Solid-state synthesis of a MOF/polymer composite for hydrodeoxygenation of vanillin.

A new solid-state method was used to introduce a furan-thiourea polymer into the pores of a MOF, Cr-BDC. Next, the activity of the new MOF-polymer composite containing Pd was assessed in the catalytic hydrodeoxygenation of vanillin, a biomass derived chemical.

Carbon nanotube uptake in cyanobacteria for near-infrared imaging and enhanced bioelectricity generation in living photovoltaics.

The distinctive properties of single-walled carbon nanotubes (SWCNTs) have inspired the development of many novel applications in the field of cell nanobiotechnology. However, studies thus far have not explored the effect of SWCNT functionalization on transport across the cell walls of prokaryotes. We explore the uptake of SWCNTs in Gram-negative cyanobacteria and demonstrate a passive length-dependent and selective internalization of SWCNTs decorated with positively charged biomolecules.

Unblocking Ion-occluded Pore Channels in Poly(triazine imide) Framework for Proton Conduction.

Poly(triazine imide) or PTI is an ordered graphitic carbon nitride hosting Å-scale pores attractive for selective molecular transport. AA'-stacked PTI layers are synthesized by ionothermal route during which ions occupy the framework and occlude the pores. Synthesis of ion-free PTI hosting AB-stacked layers has been reported, however, pores in this configuration are blocked by the neighboring layer.

High-Throughput Sizing, Counting, and Elemental Analysis of Anisotropic Multimetallic Nanoparticles with Single-Particle Inductively Coupled Plasma Mass Spectrometry.

Nanoparticles (NPs) have wide applications in physical and chemical processes, and their individual properties (e.g., shape, size, and composition) and ensemble properties (e.

Copper Phosphonate Lamella Intermediates Control the Shape of Colloidal Copper Nanocrystals.

Understanding the structure and behavior of intermediates in chemical reactions is the key to developing greater control over the reaction outcome. This principle is particularly important in the synthesis of metal nanocrystals (NCs), where the reduction, nucleation, and growth of the reaction intermediates will determine the final size and shape of the product. The shape of metal NCs plays a major role in determining their catalytic, photochemical, and electronic properties and, thus, the potential applications of the material.

Sustainable polyesters via direct functionalization of lignocellulosic sugars.

The development of sustainable plastics from abundant renewable feedstocks has been limited by the complexity and efficiency of their production, as well as their lack of competitive material properties. Here we demonstrate the direct transformation of the hemicellulosic fraction of non-edible biomass into a tricyclic diester plastic precursor at 83% yield (95% from commercial xylose) during integrated plant fractionation with glyoxylic acid. Melt polycondensation of the resulting diester with a range of aliphatic diols led to amorphous polyesters (M = 30-60 kDa) with high glass transition temperatures (72-100 °C), tough mechanical properties (ultimate tensile strengths of 63-77 MPa, tensile moduli of 2,000-2,500 MPa and elongations at break of 50-80%) and strong gas barriers (oxygen transmission rates (100 µm) of 11-24 cc m day bar and water vapour transmission rates (100 µm) of 25-36 g m day) that could be processed by injection moulding, thermoforming, twin-screw extrusion and three-dimensional printing.

Live-Cell Fluorescence Lifetime Multiplexing Using Synthetic Fluorescent Probes.

Fluorescence lifetime multiplexing requires fluorescent probes with distinct fluorescence lifetimes but similar spectral properties. Even though synthetic probes for many cellular targets are available for multicolor live-cell fluorescence microscopy, few of them have been characterized for their use in fluorescence lifetime multiplexing. Here, we demonstrate that, from a panel of 18 synthetic probes, eight pairwise combinations are suitable for fluorescence lifetime multiplexing in living mammalian cell lines.

1,3,2-Diazaphospholene-Catalyzed Reductive Cyclizations of Organohalides.

1,3,2-diazaphospholenes hydrides (DAP-Hs) are highly nucleophilic organic hydrides serving as main-group catalysts for a range of attractive transformations. DAP hydrides can act as stoichiometric hydrogen atom transfer agents in radical reactions. Herein, we report a DAP-catalyzed reductive radical cyclization of a broad range of aryl and alkyl halides under mild conditions.

Heteroatom oxidation controls singlet-triplet energy splitting in singlet fission building blocks.

