Yangcorbett9369

The preparation of chondroitin sulfate (CS) oligosaccharide mimetics, more easily synthesized than natural sequences, is a highly interesting task because these compounds pave the way for modulation of the biological processes in which CS is involved. Herein, we report the synthesis of CS type E analogues which present easily accessible glucose units instead of glucuronic acid (GlcA) moieties. NMR experiments and molecular dynamics simulations showed that the 3D structure of these compounds is similar to the structure of the natural CS-E oligosaccharides. In addition, fluorescence polarization (FP) and saturation transfer difference NMR (STD-NMR) experiments revealed that the synthesized CS-like derivatives were able to interact with midkine, a model heparin-binding growth factor, suggesting that the presence of the GlcA carboxylate groups is not essential for the binding. Overall, our results indicate that the synthesized glucose-containing oligosaccharides can be considered as functional and structural CS mimetics.Colloidal protein-protein interactions (PPIs) of attractive and repulsive nature modulate the solubility of proteins, their aggregation, precipitation and crystallization. Such interactions are very important for many biotechnological processes, but are complex and hard to control, therefore, difficult to be understood in terms of measurements alone. In diluted protein solutions, PPIs can be estimated from the osmotic second virial coefficient, B22, which has been calculated using different methods and levels of theory. The most popular approach is based on the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and its extended versions, i.e. xDLVO. Despite much efforts, these models are not fully quantitative and must be fitted to experiments, which limits their predictive value. Here, we report an extended xDLVO-CG model, which extends existing models by a coarse-grained representation of proteins and the inclusion of an additional ion-protein dispersion interaction term. We demonstrate for four proteins, i.e. lysozyme (LYZ), subtilisin (Subs), bovine serum albumin (BSA) and immunoglobulin (IgG1), that semi-quantitative agreement with experimental values without the need to fit to experimental B22 values. While most likely not the final step in the nearly hundred years of research in PPIs, xDLVO-CG is a step towards predictive PPIs calculations that are transferable to different proteins.Cellular tissue behavior is a multiscale problem. At the cell level, out of equilibrium, biochemical reactions drive physical cell-cell interactions in a typical active matter process. Cell modeling computer simulations are a robust tool to explore countless possibilities and test hypotheses. Here, we introduce a two-dimensional, extended active matter model for biological cells. A ring of interconnected self-propelled particles represents the cell. Neighboring particles are subject to harmonic and bending potentials. Within a characteristic time, each particle's self-velocity tends to align with its scattering velocity after an interaction. Translational modes, rotational modes, and mixtures of these appear as collective states. Using analytical results derived from active Brownian particles, we identify effective characteristic time scales for ballistic and diffusive movements. Finite-size scale investigation shows that the ring diffusion increases linearly with its size when in collective movement. A study on the ring shape reveals that all collective states are present even when bending forces are weak. In that case, when in a translational mode, the collective velocity aligns with the largest ring's direction in a spontaneous polarization emergence.Hydrogels are perfectly suited to support cell and tissue growth in advanced tissue engineering applications as well as classical wound treatment scenarios. Ideal hydrogel materials for these applications should be easy to produce, biocompatible, resorbable and antimicrobial. Here we report the fabrication of degradable covalent antimicrobial lysine and tryptophan containing copolypeptide hydrogels, whereby the hydrogel properties can be independently modulated by the copolypeptide monomer ratio and chiral composition. Well-defined statistical copolypeptides comprising different overall molecular weights as well as ratios of l- and d-lysine and tryptophan at ratios of 35  15, 70  30 and 80  20 were obtained by N-carboxyanhydride (NCA) polymerisation and subsequently crosslinked by the selective reaction of bifunctional triazolinedione (TAD) with tryptophan. Real-time rheology was used to monitor the crosslinking reaction recording the fastest increase and overall modulus for copolypeptides with the higher tryptophan ratio. Water uptake of cylindrical hydrogel samples was dependent on crosslinking ratio but found independent of chiral composition, while enzymatic degradation proceeded significantly faster for samples containing more l-amino acids. Antimicrobial activity on a range of hydrogels containing different polypeptide chain lengths, lysine/tryptophan composition and l/d enantiomers was tested against reference laboratory strains of Gram-negative Escherichia coli (E. learn more coli; ATCC25922) and Gram-positive, Staphylococcus aureus (S. aureus; ATCC25923). log reductions of 2.8-3.4 were recorded for the most potent hydrogels. In vitro leachable cytotoxicity tests confirmed non-cytotoxicity as per ISO guidelines.A site-selective direct arylation reaction of carbazole and other N-heterocycles with diazo-naphthalen-2(1H)-ones has been developed. While Au(i)-NHC catalysts lead to selective C3-arylation, palladium acetate allows for selective N-H arylation, displaying complete site-selectivity each. To show the applicability of these arylation reactions, one-pot, two-fold diarylation reactions of carbazole were demonstrated.Chemical looping combustion (CLC) technology is an innovative energy conversion technology that employs oxygen carriers (OC), typically metal oxides, to burn fossil fuels with a minimal carbon footprint. The performance of OCs can be enhanced by the support on which they are deposited through two mechanisms acting at different scales, viz., microstructural and synergetic effects. In this work, the synergetic effect of NiO supported on TiO2 in reaction with hydrogen as a fuel is studied using density functional theory (DFT). Changes in the energetics of the NiO-hydrogen reaction are explained as a consequence of the interaction between the TiO2 support and NiO. The results indicate that the electronic interaction of the TiO2 support with NiO lowers the energy of intermediate states and the energy of the reaction. The effect of TiO2 increases with the creation of more O vacancies as the reaction proceeded. This enhanced reactivity of the NiO-hydrogen reaction is attributed to both an electronic effect of TiO2 and a geometric effect due to O vacancy creation.