Microcrystal electron diffraction (MicroED) is an electron cryo-microscopy (cryo-EM) technique able to produce high-resolution protein structures from nanocrystalline and microcrystalline material. Employing smaller crystals can improve ligand soaking to reveal new protein-ligand complexes with future potentials in drug discovery. See Clark et al.

Phototherapeutics are an attractive approach towards targeted therapies. The ability to uncage drugs in localised sites through light activation could enable controlled dosing and reduced side effects. See Vickerman et al.

The bottom-up assembly of an artificial cell would enable the study of minimal systems. Membranes — formed by the self-assembly of lipids — are considered an essential cellular subsystem. The synthesis of these membranes is thus an essential step in understanding the transition from non-living chemistry to biology. See Podolsky et al.

Electron diffraction allows us to determine molecular structures from sub-micrometre-sized crystals with similar precision as X-ray diffraction does with bigger crystals. The burgeoning recent applications of electron diffraction suggest that it can readily be included in the analytical portfolio of chemists and those in related disciplines. See Gruene et al.

Late-stage functionalizations offer a rapid route to structure diversification and library generation and are thus particularly attractive within medicinal chemistry campaigns. They provide access to new structures both for SAR exploration as well as for studies of drug mechanism as well as metabolism. These functionalizations exploit both innate and directed reactivity and their development has drawn heavily on recent research into new reaction manifolds such as biocatalysis and electrosynthesis. See Guillemard et al.

In just over a decade, radical-pairing interactions have developed from rarely observed curiosity into a major tool for the supramolecular chemistry. The ease with which radical species can be prepared using redox stimulation enables their application in the assembly and control of elaborate mechanically-interlocked structures such as the 3-fold symmetric cyclic daisy chain structure pictured. See Cai, Zhang, Astumian and Stoddart.

The next global threat, may be a pollutant, a chemical toxin or a biohazard, and it may result from natural disaster or intentional misuse. It is especially important that we aim to protect those who put themselves in harm’s way to protect and caring for the safety of others. Chemistry can play its part through the development of surface coatings and functionalized fabrics that can inactivate or neutralize biological and chemical toxins. See Jabbour, Parker, Hutter & Weckhuysen.

A ‘reversible’ catalyst allows a reaction to proceed rapidly even at small departures from equilibrium. These fast and energy-efficient transformations are part of a relatively smooth potential energy landscape that can feature in synthetic and biological systems alike. See Fourmond, Plumeré & Léger.

Nanostructures built from DNA are being applied in biosensing, cell modulation, bioimaging and drug delivery. But the sensitivity of these structures to nucleases present in the physiological environment is an impediment. Strategies that increase the nuclease resistance of DNA nanostructures while retaining their functions are thus of great interest as are methods to evaluate resistance and quantify stability. See Chandrasekaran.

Mechanical loads can affect chemical reactivity in diverse ways. Exerting pressure on fullerenes in a ball mill sees them dimerize and trimerize, while pulling on opposite ends of a biimidazole causes it to rupture into two radicals. Tension can also break bonds away from the main chain of a molecule, as in the case of phosphate esters. See O’Neil and Boulatov

Bispecific antibodies have traditionally been generated by protein engineering, but recently, following developments in the field of site-selective protein modification and bioorthogonal click chemistry, new and improved chemical methods have begun to emerge. These methods offer advantages, including fast reaction times, modularity and the possible attachment of multiple additional cargo, such as dyes and drugs, to the construct. See Szijj & Chudasama

The bioluminescent Lampyris beetles communicate with one other by making an excited light-emitting molecule called oxyluciferin, pictured here in one of its many protonation/tautomeric states. Generated by luciferase enzymes, oxyluciferin is common to many different animals that somehow each emit different colours. Thus, subtle structural differences in luciferases between species dictate the colours by which they communicate. See Carrasco-López et al.