Singlet fission (SF) is a promising multiexciton-generating process. Its demanding energy splitting criterion - that the S energy must be at least twice that of T - has limited the range of materials capable of SF. We propose heteroatom oxidation as a robust strategy to achieve sufficient S/T splitting, and demonstrate the potential of this approach for intramolecular SF.

Engineered HaloTag variants for fluorescence lifetime multiplexing.

Self-labeling protein tags such as HaloTag are powerful tools that can label fusion proteins with synthetic fluorophores for use in fluorescence microscopy. Here we introduce HaloTag variants with either increased or decreased brightness and fluorescence lifetime compared with HaloTag7 when labeled with rhodamines. Combining these HaloTag variants enabled live-cell fluorescence lifetime multiplexing of three cellular targets in one spectral channel using a single fluorophore and the generation of a fluorescence lifetime-based biosensor.

Investigating active phase loss from supported ruthenium catalysts during supercritical water gasification.

Active phase loss mechanisms from Ru/AC catalysts were studied in continuous supercritical water gasification (SCWG) for the first time by analysing the Ru content in process water with low limit-of-detection time-resolved ICP-MS. Ru loss was investigated alongside the activity of commercial and in-house Ru-based catalysts, showing very low Ru loss rates compared to Ru/metal-oxides (0.2-1.

Branched Poly(Aryl Piperidinium) Membranes for Anion-Exchange Membrane Fuel Cells.

Anion-exchange membrane fuel cells (AEMFCs) are a promising, next-generation fuel cell technology. AEMFCs require highly conductive and robust anion-exchange membranes (AEMs), which are challenging to develop due to the tradeoff between conductivity and water uptake. Here we report a method to prepare high-molecular-weight branched poly(aryl piperidinium) AEMs.

Hybridization of Synthetic Humins with a Metal-Organic Framework for Precious Metal Recovery and Reuse.

The number of synthetic strategies used to functionalize MOFs with polymers is rapidly growing; this stems from the knowledge that non-native polymeric guests can significantly boost MOF performance in a number of desirable applications. The current work presents a scalable and solid-state method for MOF/polymer composite production. This simple method constitutes mixing a MOF powder, namely, Fe-BTC (BTC = 1,3,5-benzenetricarboxylate), with a biomass-derived solid monomer, 5-hydroxymethylfurfural (HMF), and subsequently heating the solids; the latter promotes both solid-state diffusion of HMF into the MOF and the formation of polymeric humin species with a high density of accessible hydroxyl functionality within the MOF pore.

Crossed Regio- and Enantioselective Iron-Catalyzed [4+2]-Cycloadditions of Unactivated Dienes.

The cyclohexene motif is ubiquitous in nature and specialty chemicals. A straightforward selective access to chiral cyclohexenes from unactivated dienes and dienophiles is not feasible by classical Diels-Alder reaction and constitutes an unsolved synthetic challenge. We report a mild and enantioselective iron-catalyzed cross-[4+2]-cycloaddition of unactivated dienes providing access to chiral 1,3-substituted vinyl-cyclohexenes.

Proteome-wide analysis of protein lipidation using chemical probes: in-gel fluorescence visualization, identification and quantification of N-myristoylation, N- and S-acylation, O-cholesterylation, S-farnesylation and S-geranylgeranylation.

Protein lipidation is one of the most widespread post-translational modifications (PTMs) found in nature, regulating protein function, structure and subcellular localization. Lipid transferases and their substrate proteins are also attracting increasing interest as drug targets because of their dysregulation in many disease states. However, the inherent hydrophobicity and potential dynamic nature of lipid modifications makes them notoriously challenging to detect by many analytical methods.

Multiplexed Single-Molecule Experiments Reveal Nucleosome Invasion Dynamics of the Cas9 Genome Editor.

Single-molecule measurements provide detailed mechanistic insights into molecular processes, for example in genome regulation where DNA access is controlled by nucleosomes and the chromatin machinery. However, real-time single-molecule observations of nuclear factors acting on defined chromatin substrates are challenging to perform quantitatively and reproducibly. Here we present XSCAN (multipleed ingle-molecule detection of hromatin ssociatio), a method to parallelize single-molecule experiments by simultaneous imaging of a nucleosome library, where each nucleosome type carries an identifiable DNA sequence within its nucleosomal DNA.

