A5087592261- Advanced Fluorescence Microscopy Techniques
- Force Microscopy Techniques and Applications
- Cellular Mechanics and Interactions
- Near-Field Optical Microscopy
- Cardiomyopathy and Myosin Studies
- Advanced Electron Microscopy Techniques and Applications
- Microfluidic and Bio-sensing Technologies
- Molecular Junctions and Nanostructures
- Photoacoustic and Ultrasonic Imaging
- Orbital Angular Momentum in Optics
- Antibiotic Resistance in Bacteria
- Advanced Biosensing Techniques and Applications
- Image Processing Techniques and Applications
- Bacteriophages and microbial interactions
- Diffusion and Search Dynamics
- Digital Holography and Microscopy
- DNA and Nucleic Acid Chemistry
- Cell Image Analysis Techniques
- Bacterial Identification and Susceptibility Testing
- Lipid Membrane Structure and Behavior
- Cell death mechanisms and regulation
- Mechanical and Optical Resonators
- Mass Spectrometry Techniques and Applications
- Antibiotics Pharmacokinetics and Efficacy
- 3D Printing in Biomedical Research
National Research Council
2018-2025
University of Florence
2014-2025
Instituto de Óptica "Daza de Valdés"
2020-2023
European Theoretical Spectroscopy Facility
2020-2023
National Institute of Optics
2018-2022
National Academies of Sciences, Engineering, and Medicine
2020-2021
WWF Italia
2018
European Centre for Theoretical Studies in Nuclear Physics and Related Areas
2014
Abstract Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation objects, ranging from atoms to space sails. Since the pioneering work by Arthur Ashkin in 1970s, optical have evolved into sophisticated instruments been employed a broad range applications life sciences, physics, engineering. These include accurate force torque measurement at femtonewton level, microrheology complex fluids, single micro- nano-particle spectroscopy, single-cell...
α-catenin is a crucial protein at cell junctions that provides connection between the actin cytoskeleton and membrane. At adherens (AJs), forms heterodimers with β-catenin are believed to resist force on F-actin. Outside AJs, homodimers regulates F-actin organization directly connect membrane cytoskeleton, but their mechanosensitive properties inherently unknown. By using ultra-fast laser tweezers we found single α-β-catenin heterodimer does not instead slips along in direction of force....
Abstract The dynamics of cellular membrane tension and its role in mechanosensing, which is the ability cells to respond physical stimuli, remain incompletely understood, mainly due lack appropriate tools. Here, we report a force-controlled nanopipette-based method that combines fluidic force microscopy with fluorescence imaging for precise manipulation while monitoring impact on single-cell mechanosensitivity. nanopipette enables control indentation imposed cell cortex as well aspiration...
ABSTRACT The increasing demand for sensitive, portable, and affordable disease detection methods has spurred the development of advanced biosensors rapid early‐stage diagnosis, population mass screening, bed‐monitoring. Current high‐sensitivity devices face hurdles such as high production costs challenges in multiplexed signal detection. To address these, we developed a prism‐based total internal reflection system which, combination with surface functionalization techniques gold...
Abstract Live cells are three-dimensional environments where biological molecules move to find their targets and accomplish functions. However, up now, most single molecule investigations have been limited bi-dimensional studies owing the complexity of 3d-tracking techniques. Here, we present a novel method for localization nano-emitters based on automatic recognition out-of-focus diffraction patterns. Our technique can be applied track movements in living using conventional epifluorescence...
The mitogen‐activated protein kinase (MAPK) extracellular signal‐regulated 5 (ERK5) is emerging as a promising target in cancer. Indeed, alterations of the MEK5/ERK5 pathway are present many types cancer, including melanoma. One key events MAPK signalling nuclear translocation and its subsequent regulation gene expression. Likewise, effects ERK5 supporting cancer cell proliferation have been linked to localization. Despite processes regulating having determined, transporters involved not yet...
Abstract Bacterial biofilms are highly complex communities in which isogenic bacteria display different gene expression patterns and organize a three-dimensional mesh gaining enhanced resistance to biocides. The molecular mechanisms behind such increased remain mostly unknown, also because of the technical difficulties biofilm investigation at sub-cellular level. In this work we focus on AcrAB-TolC protein complex, multidrug efflux pump found Enterobacteriaceae, whose overexpression is...
