Article16 November 2018Open Access Transparent process A conserved mechanism drives partition complex assembly on bacterial chromosomes and plasmids Roxanne E Debaugny Laboratoire de Microbiologie et Génétique Moléculaires, Centre Biologie Intégrative (CBI), National la Recherche Scientifique (CNRS), Université Toulouse, UPS, France Search for more papers by this author Aurore Sanchez Jérôme Rech Delphine Labourdette LISBP, CNRS, INRA, INSA, Dorignac Charles Coulomb, CNRS-Université...

Efficient bacterial chromosome segregation typically requires the coordinated action of a three-component machinery, fueled by adenosine triphosphate, called partition complex. We present phenomenological model accounting for dynamic activity this system that is also relevant physics catalytic particles in active environments. The obtained coupling simple linear reaction-diffusion equations with proteophoresis, or "volumetric" chemophoresis, force field arises from protein-protein...

Dynamical response of nanomechanical cantilever structures immersed in a viscous fluid is important to vitro single-molecule force spectroscopy, biomolecular recognition disease-specific proteins, and the study microscopic protein dynamics. Here we stochastic biofunctionalized beams fluid. Using fluctuation-dissipation theorem derive an exact expression for spectral density displacement linear approximation resonance frequency shift. We find that solution shift nanoscale determined by...

We study the effect of discrete breathers (DBs) on transfer a Bose-Einstein condensate (BEC) in an optical lattice using nonlinear Schr\"odinger equation. In previous theoretical (primarily numerical) investigations dynamics BECs leaking lattices, collisions between DB and excitation, e.g., moving breather (MB) or phonon, were studied. These led to transmission fraction incident (atomic) norm MB through DB, while can be shifted direction excitation. Here we develop analytic understanding...

The spectrum of the quantum discrete nonlinear Schrödinger equation, or boson Hubbard Hamiltonian, on a periodic 1D lattice shows some interesting detailed band structure, which may be interpreted as signature two-breather interaction in classical case. This fine structure is studied using degenerate perturbation theory. We also present modification to this model, increases mobility bound states.

Bacterial ParB partitioning proteins involved in chromosomes and low-copy-number plasmid segregation are cytosine triphosphate (CTP)-dependent molecular switches. CTP-binding converts dimers to DNA clamps, allowing unidimensional diffusion along the DNA. This sliding property has been proposed explain spreading over large distances from parS centromere sites where is specifically loaded. We modeled such a "clamping sliding" mechanism as typical reaction-diffusion system, compared it F...

A method is proposed to solve the challenging problem of determining supratransmission threshold (onset instability harmonic boundary driving inside a band gap) in multicomponent nonintegrable nonlinear systems. It successfully applied degenerate three-wave resonant interaction birefringent quadratic medium where process generates spatial gap solitons. No analytic expression known for this model showing broad applicability

A method is proposed to generate and study the dynamics of spatial light solitons in a birefringent medium with quadratic nonlinearity. Although no analytical expression for propagating has been obtained, our numerical simulations show existence stable localized frequency forbidden band gap medium. The these objects quite rich manifests instance elastic reflections, or inelastic collisions where two merge propagate as single solitary wave. We derive slowly varying envelopes three fields...

We report direct measurements of average vibration energy in a high frequency flexural resonance mode achieved via an-harmonic elastic coupling to fundamental nanomechanical resonator. The second order effect produces shift the read-out as function mean square excitation amplitude mode. measure shifts at lowest driving amplitudes, down noise floor experimental setup. With implementation existing ultra-sensitive amplifiers, reported technique will enable quantized transitions low-thermal...

Abstract Translation is one of the main steps in synthesis proteins. It consists ribosomes that translate sequences nucleotides encoded on mRNA into polypeptide amino acids. Ribosomes bound to move unidirectionally, while unbound diffuse cytoplasm. has been hypothesized finite diffusion plays an important role ribosome recycling and circularization enhances efficiency translation, see e.g. Lodish et al. (Molecular cell biology, 8th edn, W.H. Freeman Company, San Francisco, 2016). In order...

ParAB S , the most widespread bacterial DNA segregation system, is composed of a centromeric sequence, parS and two proteins, ParA ATPase ParB binding proteins. Hundreds proteins assemble dynamically to form nucleoprotein -anchored complexes that serve as substrates for molecules catalyze positioning events. The exact nature this complex has remained elusive, what we address here by revisiting Stochastic Binding model (SBM) introduced explain non-specific profile in vicinity . In SBM, loops...

