Extracellular Matrix Components and Mechanosensing Pathways in Health and Disease.

Glycosaminoglycans (GAGs) and proteoglycans (PGs) are essential components of the extracellular matrix (ECM) with pivotal roles in cellular mechanosensing pathways. GAGs, such as heparan sulfate (HS) and chondroitin sulfate (CS), interact with various cell surface receptors, including integrins and receptor tyrosine kinases, to modulate cellular responses to mechanical stimuli. PGs, comprising a core protein with covalently attached GAG chains, serve as dynamic regulators of tissue mechanics and cell behavior, thereby playing a crucial role in maintaining tissue homeostasis.

Production of unsulfated chondroitin and associated chondro-oligosaccharides in recombinant Escherichia coli.

We designed metabolically engineered non-pathogenic strains of Escherichia coli to produce unsulfated chondroitin with and without chondroitin lyase to produce the chondroitin polymer or its related oligosaccharides. Chondroitin was synthesized using chondroitin synthase KfoC and chondroitin was degraded using Pl35, a chondroitin lyase from Pedobacter heparinus. Pl35 behaved as a true endo-enzyme generating a large panel of oligosaccharides ranging from trimers to 18-mers instead of the di- and tetramers obtained with most chondroitin lyases.

Computational modeling of protein-carbohydrate interactions: Current trends and future challenges.

The article leads the reader through an up-to-date presentation of the concepts, developments, and main applications of computational modeling to study protein-carbohydrate interactions. It follows with the presentation of some current issues and perspectives arising from the expected evolution of generic methodological developments in deep learning, immersive analytics, and virtual reality for molecular visualization and data management. Such methodological developments for macromolecular interactions would greatly benefit a wide range of scientific endeavors in the field of carbohydrate chemistry and biochemistry, including the following interrelated efforts dealing with highly crowded media, with examples concerning glycoside transferases, the extracellular matrix, and the exploration of interactions between complex carbohydrates and intrinsically disordered proteins.

Extending the enzymatic toolbox for heparosan polymerization, depolymerization, and detection.

Heparosan is an acidic polysaccharide expressed as a capsule polymer by pathogenic and commensal bacteria, e.g. by E.

A novel injectable radiopaque hydrogel with potent properties for multicolor CT imaging in the context of brain and cartilage regenerative therapy.

Cell therapy is promising to treat many conditions, including neurological and osteoarticular diseases. Encapsulation of cells within hydrogels facilitates cell delivery and can improve therapeutic effects. However, much work remains to be done to align treatment strategies with specific diseases.

Hyaluronan and Reactive Oxygen Species Signaling-Novel Cues from the Matrix?

Hyaluronan (HA) is a naturally occurring non-sulfated glycosaminoglycan (GAG) localized to the cell surface and the tissue extracellular matrix (ECM). It is composed of disaccharides containing glucuronic acid and N-acetylglucosamine, is synthesized by the HA synthase (HAS) enzymes and is degraded by hyaluronidase (HYAL) or reactive oxygen and nitrogen species (ROS/RNS) actions. HA is deposited as a high molecular weight (HMW) polymer and degraded to low molecular weight (LMW) fragments and oligosaccharides.

Arylidene Meldrum's Acid: A Versatile Structural Motif for the Design of Enzyme-Responsive "Covalent-Assembly" Fluorescent Probes with Tailor-Made Properties.

Latent cyclic carbon-centered nucleophiles (latent C-nucleophiles) are recently proving their value in the field of reaction-based fluorescent probes, far beyond their primary utility in organic synthesis. They are typically used to introduce a Michael acceptor moiety acting as a recognition/reaction site for analyte to be detected or as a kinetic promoter of fluorogenic cascade reactions triggered by a reactive species. C-nucleophiles bearing a further reactive handle offer an additional opportunity for tuning the physicochemical/targeting properties or providing drug-releasing capabilities to these probes, through the covalent attachment of ad hoc chemical moiety.

Copaiba Oil-Based Emulsion as a Natural Chemotherapeutic Agent for the Treatment of Bovine Mastitis: In Vivo Studies.

Copaiba oil-resin (COR) extracted from Ducke has been used as a natural chemotherapeutic agent for a wide range of therapeutic applications. This study presents an emulgel design with a high concentration of COR, designed to prevent and treat mastitis. The COR was stabilized in a gel matrix constituted by carbopol C934P and Pluronic F127 (ECO formulation) ratios.

Enzymatic Glyco-Modification of Synthetic Membrane Systems.