In any living cell, genome maintenance is carried out by DNA-binding proteins that recognize specific sequences among a vast amount of DNA. This includes fundamental processes such as DNA replication, repair, and gene expression regulation. Here, we study the mechanism target search single lac repressor protein (LacI) with ultrafast force-clamp spectroscopy, sub-millisecond few base-pair resolution technique based on laser tweezers. We measure 1D-diffusion at physiological salt...
Myosin-5B is one of three members the myosin-5 family actin-based molecular motors. Despite its fundamental role in recycling endosome trafficking and collective actin network dynamics, mechanisms underlying motility are inherently unknown. Here we combine single-molecule imaging high-speed laser tweezers to dissect mechanoenzymatic properties myosin-5B. We show that a single myosin-5B moves processively 36-nm steps, stalls at ~2 pN resistive forces, reverses directionality forces >2 pN....
In HILO microscopy, a highly inclined and laminated light sheet is used to illuminate the sample, thus drastically reducing background fluorescence in wide-field but maintaining simplicity of use single objective for both illumination detection. Although technique has become widely popular, particularly molecule super-resolution limited understanding how finely shape beam this impacts on image quality complicates setting fit experimental needs. work, we build up simple comprehensive guide...
ABSTRACT The increasing demand for sensitive, portable, and cost-effective disease detection methods has raised significant interest in the development of biosensors rapid early-stage diagnosis, population mass-screening, bedside monitoring. Although a certain number sensing devices with high sensitivity experienced considerable progress, their practical application been hindered by challenges replicating instrumental systems, obtaining multiplexed signals, cost manufacturing. In response,...
Myosin is a large family of actin-based molecular motors, which includes efficient intracellular transporters that move cargoes and material essential for cell's life. Here, we describe protocols labelling single myosin motors with quantum dots, tracking them in an vitro reconstituted single-molecule motility assay, acquiring image stacks analyzing them. We the required steps to obtain trajectories from fundamental biophysical parameters such as motor velocity, run length step size can be...
MDR in bacteria is threatening to public health. Overexpression of efflux pumps an important cause MDR. The co-administration antimicrobial drugs and pump inhibitors (EPIs) a promising approach address the problem MDR.To identify new putative EPIs characterize their mechanisms action.The effects four selected piperazine derivatives on resistance-nodulation-cell division (RND) was evaluated Escherichia coli strains overexpressing or not expressing RND by assays aimed at evaluating antibiotic...
Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation objects ranging from atoms to space sails. Since the pioneering work by Arthur Ashkin in 1970s, optical have evolved into sophisticated instruments been employed a broad range applications life sciences, physics, engineering. These include accurate force torque measurement at femtonewton level, microrheology complex fluids, single micro- nanoparticle spectroscopy, single-cell analysis,...
Particle localization plays a fundamental role in advanced biological techniques such as single-molecule tracking, superresolution microscopy, and manipulation by optical magnetic tweezers. Such require fast accurate particle algorithms well nanometer-scale stability of the microscope. Here, we present universal method for three-dimensional single labeled unlabeled particles based on local gradient calculation images. The outperforms state-of-the-art high-noise conditions, it is capable 3D...
Aim: To investigate the action mechanism of 1-benzyl-1,4-diazepane (1-BD) as efflux pump inhibitor (EPI) in Escherichia coli mutants: ΔacrAB or overexpressing AcrAB and AcrEF pumps. Materials & methods: Effect 1-BD on: antibiotic potentiation, by microdilution method; membrane functionality, fluorimetric assays; ethidium bromide accumulation, fluorometric real-time assay; AcrB expression, quantitative photoactivated localization microscopy. Results: decreases minimal inhibitory concentration...
α-catenin is a crucial protein at cell junctions that provides connection between the actin cytoskeleton and membrane. At adherens (AJs), forms heterodimers with β-catenin are believed to resist force on F-actin. Outside AJs, homodimers directly connect membrane cytoskeleton, but their mechanosensitive properties inherently unknown. Surprisingly, by using ultra-fast laser tweezers we found single α-β-catenin heterodimer does not instead slips along F-actin in direction of force. Conversely,...
Innovative liquid biopsy technologies, exploiting total internal reflection spectroscopy, enable highly sensitive biomarkers detection. A compact, low-cost microscope exhibiting impressive detection limits and reproducibility was built, making it a promising diagnostic tool for real-time disease monitoring, applicable to human biofluids.