We study the Aharonov-Bohm effect for an exciton on a nanoring using 2D attractive fermionic Hubbard model. extend previous results obtained 1D ring, in which only azimuthal motion is considered, to more general case of annular lattices. In general, we show that existence localization effect, increased by nonlinearity, makes phenomenon system similar case. However, introduction radial introduces extra frequencies, different from original isolated frequency corresponding excitonic...

In this paper, the quantum spectrum of isochronous potentials is investigated. Given that frequency classical motion in such energy-independent, it natural to expect their spectra be equispaced. However, as has already been shown some specific examples, property not always true. To gain general insight into problem, a WKB analysis spectrum, valid for any analytic potential, performed and first semiclassical corrections its regular spacing are calculated. We illustrate results on...

The bacterial flagellar motor is the membrane-embedded rotary motor, which turns flagellum that provides thrust to many bacteria. This large multimeric complex, composed of a few dozen constituent proteins, hallmark dynamic subunit exchange. stator units are inner-membrane ion channels dynamically bind peptidoglycan at rotor periphery and apply torque. Their exchange function viscous load on flagellum, allowing bacterium adapt its local environment, although molecular mechanisms...

We analyze the quantum properties of a system consisting two nonlinearly coupled pendulums. This nonintegrable exhibits different symmetries: permutational symmetry and another one related to reversal total momentum system. Each these symmetries is responsible for existence kinds quasidegenerate states. At sufficiently high energy, pairs symmetry-related states glue together form quadruplets. show that, starting from anticontinuous limit, particular quadruplets allow us construct whose are...

The bacterial genome is organized in a structure called the nucleoid by variety of associated proteins. These proteins can form complexes on DNA that play central role various biological processes, including chromosome segregation. A prominent example large ParB-DNA complex, which forms an essential component segregation machinery many bacteria. ChIP-Seq experiments show ParB localize around centromere-like parS sites to binds specifically, and spreads from there over sections chromosome....

Abstract In order to study colour signals as animals perceive them, visual ecologists usually rely on models of vision that do not consider patterns–the spatial arrangement features within a signal. HMAX describes family are used pattern perception in human research, and which have inspired many artificial intelligence algorithms. this article, we highlight the sensory brain mechanisms modelled widespread, occurring most if all vertebrates, thus offering wide range applications ecology. We...

We develop a simple continuum model to analyze the vibrational modes of nanomechanical multielement structure. In this model, arrays submicron cantilevers located symmetrically on both sides central clamped-clamped nanobeam are replaced by continuum. approach, equations motion structure become exactly solvable. Our analytical results capture main features observed numerically and experimentally can be applied general class scale-independent elasticaly coupled resonator structures.

We propose a general one-dimensional continuous formulation to analyze the vibrational modes of antennalike nanomechanical resonators consisting two symmetric arrays cantilevers affixed central nanobeam. The cantilever can have arbitrary density and length profile along beam. obtain secular equation that allows for determination their frequency spectrum illustrate results on particular examples structures with constant or alternating profiles. show our analytical capture vibration such...

We address the question of time needed by $N$ particles, initially located on first sites a finite one-dimensional lattice size $L$, to exit that when they move according TASEP transport model. Using analytical calculations and numerical simulations, we show $N\ensuremath{\ll}L$, mean particles is asymptotically given ${T}_{N}(L)\ensuremath{\sim}L+{\ensuremath{\beta}}_{N}\sqrt{L}$ for large lattices. Building upon exact results obtained two devise an approximate continuous space description...

The anticontinuum limit (i.e. the of weakly coupled oscillators) is used to obtain two surprising results. First we prove continuation discrete breathers interacting harmonic oscillators, provided a suitable coupling chosen. Secondly derive an analytical result for wave transmission by breather nonlinear Schrödinger equation at weak coupling. We resonant full reflection due Fano resonance.

Abstract Bacterial ParB partitioning proteins involved in chromosomes and low-copy-number plasmid segregation have recently been shown to belong a new class of CTP-dependent molecular switches. Strikingly, CTP binding hydrolysis was induce conformational change enabling dimers switch between an open closed conformation. This latter conformation clamps on DNA molecules, allowing their diffusion one dimension along the DNA. It has proposed that this novel sliding property may explain spreading...