversity of macromolecules constituting cell membranes and cell walls...

..Together with the fact that HBHA mediates bacterial aggregation, these observations suggest that the single homophilic HBHA interactions measured here reflect the formation of multimers that may promote mycobacterial aggregation...

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..Even though the presented protocol is for L. rhamnosus, it can be easily modified for other cell types. For users having expertise in the field, the entire protocol can be completed in about 5 d...

..Taken together, these structural, chemical, and immunological data provide novel insight into the action mode of antimycobacterial drugs, as well as into the spatial organization of the mycobacterial cell wall...

..Then, we measured hydrophobic forces associated with mycolic acids on the surface of mycobacteria, supporting the notion that these hydrophobic compounds represent an important permeation barrier to drugs...

..Taken together, our data indicate that HBHA is able to specifically bind actin, via both its N-terminal and C-terminal domains, strongly suggesting a role of the HBHA-actin interaction in the pathogenesis of mycobacterial diseases...

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..Also, this study suggests that synthetic analogs are excellent candidates for developing new surfactants with tunable, well-defined properties for medical and biotechnological applications...

..fumigatus. The results demonstrate the power of using multiple complementary techniques for probing microbial cell surfaces...

..These single-molecule measurements provide new avenues in pathogenesis research, particularly for elucidating the molecular basis of pathogen-host interactions...

..This work shows how AFM and biophysical methods may help in characterizing drug-membrane interactions, and sheds further light on the mode of action of oritavancin...

..With this Highlight on AFM, it is hoped that more and more microbiologists and biophysicists will take advantage of this powerful, multifunctional nanotechnique...

..These nanoscale analyses open new avenues for understanding the structure of protein monomolecular arrays, which is a crucial challenge in current nanoscience and life science research...

..This study illustrates the potential of real-time atomic force microscopy imaging and force spectroscopy for tracking cell-surface dynamics...

..In parallel, single-molecule force spectroscopy has been used to localize and force probe single cell surface constituents, providing novel insights into their spatial distribution and molecular elasticity...

..Altogether, the results suggest that OatA plays a key role in the spatio-temporal control of septation, irrespective of its catalytic activity...

..Our combined method of AFM with genetic manipulations offers great prospects to explore the mechanisms underlying the clustering of cell surface proteins...

..All together, the data showed that naphthylmethyl neamine derivatives target the membrane of P. aeruginosa. This should offer promising prospects in the search for new antibacterials against drug- or biocide-resistant strains...

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..The entire protocol can be completed in 10 h...

..The nanoscale analyses presented here complement traditional proteomic and molecular biology approaches for the functional analysis of surface-associated proteins, and may help in the search for novel anti-adhesive drugs...

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..The non-invasive live cell experiments presented here open new avenues for understanding the architecture and assembly of peptidoglycan in Gram-positive bacteria...

..In the future, AFM-based nanoscopy should have an important impact on nanomedicine, particularly for understanding microbe-drug and microbe-host interactions, and for developing new antimicrobial strategies...

..Our data suggest that bacterial pili may provide a generic approach in nanobiotechnology for elaborating functional supramolecular interfaces assembled from bioactive building blocks...

..These results demonstrate that mechanical stimuli can trigger adhesion nanodomains in fungal cells and suggest that the force-induced clustering of adhesins may be a mechanism for activating cell adhesion...

..This study shows that AFM imaging can readily discriminate between swarming and non-swarming cells, and quantify their morphological details, thus offering an important tool to study the dynamics of bacterial populations...

..This study provides new insight into the lytic activity of lysostaphin and offers promising prospects for the study of new antistaphylococcal agents...

..In this review, we describe the general principles of the AFM technique, present procedures commonly used to prepare samples and tips, and discuss a number of applications that are relevant to the field of biomaterials...

..These results provide novel insight into the binding forces of bacterial LysMs and show that SMFS is a promising tool for studying the heterologous display of proteins or peptides on bacterial surfaces...

..The single-molecule approach presented here provides new opportunities for understanding the binding mechanisms of antibiotics and for exploring the architecture of bacterial cell walls...

..albicans. The results show that AFM opens up new avenues for understanding the molecular bases of microbe-drug interactions and for developing new therapeutic agents...

..In nanotechnology, these single-molecule manipulation experiments provide new opportunities to understand the molecular mechanisms driving the cohesion of functional amyloid-based nanostructures...

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..These results indicate that AFM is a complementary tool to electron microscopy in that it allows the surface of living cells to be explored directly in real time...

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..The single molecular ruler method presented here not only avoids cell fixation artifacts but also provides new opportunities for studying the dynamics of microbial cell walls during growth, drug action, or enzymatic modification...

..Last, we observed mucilaginous footprints of moderate stiffness (approximately 100 kPa) in the vicinity of ovoid diatoms, which we believe are secreted extracellular polymers...

..All together, differences of ciprofloxacin as compared to moxifloxacin in their interactions with lipids could explain differences in their cellular accumulation and susceptibility to efflux transporters...

..This study demonstrates the power of using multiple complementary AFM modalities for probing the organization and interactions of the various macromolecules of microbial cell walls...

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..We conclude that the NTA-His6 system is a powerful, well-suited platform for the stable, oriented immobilization of proteins in AFM single-molecule studies...

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..The single-molecule experiments presented here offer promising prospects for understanding how microbial pathogens use cell surface molecules to modulate biofilm and immune interactions...

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..In this review, we describe the principles of molecular recognition studies using AFM and provide a flavor of recent progress made in the field...

..These results point to the importance of lipid packing on PLD activity and illustrate the potential of AFM for visualizing remodeling enzymatic activities...

..We expect that the intra- and intermolecular forces measured here may play a significant role in controlling the stability and assembly of the CbsA protein...

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..Here we discuss the problems and challenges that need to be addressed to bring these technologies into living cells and to learn how cellular machinery is controlled in vivo...

..We then mapped the distribution of single HBHA molecules on the surface of living mycobacteria and found that the adhesin is not randomly distributed over the mycobacterial surface, but concentrated into nanodomains...