Crystal structure prediction: achievements and opportunities

This editorial gives gives an update on the current status of crystal structure prediction and its opportunities and challenges.

The dominant component of strong π-hole interactions: electrostatic attraction versus charge transfer

A long-asked question concerning the dominant component of strong π-hole interactions is addressed.

Comparison of the structure and activity of thio­redoxin 2 and thio­redoxin 1 from Acinetobacter baumannii

A 1.20 Å high-resolution structure of thio­redoxin 2 (Trx2) from Acinetobacter baumannii (abTrx2) is elucidated. Based on comparison of structure and activity with Trx1, it is revealed that the two Trxs in A. baumannii possess similar activity, although Trx2 contains an additional N-terminal zinc-finger domain and exhibits more flexible and dynamic properties in solution.

The nature of π-hole interactions between iodide anions and quinoid rings in the crystalline state

Analysis of charge density in a π-hole contact between an iodide anion and tetra­bromo­quinone reveals the nature of the interaction as dominantly electrostatic with a significant dispersion component. The quinoid ring has a partial negative charge (estimated to be in the range 0.08–0.11e) and a partial radical character and the energy of the interaction is estimated to be −11.16 kcal mol⁻¹.

Enantioselectivity of chiral di­hydro­myricetin in multicomponent solid solutions regulated by subtle structural mutation

A series of multicomponent cocrystal solvates of chiral di­hydro­myricetin with caffeine (CAF) or theophylline (THE) crystallized as two distinct types of solid solution differing in mixing scale of enantiomers spanning several orders of magnitude. This remarkable impact on enantiomer discrimination was simply achieved by the reduction of a methyl group of CAF to the THE coformer, which was attributed to the hydrogen-bonding donor–acceptor capacity coformers.

Natural strategies for creating non-equilibrium morphology with self-repairing capability towards rapid growth of excellent YBa₂Cu₃O_7−δ crystals

The self-repairing nature of rapid YBa₂Cu₃O_7−δ growth with overgrowing features is revealed and non-equilibrium morphology is demonstrated to be a prerequisite self-repairing activator.

Bone mineral properties and 3D orientation of human lamellar bone around cement lines and the Haversian system

The hierarchical organization of bone is a key feature of this important biomineralized tissue. A combination of small- and wide-angle X-ray scattering tensor tomography with diffraction tomography and synchrotron computed tomography demonstrates how mineral properties and the orientational relationship between mineral and nanostructure vary across the tissue.

Dynamic correlations and possible diffusion pathway in the superionic conductor Cu_2−xSe

Very high-resolution X-ray scattering data are used to study the disordered structure of Cu_2−xSe in the high-temperature superionic phase.

Formation of ibrutinib solvates: so similar, yet so different

Four different mechanisms of solvate formation were observed and explained for four solvates of the pharmaceutical substance ibrutinib with the series of solvents fluoro­benzene, chloro­benzene, bromo­benzene and iodo­benzene.

Structural and biochemical insights into PsEst3, a new GHSR-type esterase obtained from Paenibacillus sp. R4

Crystal structures of PsEst3 complexed with various ligands and its biochemical characterization indicate the emergence of a new GHSR-type lipase/esterase and reveal the relationship between its structure and function.

Structural and biochemical insights into Zn²⁺-bound EF-hand proteins, EFhd1 and EFhd2

The EF-hands within the crystal structures of the Zn²⁺-bound EFhd1 and EFhd2 core domains coordinate Zn²⁺ ions. EFhd1 and EFhd2 exhibited Ca²⁺- and Zn²⁺-independent actin binding and Ca²⁺- and Zn²⁺-dependent actin-bundling activity, and these suggest the possibility that both Ca²⁺ and Zn²⁺ act to regulate EFhd1 and EFhd2 in physiological processes.