Covalent Template-Directed Synthesis: A Powerful Tool for the Construction of Complex Molecules.

Template-directed synthesis has become a powerful methodology to access complex molecules. Noncovalent templating has been widely used in the last few decades, but less attention has been paid to covalent template-directed synthesis, despite the fact that this methodology was used for the first reported synthesis of a catenane. This review highlights the evolution of covalent templating over the last 60 years, thereby providing a toolbox for the design of efficient covalent templating processes.

Substituent Effects on Cooperativity in Three-Component H-Bond Networks Involving Phenol-Phenol Interactions.

Cooperativity between H-bonding interactions in networks is a fundamental aspect of solvation and self-assembly in molecular systems. The interaction of a series of bisphenols, which make an intramolecular H-bond between the two hydroxyl groups, and quinuclidine was used to quantify cooperativity in three-component networks. The presence of the intramolecular H-bond in the bisphenols was established by using H NMR spectroscopy in solution and X-ray crystallography in the solid state.

Sequence-selective pulldown of recognition-encoded melamine oligomers using covalent capture on a solid support.

The covalent capture of recognition-encoded melamine oligomers (REMO) with a target attached to a solid support was investigated. Sequence-selective pulldown of complementary oligomers was observed when the target was challenged with a randomised library of oligomers. The approach provides an affinity selection method for the discovery of functional REMO sequences.

Length and Sequence-Selective Polymer Synthesis Templated by a Combination of Covalent and Noncovalent Base-Pairing Interactions.

Information can be encoded and stored in sequences of monomer units organized in linear synthetic polymers. Replication of sequence information is of fundamental importance in biology; however, it represents a challenge for synthetic polymer chemistry. A combination of covalent and noncovalent base pairs has been used to achieve high-fidelity templated synthesis of synthetic polymers that encode information as a sequence of different side-chain recognition units.

Solvation-Enhanced Salt Bridges.

Salt bridges formed by amidines and carboxylic acids represent an important class of noncovalent interaction in biomolecular and supramolecular systems. Isothermal titration calorimetry was used to study the relationships between the strength of the interaction, the chemical structures of the components, and the nature of the solvent. The stability of the 1:1 complex formed in chloroform changed by 2 orders of magnitude depending on the basicity of the amidine and the acidity of the acid, which is consistent with proton transfer in the complex.

Polarisation effects on the H-bond acceptor properties of sulfonamides.

The strengths of H-bonding interactions in networks are affected by cooperativity between the interacting sites. Compounds with an intramolecular H-bond between a sulfonamide NH group and pyridine nitrogen were used to measure the magnitude of cooperative effects on intermolecular H-bonding interactions with the sulfonamide oxygen. X-ray crystallography and H NMR experiments confirm the presence of the intramolecular H-bond and show that it is maintained in the 1 : 1 complex formed with perfluoro--butanol (PFTB) in -octane solution.

Musketeer: a software tool for the analysis of titration data.

Musketeer is a powerful open-source software tool for the analysis of titration data, featuring a simple cross-platform graphical interface for importing data directly from UV-vis, fluorescence and NMR spectrometers, or from spreadsheets. The fast data analysis algorithm can be used to obtain equilibrium constants for simple binding isotherms, as well as for more complicated systems with multiple competing equilibria. Applications of Musketeer for the analysis of a range of different supramolecular and biomolecular systems are illustrated, including titrations with multiple spectroscopically active species, competitive binding assays, denaturation experiments, optimisation of concentrations as variables.

Negative cooperativity in the formation of H-bond networks involving primary anilines.

Networks of H-bonds can show non-additive behaviour, where the strength of one interaction perturbs another. The magnitude of such cooperative effects can be quantified by measuring the effect of the presence of an intramolecular H-bond at one site on a molecule on the association constant for formation of an intermolecular H-bond at another site. This approach has been used to quantify the cooperativity associated with the interaction of a primary amine with two H-bond acceptors.

Single-cell multi-omic and spatial profiling of human kidneys implicates the fibrotic microenvironment in kidney disease progression.

Kidneys are intricate three-dimensional structures in the body, yet the spatial and molecular principles of kidney health and disease remain inadequately understood. We generated high-quality datasets for 81 samples, including single-cell, single-nuclear, spot-level (Visium) and single-cell resolution (CosMx) spatial-RNA expression and single-nuclear open chromatin, capturing cells from healthy, diabetic and hypertensive diseased human kidneys. Combining these data, we identify cell types and map them to their locations within the tissue.

impacts epithelial turnover and is resistant to induced death of the host cell.

Unlabelled: Infection with the apicomplexan parasite is a leading cause of diarrheal disease. Cryptosporidiosis is of particular importance in infants and shows a strong association with malnutrition, both as a risk factor and as a consequence. invades and replicates within the small intestine epithelial cells.

Intestinal cDC1s provide cues required for CD4+ T cell-mediated resistance to Cryptosporidium.

Cryptosporidium is an enteric pathogen and a prominent cause of diarrheal disease worldwide. Control of Cryptosporidium requires CD4+ T cells, but how protective CD4+ T cell responses are generated is poorly understood. Here, Cryptosporidium parasites that express MHCII-restricted model antigens were generated to understand the basis for CD4+ T cell priming and effector function.

Development of a nucleoside-modified mRNA vaccine against clade 2.3.4.4b H5 highly pathogenic avian influenza virus.

mRNA lipid nanoparticle (LNP) vaccines would be useful during an influenza virus pandemic since they can be produced rapidly and do not require the generation of egg-adapted vaccine seed stocks. Highly pathogenic avian influenza viruses from H5 clade 2.3.

