Abstract The cell wall is a shape-defining structure that envelopes almost all bacteria and protects them from environmental stresses. Bacteria can be forced to grow without under certain conditions interfere with synthesis, but the relevance of these wall-less cells (known as L-forms) unclear. Here, we show several species filamentous actinomycetes have natural ability generate wall-deficient in response hyperosmotic stress, which call S-cells. This state transient, S-cells are able switch...

Recent experimental studies have demonstrated that cellular motion can be directed by topographical gradients, such as those resulting from spatial variations in the features of a micropatterned substrate. This phenomenon, known topotaxis, has been extensively studied for gradients at subcellular scale, but also occur presence spatially varying density cell-sized features. Such large-scale topotaxis recently observed highly motile cells persistently crawl within an array obstacles with...

Abstract A major challenge in the use of HepG2 cell culture models for drug toxicity screening is their lack maturity 2D culture. 3D Matrigel promotes formation spheroids that express liver‐relevant markers, yet they still various primary hepatocyte functions. Therefore, alternative matrices where chemical composition and materials properties are controlled to steer maturation remain desired. Herein, a modular approach taken based on fully synthetic minimalistic supramolecular matrix...

Supramolecular materials provide unique opportunities to mimic both the structure and mechanics of biopolymer networks that compose extracellular matrix. However, strategies modify their filamentous structures in space time 3D cell culture study behavior as encountered development disease are lacking. We herein disclose a multicomponent squaramide-based supramolecular material whose bioactivity can be controlled by light through co-assembly 1,2-dithiolane (DT) monomer forms disulfide...

Photochemical ligation strategies in hydrogel materials are crucial to model spatiotemporal phenomena that occur the natural extracellular matrix. We here describe use of cyclic 1,2-dithiolanes cross-link with norbornene on linear poly(ethylene glycol) polymers through UV irradiation a rapid and byproduct-free manner, resulting branched macromolecular architectures from low-viscosity precursor solutions. Oscillatory rheology NMR data indicate one-pot formation thioether disulfide...

Due to the sequence-dependent nature of elasticity DNA, many protein-DNA complexes and other systems in which DNA molecules must be deformed have preferences for type sequence they interact with. SELEX (Systematic Evolution Ligands by EXponential enrichment) experiments similar selection been used extensively examine (indirect readout) of, e.g., nucleosomes (protein spools around is wound compactification) rings. We show how recently developed computational theoretical tools can emulate such...

The primary defence mechanism of myocytes against peroxides and peroxide-derived peroxyl alkoxyl radicals is the glutathione redox cycle. purpose present study was to increase turnover rate this cycle by stimulating peroxidase catalysed reaction (2GSH-->GSSG), reductase (GSSG-->2GSH), or both. Neonatal rat heart cell cultures were subjected a standardized protocol oxidative stress using 80 mumol.l-1 cumene hydroperoxide (CHPO) for 0-90 min. consequences described in terms cellular...

Abstract Cells encounter a wide variety of physical and chemical cues when navigating their native environments. However, response to multiple simultaneous is not yet clear. In particular, the influence topography, in presence chemotactic gradient, on migratory behavior understudied. Here, we investigate effects topographical guidance highly motile amoeboid cell migration (topotaxis) generated by asymmetrically placed micropillars. The micropillar field allows for an additional, natural...

Nucleic acid-polymer conjugates are an attractive class of materials endowed with tunable and responsive character. Herein, we exploit the dynamic character nucleic acids in preparation hybrid DNA-covalent polymers extendable grafts by hybridization chain reaction. Addition DNA hairpins to initiator DNA-dextran graft copolymer resulted growth as evidenced various characterization techniques over several length scales. Additionally, aggregation DNA-graft before reaction was observed resulting...

Abstract The application of double electron‐electron resonance (DEER) with site‐directed spin labeling (SDSL) to measure distances in proteins and protein complexes living cells puts rigorous restraints on the spin‐label. linkage paramagnetic centers need resist reducing conditions cell. Rigid attachment probe improves precision measured distances. Here, three two‐armed Gd III complexes, ‐CLaNP13a/b/c were synthesized. Rather than disulfide most other CLaNP molecules, a thioether was used...

Intracellular transport is pivotal for cell growth and survival. Malfunctions in this process have been associated with devastating neurodegenerative diseases, highlighting the need a deeper understanding of mechanisms involved. Here, we use an experimental methodology that leads neurites differentiated PC12 cells into either one two configurations: one-dimensional configuration, where align along lines, or two-dimensional adopt random orientation shape on flat substrate. We subsequently...

Abstract Intracellular transport is pivotal for cell growth and survival. Malfunctions in this process have been associated with devastating neurodegenerative diseases, posing a need deeper understanding of the involved mechanisms. Here, we used an experimental methodology that lead neurites differentiated PC12 cells either two configurations: one-dimensional, where align along lines, or two-dimensional configuration, adopt random orientation shape on fiat substrate. We subsequently...

In vivo, cells navigate through complex environments filled with obstacles. Recently, the term 'topotaxis' has been introduced for navigation along topographic cues such as obstacle density gradients. Experimental and mathematical efforts have analyzed topotaxis of single in pillared grids pillar A previous model based on active Brownian particles shown that ABPs perform topotaxis, i.e., drift towards lower densities, due to decreased effective persistence lengths at high pillars densities....

Abstract The G 4 C 2 hexanucleotide repeat expansion in the c9orf72 locus is one among a plethora of mutations associated with amyotrophic lateral sclerosis. It accounts for majority disease cases. exact processes underlying pathology this mutation remain elusive, yet recent evidence suggests mechanism that disrupts axonal trafficking. Here, we used neuronal cell line and without repeats, implemented time-resolved local mean squared displacement analysis to characterize motion lysosomes...