Abstract Biopolymer topology is critical for determining interactions inside cell environments, exemplified by DNA where its response to mechanical perturbation as important biochemical properties cellular roles. The dynamic structures of chiral biopolymers exhibit complex dependence with extension and torsion, however the physical mechanisms underpinning emergence structural motifs upon physiological twisting stretching are poorly understood due technological limitations in correlating...

AT-rich motifs can generate extreme mechanical properties, which are critical for creating strong global bends when phased properly.

The RecA protein and RecBCD complex are key bacterial components for the maintenance repair of DNA. is a helicase-nuclease that uses homologous recombination to resolve double-stranded DNA breaks. It also facilitates coating single-stranded with form filaments, vital step in break pathway. However, questions remain about mechanistic roles live cells. Here, we use millisecond super-resolved fluorescence microscopy pinpoint spatial localization fluorescent reporters or RecB at physiological...

As camera pixel arrays have grown larger and faster, optical microscopy techniques ever more refined, there has been an explosion in the quantity of data acquired during routine light microscopy. At single-molecule level, analysis involves multiple steps can rapidly become computationally expensive, some cases intractable on office workstations. Complex bespoke software present high activation barriers to entry for new users. Here, we redevelop our quantitative routines into optimized...

The double-helical structure of DNA results from canonical base pairing and stacking interactions. However, variations steady-state conformations resulting mechanical perturbations in cells have physiological relevance but their dependence on sequence remains unclear. Here, we use molecular dynamics simulations showing differences result markedly different structural motifs upon twisting stretching. We simulate overextension sequences ((AA)12, (AT)12, (CC)12 (CG)12) with supercoiling...

Abstract Super-resolution microscopy has catalyzed valuable insights into the sub-cellular, mechanistic details of many different biological processes across a wide range cell types. Fluorescence polarization spectroscopy tools have also enabled important cellular through identifying orientational changes molecules typically at an ensemble level. Here, we combine these two biophysical methodologies in single home-made instrument to enable simultaneous detection orthogonal fluorescence...

In eukaryotes, intracellular physico-chemical properties like macromolecular crowding and cytoplasmic viscoelasticity influence key processes such as metabolic activities, molecular diffusion protein folding. However, mapping in living cells remains challenging. One approach uses passive rheology which of exogenous fluorescent particles internalized is tracked inferred from derived mean square displacement relations. Recently, the crGE2.3 Förster resonance energy transfer biosensor was...

The pandemic profoundly disrupted university students’ lives. Many students have parenting and/or caring responsibilities and work part-time jobs. Undergraduate cohorts today are extremely diverse, comprised of people from a wide range social, ethnic, economical cultural backgrounds. Research has highlighted the different ways affected lives globally. During lockdown(s) universities responded swiftly to needs enabling them continue with their studies, though such responses were reactive...

The Fredholm integral equation method is applied to the scattering of electromagnetic waves by finite dielectric cylinders circular cross section. a wide range diameter/length ratios, including both rods and discs. Generally good agreement has been obtained with experimental backscatter measurements McCormick Hendry.

It is shown that expressions, giving the forward and backward scattering amplitudes for of electromagnetic waves by arbitrarily orientated spheroids in terms respective incidence along principal axes, hold under various approximations. The Van der Hulst approximation (1957) derived.

Lipid vesicles are valuable mesoscale molecular confinement vessels for studying membrane mechanics and lipid-protein interactions, they have found utility among bio-inspired technologies, including drug delivery vehicles. While vesicle morphology can be modified by changing the lipid composition introducing fusion or pore-forming proteins detergents, influence of extramembrane crowding on has remained under-explored owing to a lack experimental tools capable capturing morphological changes...

The combination of DNA force spectroscopy and polarization microscopy fluorescent intercalator dyes can provide valuable insights into the structure under tension. These techniques have previously been used to characterize S-DNA—an elongated conformation that forms when overstretches at forces ≥ 65 pN. In this way, it was deduced base pairs S-DNA are highly inclined, relative those in relaxed (B-form) DNA. However, is unclear whether how topological constraints on may influence base-pair...

Lithium salts are used in the treatment of mood disorders, cancer, and Alzheimer's disease. It has been shown to prolong life span several phyla; however, not yet budding yeast. In our study, we investigate influence lithium on yeast cells' viability by characterizing protein aggregate formation, cell volume, molecular crowding context stress adaptation. While data suggest a concentration-dependent growth inhibition caused LiCl, show an extended long-term survival rate as effect addition...

Abstract Biopolymer topology is critical for determining interactions inside cell environments, exemplified by DNA where its response to mechanical perturbation as important biochemical properties cellular roles. The dynamic structures of chiral biopolymers exhibit complex dependence with extension and torsion, however the physical mechanisms underpinning emergence structural motifs upon physiological twisting stretching are poorly understood due technological limitations in correlating...

Biopolymer topology is critical for determining interactions inside cell environments, exemplified by DNA where its response to mechanical perturbation as important biochemical properties cellular roles. The dynamic structures of chiral biopolymers exhibit complex dependence with extension and torsion, however the physical mechanisms underpinning emergence structural motifs upon physiological twisting stretching are poorly understood due technological limitations in correlating force, torque...

Abstract As camera pixel arrays have grown larger and faster, optical microscopy techniques ever more refined, there has been an explosion in the quantity of data acquired during routine light microcopy. At single-molecule level, analysis involves multiple steps can rapidly become computationally expensive, some cases intractable on office workstations. Complex bespoke software present high activation barriers to entry for new users. Here, we redevelop our quantitative routines into...

Abstract The RecA protein and RecBCD complex are key bacterial components for the maintenance repair of DNA. is a helicase-nuclease that uses homologous recombination to resolve double-stranded DNA breaks. It also facilitates coating single-stranded with form filaments, vital step in break pathway. However, questions remain about mechanistic roles live cells. Here, we use millisecond super-resolved fluorescence microscopy pinpoint spatial localization fluorescent reporters or RecB at...

The RecA protein and RecBCD complex are key bacterial components for the maintenance repair of DNA, a helicase-nuclease that uses homologous recombination to resolve double-stranded DNA breaks also facilitating decoration single-stranded with form filaments, vital step in break pathway. However, questions remain about mechanistic roles live cells. Here, we use millisecond super-resolved fluorescence microscopy pinpoint spatial localization fluorescent reporters RecB at physiological levels...