SUV39 SET domains mediate crosstalk of heterochromatic histone marks.

The SUV39 class of methyltransferase enzymes deposits histone H3 lysine 9 di- and trimethylation (H3K9me2/3), the hallmark of constitutive heterochromatin. How these enzymes are regulated to mark specific genomic regions as heterochromatic is poorly understood. Clr4 is the sole H3K9me2/3 methyltransferase in the fission yeast and recent evidence suggests that ubiquitination of lysine 14 on histone H3 (H3K14ub) plays a key role in H3K9 methylation.

Atropo-Enantioselective Oxidation-Enabled Iridium(III)-Catalyzed C-H Arylations with Aryl Boronic Esters.

Atropo-enantioselective biaryl coupling through C-H bond functionalization is an emerging technology allowing direct construction of axially chiral molecules. This approach is largely limited to electrophilic coupling partners. We report a highly atropo-enantioselective C-H arylation of tetralone derivatives paired with aryl boronic esters as nucleophilic components.

Metal-ligand bond strength determines the fate of organic ligands on the catalyst surface during the electrochemical CO reduction reaction.

Colloidally synthesised nanocrystals (NCs) are increasingly utilised as catalysts to drive both thermal and electrocatalytic reactions. Their well-defined size and shape, controlled by organic ligands, are ideal to identify the parameters relevant to the activity, selectivity and stability in catalysis. However, the impact of the native surface ligands during catalysis still remains poorly understood, as does their fate.

NICEpath: Finding metabolic pathways in large networks through atom-conserving substrate-product pairs.

Motivation: Finding biosynthetic pathways is essential for metabolic engineering of organisms to produce chemicals, biodegradation prediction of pollutants and drugs, and for the elucidation of bioproduction pathways of secondary metabolites. A key step in biosynthetic pathway design is the extraction of novel metabolic pathways from big networks that integrate known biological, as well as novel, predicted biotransformations. However, the efficient analysis and the navigation of big biochemical networks remain a challenge.

Portable bioluminescent platform for in vivo monitoring of biological processes in non-transgenic animals.

Bioluminescent imaging (BLI) is one of the most powerful and widely used preclinical imaging modalities. However, the current technology relies on the use of transgenic luciferase-expressing cells and animals and therefore can only be applied to a limited number of existing animal models of human disease. Here, we report the development of a "portable bioluminescent" (PBL) technology that overcomes most of the major limitations of traditional BLI.

Hydrogen Storage by Reduction of CO₂ to Synthetic Hydrocarbons.

The storage of renewable energy is crucial for the substitution of fossil fuels with renewable energy. Hydrogen is the first step in the conversion of electricity from renewable sources to an energy carrier. However, hydrogen is technically and economically challenging to store, but can be converted with CO₂ from the atmosphere or oceans to hydrocarbons.

Asymmetric opening of the homopentameric 5-HT serotonin receptor in lipid bilayers.

Pentameric ligand-gated ion channels (pLGICs) of the Cys-loop receptor family are key players in fast signal transduction throughout the nervous system. They have been shown to be modulated by the lipid environment, however the underlying mechanism is not well understood. We report three structures of the Cys-loop 5-HT serotonin receptor (5HTR) reconstituted into saposin-based lipid bilayer discs: a symmetric and an asymmetric apo state, and an asymmetric agonist-bound state.

Noninvasive imaging and quantification of bile salt hydrolase activity: From bacteria to humans.

The microbiome-produced enzyme bile salt hydrolase (BSH) plays a central role in human health, but its function remains unclear due to the lack of suitable methods for measuring its activity. Here, we have developed a novel optical tool based on ultrasensitive bioluminescent imaging and demonstrated that this assay can be used for quick and cost-effective quantification of BSH activity across a broad range of biological settings including pure enzymes and bacteria, intact fecal slurries, and noninvasive imaging in live animals, as well as for the assessment of BSH activity in the entire gastrointestinal tract of mice and humans. Using this assay, we showed that certain types of prebiotics are capable of increasing BSH activity of the gut microbiota in vivo and successfully demonstrated potential application of this assay as a noninvasive diagnostic test to predict the clinical status of inflammatory bowel disease (IBD) patients.