Analysis of intestinal epithelial cell responses to Cryptosporidium highlights the temporal effects of IFN-γ on parasite restriction.

The production of IFN-γ is crucial for control of multiple enteric infections, but its impact on intestinal epithelial cells (IEC) is not well understood. Cryptosporidium parasites exclusively infect epithelial cells and the ability of interferons to activate the transcription factor STAT1 in IEC is required for parasite clearance. Here, the use of single cell RNA sequencing to profile IEC during infection revealed an increased proportion of mid-villus enterocytes during infection and induction of IFN-γ-dependent gene signatures that was comparable between uninfected and infected cells.

Ligand Profiling as a Diagnostic Tool to Differentiate Patient-Derived α-Synuclein Polymorphs.

Amyloid fibrils are characteristic of many neurodegenerative diseases, including Alzheimer's and Parkinson's diseases. While different diseases may have fibrils formed of the same protein, the supramolecular morphology of these fibrils is disease-specific. Here, a method is reported to distinguish eight morphologically distinct amyloid fibrils based on differences in ligand binding properties.

Efficient automated solid-phase synthesis of recognition-encoded melamine oligomers.

Recognition-encoded melamine oligomers (REMO) are synthetic polymers with an alternating 1,3,5-triazine-piperazine backbone and side chains equipped with either a phenol or phosphine oxide recognition unit. Here, we describe an automated method for highly efficient solid-phase synthesis (SPS) of REMO of any specified length and sequence. These SPS protocols are amongst the most robust reported to date, as demonstrated by the synthesis of a mixed-sequence 42-mer, which was obtained in excellent crude purity on a 100 mg scale.

Lipid Nanoparticle-Associated Inflammation is Triggered by Sensing of Endosomal Damage: Engineering Endosomal Escape Without Side Effects.

Lipid nanoparticles (LNPs) have emerged as the dominant platform for RNA delivery, based on their success in the COVID-19 vaccines and late-stage clinical studies in other indications. However, we and others have shown that LNPs induce severe inflammation, and massively aggravate pre-existing inflammation. Here, using structure-function screening of lipids and analyses of signaling pathways, we elucidate the mechanisms of LNP-associated inflammation and demonstrate solutions.

Selective Duplex Formation in Mixed Sequence Libraries of Synthetic Polymers.

Recognition-encoded melamine oligomers (REMO) are synthetic polymers that feature an alternating 1,3,5-triazine-piperazine backbone and side-chains equipped with either a phenol or phosphine oxide recognition unit. An automated method for the solid-phase synthesis (SPS) of REMO of any specified sequence has been developed starting from dichlorotriazine monomer building blocks. Complementary homo-oligomers with either six phenols or six phosphine oxides were synthesized and shown to form a stable duplex in nonpolar solvents by NMR denaturation experiments.

Endogenous IL-27 during toxoplasmosis limits early monocyte responses and their inflammatory activation by pathological T cells.

Unlabelled: Mice that lack the genes for IL-27, or the IL-27 receptor, and infected with develop T cell-mediated pathology. Here, studies were performed to determine the impact of endogenous IL-27 on the immune response to in wild-type (WT) mice. Analysis of infected mice revealed the early production of IL-27p28 by a subset of Ly6C, inflammatory monocytes, and sustained IL-27p28 production at sites of acute and chronic infection.

An atomic surface site interaction point description of non-covalent interactions.

Molecular electrostatic potential surfaces (MEPS) calculated using density functional theory have been used to develop a simplified description of the non-covalent interaction properties of organic molecules. The Atomic Interaction Point (AIP) model introduced here represents an evolution of the Surface Site Interaction Point (SSIP) model described previously, in which a molecule is represented by a discrete set of interaction points that define sites of interaction with other molecules. The interaction sites are described by interaction parameters that are equivalent to the experimentally determined H-bond donor and acceptor parameters and .

A closer look at amyloid ligands, and what they tell us about protein aggregates.

The accumulation of amyloid fibrils is characteristic of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease. Detecting these fibrils with fluorescent or radiolabelled ligands is one strategy for diagnosing and better understanding these diseases. A vast number of amyloid-binding ligands have been reported in the literature as a result.

Ligand Profiling to Characterize Different Polymorphic Forms of α-Synuclein Aggregates.

The presence of amyloid fibrils is a characteristic feature of many diseases, most famously neurodegenerative disease. The supramolecular structure of these fibrils appears to be disease-specific. Identifying the unique morphologies of amyloid fibrils could, therefore, form the basis of a diagnostic tool.

Replication of synthetic recognition-encoded oligomers by ligation of trimer building blocks.

The development of methods for replication of synthetic information oligomers will underpin the use of directed evolution to search new chemical space. Template-directed replication of triazole oligomers has been achieved using a covalent primer in conjunction with non-covalent binding of complementary building blocks. A phenol primer equipped with an alkyne was first attached to a benzoic recognition unit on a mixed sequence template selective covalent ester base-pair formation.

Analysis of intestinal epithelial cell responses to highlights the temporal effects of IFN-γ on parasite restriction.

The production of IFN-γ is crucial for control of multiple enteric infections, but its impact on intestinal epithelial cells (IEC) is not well understood. parasites exclusively infect epithelial cells and the ability of interferons to activate the transcription factor STAT1 in IEC is required for parasite clearance. The use of single cell RNA sequencing to profile IEC during infection revealed induction of IFN-γ-dependent gene signatures that was comparable between uninfected and infected cells, and IEC expression of the IFN-γ receptor was required for parasite control.