Publications de Giovanni Dietler

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Using single-molecule force-clamp spectroscopy, where the distance between the AFM tip and the sample surface is fixed and a few parallel avidin-biotin complexes are kept stretched by a certain force, we were able to observe the formation of single avidin- ...

Yeast resistance to antifungal drugs is a major public health issue. Fungal adhesion onto the host mucosal surface is still a partially unknown phenomenon that is modulated by several actors among which fibronectin plays an important role. Targeting the ye ...

The atomic force microscopy in ultrahigh vacuum and at low temperature demonstrated its excellent capability to reach atomic resolution. Nevertheless in the case of biological samples high resolution has been achieved only in very few cases. We demonstrated here the importance of the appropriate choice of probes and substrates in order to image DNA at low temperature with high resolution. We investigated properties of three types of cantilevers and they were studied by scanning electron microscopy as a func

The cytoskeleton is a highly dynamical protein network that plays a central role in numerous cellular physiological processes, and is traditionally divided into three components according to its chemical composition, i.e. actin, tubulin and intermediate fi ...

We performed dynamic force spectroscopy of single dextran and titin 127 molecules using small-amplitude and low-frequency (40-240 Hz) dithering of an atomic force microscope tip excited by a sine wave voltage fed onto the tip-carrying piezo. We show that f ...

A novel method for quantitative lateral force measurement (LFM) calibration has been developed. Using a single-molecule spectroscopy approach it is possible to calibrate the AFM levers for both lateral and normal spring constants with a single image scan. ...

Amyloid fibrils associated with neurodegenerative diseases, such as Parkinson's and Alzheimer's, consist of insoluble aggregates of α-synuclein and Aβ-42 proteins with a high β-sheet content. The aggregation of both proteins occurs by misfolding of the monomers and proceeds through the formation of intermediate oligomeric and protofibrillar species to give the final fibrillar cross-β-sheet structure. The morphological and mechanical properties of oligomers, protofibrils, and fibrils formed during the fibril

DNA in bacterial chromosomes and bacterial plasmids is supercoiled. DNA supercoiling is essential for DNA replication and gene regulation. However, the density of supercoiling in vivo is circa twice smaller than in deproteinized DNA molecules isolated from ...

We present a programmable microcontroller-driven injection system for the exchange of imaging medium during atomic force microscopy. Using this low-noise system, high-resolution imaging can be performed during this process of injection without disturbance. ...

Amyloids are insoluble protein fibrillar aggregates. The importance of characterizing their aggregation has steadily increased because of their link to human diseases and material science applications. In particular, misfolding and aggregation of the Josep ...

Two-dimensional semiflexible polymer rings are studied both by imaging circular DNA adsorbed on a mica surface and by Monte Carlo simulations of phantom polymers as well as of polymers with finite thickness. Comparison of size and shape of the different mo ...

Amyloid polymorphism is a hallmark of almost all amyloid species, yet the mechanisms underlying the formation of amyloid polymorphs and their complex architectures remain elusive. Commonly, two main mesoscopic topologies are found in amyloid polymorphs cha ...

Over the last two decades, the identification of missense mutations in the alpha-synuclein (alpha-Syn) gene SNCA in families with inherited Parkinson disease (PD) has reinforced the central role of alpha-Syn in PD pathogenesis. Recently, a new missense mut ...

The insurgence of newly arising, rapidly developing health threats, such as drug-resistant bacteria and cancers, is one of the most urgent public-health issues of modern times. This menace calls for the development of sensitive and reliable diagnostic tool ...

We have synthesized a 17-mer peptide (ER17p) that is issued from the hinge region of the estrogen receptor and which activates the proliferation of breast carcinoma cells in steroid-deprived conditions. In the present paper, we show that at a concentration ...

Atomic force microscopy is being increasingly used to explore the physical properties of biological structures. This technique involves the application of a force to the sample and a monitoring of the ensuing deformation process. The available experimental ...

We discuss scanning near-field optical microscope based on original double resonant montage of a fibre probe onto the tuning fork and proprietary electronics capable of fast and precise measurements of the resonant frequency and the quality factor of senso ...

Some preliminary results and experimental details of Near-field Scanning Optical Microscopy (NSOM) operation in liquids have been reported by us earlier(1-4). Here we present the first use of custom made polystyrene/poly (methyl methacrylate) (PMMA) optica ...

Long double stranded DNA (DsDNA) and single stranded DNA (ssDNA) molecules were studied by direct imaging with the Atomic Force Microscope (AFM) in order to determine their scaling properties, exponents, distributions and persistence length in the frame work of the theory of polymer physics and at the single molecule level. The effects of the topology on the statistical properties were investigated by considering linear, circular and knotted DNA molecules

A label-free biosensor device based on registration of photonic crystal surface waves is described. Angular interrogation of the optical surface wave resonance is used to detect changes in the thickness of an adsorbed layer, while an additional simultaneou ...

Giovanni Dietler

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Single-molecule avidin-biotin association reaction studied by force-clamp spectroscopy

Yeast Nanometric Scale Oscillations Highlights Fibronectin Induced Changes in C. albicans

Study of probes and substrates for low temperature atomic force microscopy and biological applications

A Robust Actin Filaments Image Analysis Framework

Can Dissipative Properties of Single Molecules Be Extracted from a Force Spectroscopy Experiment?

A single-molecule stretching method for lateral and normal AFM lever calibration

Influence of the β-sheet content on the mechanical properties of aggregates during amyloid fibrillization

Effects of physiological self-crowding of DNA on shape and biological properties of DNA molecules with various levels of supercoiling

Microcontroller-driven fluid-injection system for atomic force microscopy

Infrared nanospectroscopy characterization of oligomeric and fibrillar aggregates during amyloid formation

Excluded Volume Effects on Semiflexible Ring Polymers

Hierarchical Protofilament Intertwining Rules the Formation of Mixed‐Curvature Amyloid Polymorphs

The H50Q Mutation Enhances alpha-Synuclein Aggregation, Secretion, and Toxicity

A perspective view on the nanomotion detection of living organisms and its features

Concentration-dependent and surface-assisted self-assembly properties of a bioactive estrogen receptor alpha-derived peptide

Probing nanomechanical properties from biomolecules to living cells

Scanning near-field optical microscope based on a double resonant fibre probe montage and equipped with time-gated photon detection

Chemically etched plastic optical fiber probe for near-field scanning optical microscopy in liquids

Scaling of double and single stranded DNA

Photonic Crystal Biosensor Based on Optical Surface Waves