The present report assesses the capability of a soluble glycosyltransferase to modify glycolipids organized in two synthetic membrane systems that are attractive models to mimic cell membranes: giant unilamellar vesicles (GUVs) and supported lipid bilayers (SLBs). The objective was to synthesize the Gb3 antigen (Galα1,4Galβ1,4Glcβ-Cer), a cancer biomarker, at the surface of these membrane models. A soluble form of LgtC that adds a galactose residue from UDP-Gal to lactose-containing acceptors was selected.

Tailored hyaluronic acid-based nanogels as theranostic boron delivery systems for boron neutron cancer therapy.

Boron-rich nanocarriers possess great potential for advanced boron neutron capture therapy (BNCT) as an effective radiation treatment for invasive malignant tumors. If additionally, they can be imaged in a non-invasive and real-time manner allowing the assessment of local boron concentration, they could serve for dose calculation and image-guided BNCT to enhance tumor treatment efficacy. To meet this challenge, this study describes the design of a theranostic nanogel, enriched in B and fluorescent dye, to achieve selective imaging, and sufficient accumulation of boron at the tumor site.

Fabrication of Ultrafine, Highly Ordered Nanostructures Using Carbohydrate-Inorganic Hybrid Block Copolymers.

Block copolymers (BCPs) have garnered considerable interest due to their ability to form microphase-separated structures suitable for nanofabrication. For these applications, it is critical to achieve both sufficient etch selectivity and a small domain size. To meet both requirements concurrently, we propose the use of oligosaccharide and oligodimethylsiloxane as hydrophilic and etch-resistant hydrophobic inorganic blocks, respectively, to build up a novel BCP system, i.

Biodegradable Nanoparticles Loaded with Levodopa and Curcumin for Treatment of Parkinson's Disease.

Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the gold-standard drug available for treating PD. Curcumin has many pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, and antitumor properties.

Electrospun Azo-Cellulose Fabric: A Smart Polysaccharidic Photo-Actuator.

A natural polysaccharide-based smart photo-actuator is fabricated via electrospinning of cellulose 4-phenyl azobenzoate (Azo-Cel) from its organic solution in a mixture of high-volatile acetone, a poor solvent of Azo-Cel, and low-volatile N,N-dimethylacetamide (DMAc), a good solvent of Azo-Cel. At an optimal polymer concentration (17 wt%) and solvent mixing ratio (acetone/DMAc = 3/2 (v/v)), stable electrified polymer jets are formed and continuous nanofibers and their nonwoven fabric can be drawn on a cylinder-shaped rotating drum electrode under a high electric field (25 kV). Scanning electron microscopic observation of the Azo-Cel fabric confirms that the fabric consists of uniaxially aligned nanofibers with a mean diameter of 207 nm.

Three-dimensional structures, dynamics and calcium-mediated interactions of the exopolysaccharide, Infernan, produced by the deep-sea hydrothermal bacterium Alteromonas infernus.

The exopolysaccharide Infernan, from the bacterial strain GY785, has a complex repeating unit of nine monosaccharides established on a double-layer of sidechains. A cluster of uronic and sulfated monosaccharides confers to Infernan functional and biological activities. We characterized the 3-dimensional structures and dynamics along Molecular Dynamics trajectories and clustered the conformations in extended two-fold and five-fold helical structures.

Pillar[5]arene-Based Polycationic Glyco[2]rotaxanes Designed as Antibiofilm Agents.

(P.A.) is a human pathogen belonging to the top priorities for the discovery of new therapeutic solutions.

Exploring molecular determinants of polysaccharide lyase family 6-1 enzyme activity.

The polysaccharide lyase family 6 (PL6) represents one of the 41 polysaccharide lyase families classified in the CAZy database with the vast majority of its members being alginate lyases grouped into three subfamilies, PL6_1-3. To decipher the mode of recognition and action of the enzymes belonging to subfamily PL6_1, we solved the crystal structures of Pedsa0632, Patl3640, Pedsa3628 and Pedsa3807, which all show different substrate specificities and mode of action (endo-/exolyase). Thorough exploration of the structures of Pedsa0632 and Patl3640 in complex with their substrates as well as docking experiments confirms that the conserved residues in subsites -1 to +3 of the catalytic site form a common platform that can accommodate various types of alginate in a very similar manner but with a series of original adaptations bringing them their specificities of action.

Biophysical analysis of the plant-specific GIPC sphingolipids reveals multiple modes of membrane regulation.

