Research articles

Helical structures play important roles in biological processes, yet their aggregation into fibres—which can in turn form gels—is poorly understood. Now, the self-assembly of a linear pentakis (urea) peptidomimetic compound into helices that further intertwine into well-defined braided structures has been described and analysed through braid theory. Homochiral gels may be formed by exposing the precursor sol to a chiral material.

Biosynthesis of peptidoglycan requires carefully orchestrated transpeptidation reactions to maintain the structural integrity of this essential component of the bacterial cell wall. Now, rotor-fluorescent d-amino acids have been shown to enable real-time tracking of these transpeptidation reactions in live bacterial cells. These powerful tools allow visualization of peptidoglycan biosynthesis with high spatiotemporal resolution.

An automated platform that can synthesize a wide range of complex glycans could greatly facilitate progress in glycoscience. Now, a fully automated process for enzyme-mediated oligosaccharide synthesis has been developed. This process uses glycosyltransferase-catalysed reactions performed in solution, with product purification being accomplished by solid phase extraction using a sulfonate tag.

Amphiphilic self-assembly is ubiquitous both in nature and synthetic systems, yet the underlying mechanisms governing the transition from molecules to assemblies have not yet been fully resolved. Now, the role of liquid–liquid phase separation prior to the assembly process has been explored through the detailed analysis of a model block-copolymer system.

A concise strategy for engineering functional, supramolecular protein complexes has now been developed based on single-mutation-mediated covalent tethering. Metalloproteins designed with this method can sustain large alterations to the metal coordination environment, bind small molecules, exhibit reversible redox activity and sustain large alterations to the protein structure.

Single-molecule force spectroscopy reveals that maleimide–thiol adducts can be stabilized by stretching through a force-dependent kinetic control mechanism. This unconventional use of mechanochemistry enabled us to produce stable polymer–protein conjugates by simply applying a mechanical force to the maleimide–thiol adducts through mild ultrasonication.

Heterometallic clusters have shown promise in catalysis and small-molecule activation, but species comprising uranium–metal bonds have remained difficult to synthesize. Now, facile reactions between uranium and nickel precursors have led to nickel-bridged diuranium clusters supported by a heptadentate N₄P₃ scaffold. Computational analysis points to an unusual electronic configuration for uranium, U(iii)-5f²6d¹.

Conjugated mesopolymers can combine the advantages of polymers and oligomers, but have received less attention as semiconducting materials. Now, such compounds have been synthesized by direct arylation polycondensation that exhibit high molecular regularity, solubility and solution processability. These mesopolymers also show electron mobilities that are significantly better than those of their polymer counterparts.

A two-coordinate monovalent gold complex that features a highly polarized aluminium–gold covalent bond, Al^δ+–Au^δ−, has been synthesized using a very strongly electron-donating aluminyl ligand. In solution, the complex reacts as a nucleophilic source of gold towards heteroallenes such as carbodiimides and CO₂.

Developing a stable metallic lithium anode is necessary for next-generation batteries; however, lithium is prone to corrosion, a process that must be better understood if practical devices are to be created. A Kirkendall-type mechanism of lithium corrosion has now been observed. The corrosion is fast and is governed by a galvanic process.

One-dimensional diffusive binding represents an important mechanism used by nature to facilitate many fundamental biochemical processes. Now, a completely synthetic system with similar capabilities has been constructed. The system was exploited to significantly speed up bimolecular reactions and to catalytically transport molecular cargo in solution and within physically separated compartments.

Anchored single-atom catalysts have recently been shown to be very active for various processes, however, a catalyst that features two adjacent copper atoms—which we call an atom-pair catalyst—is now reported. The Cu₁⁰–Cu₁^x+ pair structures work together to carry out the critical bimolecular step in CO₂ reduction.

Despite their huge potential in medicinal chemistry, current approaches for the synthesis of fluorinated piperidines are often impractical. A straightforward process for the rhodium-catalysed dearomatization–hydrogenation of fluoropyridines has now been described. This strategy enables the highly diastereoselective formation of a variety of all-cis-(multi)fluorinated piperidines and the study of their conformational behaviour.

Symmetrical protein oligomers perform key structural and catalytic functions in nature, but engineering such oligomers synthetically is challenging. Now, oppositely supercharged synthetic variants of normally monomeric proteins have been shown to assemble via specific, introduced electrostatic contacts into symmetrical, highly well-defined oligomers.