Related papers: Osmotic pressure: resisting or promoting DNA eject…
A critical step in the bacteriophage life cycle is genome ejection into host bacteria. The ejection process for double-stranded DNA phages has been studied thoroughly \textit{in vitro}, where after triggering with the cellular receptor the…
Bacteriophages, phages for short, are viruses of bacteria. The majority of phages contain a double-stranded DNA genome packaged in a capsid at a density of ~500 mg/ml. This high density requires substantial compression of the normal B form…
We discuss how a balance can be established between the force acting to eject DNA from viral capsids and the force resisting its entry into a colloidal suspension which mimics the host cell cytoplasm. The ejection force arises from the…
The ejection of DNA from a bacterial virus (``phage'') into its host cell is a biologically important example of the translocation of a macromolecular chain along its length through a membrane. The simplest mechanism for this motion is…
We present in this work in vitro measurements of the force ejecting DNA from two distinct bacteriophages (T5 and lambda) using the smotic-suppression technique. Our data are analyzed by revisiting the current theories of DNA packaging in…
Several controversial issues concerning the packing of linear DNA in bacteriophages and globules are discussed. Exact relations for the osmotic pressure, capsid pressure and loading force are derived in terms of the hole size inside phages…
The conjunction of insights from structural biology, solution biochemistry, genetics and single molecule biophysics has provided a renewed impetus for the construction of quantitative models of biological processes. One area that has been a…
We study the control parameters that govern the dynamics of in vitro DNA ejection in bacteriophage lambda. Past work has demonstrated that bacteriophage DNA is highly pressurized; this pressure has been hypothesized to help drive DNA…
A variety of viruses tightly pack their genetic material into protein capsids that are barely large enough to enclose the genome. In particular, in bacteriophages, forces as high as 60 pN are encountered during packaging and ejection,…
Most bacteriophages are known to inject their double-stranded DNA into bacteria upon receptor binding in an essentially spontaneous way. This downhill thermodynamic process from the intact virion toward the empty viral capsid plus released…
The role of thermal pressure fluctuations in the ejection of tightly packaged DNA from protein capsid shells is discussed in a model calculation. At equilibrium before ejection we assume the DNA is folded many times into a bundle of…
The role of thermal pressure fluctuation excited within tightly packaged DNA prior to ejection from protein capsid shells is discussed in a model calculation. At equilibrium before ejection we assume the DNA is folded many times into a…
Encapsulation of dsDNA fragments (contour length 54 nm) by the cationic diblock copolymer poly(butadiene-b-N-methyl 4-vinyl pyridinium) [PBd-b-P4VPQ] has been studied with phase contrast, polarized light, and fluorescence microscopy, as…
The problem of inhibiting viral DNA ejection from bacteriophages by multivalent counterions, specifically Mg$^{+2}$ counterions, is studied. Experimentally, it is known that MgSO$_4$ salt has a strong and non-monotonic effect on the amount…
Foams exhibit absorptive properties and are widely used for cleaning contaminants, oil recovery, and selective mineral extraction via froth flotation. Although foam absorption has historically been linked to equilibrium osmotic pressure,…
The volume occupied by unconstrained bacterial DNA in physiological solutions exceeds 1000 times the volume of the cell. Still, it is confined to a well defined region of the cell called the nucleoid, which occupies only a fraction of the…
By equilibrating condensed DNA arrays against reservoirs of known osmotic stress and examining them with several structural probes, it has been possible to achieve a detailed thermodynamic and structural characterization of the change…
The impact of damping effect and external forces to the DNA breathing is investigated within the Peyrard-Bishop model. In in the continuum limit, the dynamics of the breathing of DNA is described by the forced-damped nonlinear Schrodinger…
Bacteriophages infect cells by attaching to the outer membrane and injecting their DNA into the cell.The phage DNA is then transcribed by the cell's transcription machinery.A number of physical mechanisms by which DNA can be translocated…
We characterize the equilibrium thermodynamics of a thick polymer confined in a spherical region of space. This is used to gain insight into the DNA packaging process. The experimental reference system for the present study is the recent…