The plant plasma membrane (PM) is an essential barrier between the cell and the external environment, controlling signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols, and phospholipids. The glycosyl inositol phosphoryl ceramides (GIPCs), representing up to 40% of total sphingolipids, are assumed to be almost exclusively in the outer leaflet of the PM.

Structure of the Polysaccharide Secreted by CNCM I-5035 (Epidermist 4.0).

(CNCM I-5035) secretes an exopolysaccharide used as ingredient in cosmetic industry under the trademark Epidermist 4.0. It is appreciated for its ability to improve the physical and chemical barrier functions of the skin by notably increasing the keratinocyte differentiation and epidermal renewal.

Reinforced macromolecular micelle-crosslinked hyaluronate gels induced by water/DMSO binary solvent.

Introducing macromolecular micelles into a biocompatible hyaluronic acid (HA) hydrogel is a promising strategy to improve its mechanical properties for biomedical applications. However, it is still unclear whether the solvent nature has an influence on the structure and property of HA gels especially when they are used for those cases containing binary solvents because reversible hydrophobic association within micelles could be weakened or even dissociated by organic solvents. In this work, we demonstrated that a binary solvent consisting of water and low-toxic dimethyl sulfoxide (DMSO), a commonly used cryoprotectant agent in biomedicine, can enhance the mechanical properties of hydrophobic-associated methacrylated hyaluronate (MeHA) gels crosslinked by diacrylated PEO99-PPO65-PEO99 (F127DA) macromolecular micelles, namely FH gels.

Boronate-ester crosslinked hyaluronic acid hydrogels for dihydrocaffeic acid delivery and fibroblasts protection against UVB irradiation.

Herein, we exploit the dynamic nature and pH dependence of complexes between phenylboronic acid and diol-containing molecules to control the release of an anti-photoaging agent, dihydrocaffeic acid (DHCA), from a dynamic covalent hydrogel (HG). The HG is prepared by reversible formation of boronate ester crosslinks between hyaluronic acid (HA) modified with saccharide (GLU) residues and HA functionalized with 3-aminophenylboronic acid (APBA), part of which is involved in complexation with DHCA. The hydrogel exhibited increased dynamic moduli and a lower relaxation time at pH 7.

Unraveling the complex enzymatic machinery making a key galactolipid in chloroplast membrane: a multiscale computer simulation.

Chloroplast membranes have a high content of the uncharged galactolipids monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). These galactolipids are essential for the biogenesis of plastids and functioning of the photosynthetic machinery. A monotopic glycosyltransferase, monogalactosyldiacylglycerol synthase synthesizes the bulk of MGDG.

Small-Angle Neutron Scattering Reveals the Structural Details of Thermosensitive Polymer-Grafted Cellulose Nanocrystal Suspensions.

Thanks to the use of small-angle neutron scattering (SANS), a detailed structural description of thermosensitive polymer-grafted cellulose nanocrystals (CNCs) was obtained and the behavior of aqueous suspensions of these derivatized biosourced particles upon temperature increase was revealed. Although literature data show that the surface grafting of thermosensitive polymers drastically enhances the colloidal properties of CNCs, direct space microscopic investigation techniques fail in providing sufficient structural information on these objects. In the case of CNCs decorated with temperature-sensitive polyetheramines following a peptide coupling reaction, a qualitative and quantitative analysis of SANS spectra shows that CNCs are homogeneously covered by a shell comprising polymer chains in a Gaussian conformation with a thickness equal to their radius of gyration in solution, thus revealing a mushroom regime.

Hydrogel-Colloid Composite Bioinks for Targeted Tissue-Printing.

The development of extrusion-based bioprinting for tissue engineering is conditioned by the design of bioinks displaying adequate printability, shape stability, and postprinting bioactivity. In this context, simple bioink formulations, made of cells supported by a polymer matrix, often lack the necessary versatility. To address this issue, intense research work has been focused on introducing colloidal particles into the ink formulation.

Improving the Performance and Stability of Perovskite Light-Emitting Diodes by a Polymeric Nanothick Interlayer-Assisted Grain Control Process.

CsPbBr is a promising light-emitting material due to its wet solution processability, high photoluminescence quantum yield (PLQY), narrow color spectrum, and cost-effectiveness. Despite such advantages, the morphological defects, unsatisfactory carrier injection, and stability issues retard its widespread applications in light-emitting devices (LEDs). In this work, we demonstrated a facile and cost-effective method to improve the morphology, efficiency, and stability of the CsPbBr emissive layer using a dual polymeric encapsulation governed by an interface-assisted grain control process (IAGCP).