Identification, binding measurements and structure determination of human sirtuin phosphopeptides in complex with human adapter protein 14-3-3σ reveal variations among tight binders and suggest extended binding modes.

YouTube video by International Union of Crystallography

The article by Sharma et al. [(2023), Acta Cryst. F79, 224–230] is corrected.

We present the 1.87 Å resolution structure of M. jannaschii dihydroorotase complexed with the substrate carbamoyl aspartate at room temperature. Contrary to expectations, a flexible loop which is important in catalysis and closes upon substrate binding in order to stabilize the substrate and transition state is observed in both the loop-out and loop-in conformations, with the loop-out conformation having higher occupancy.

The use of polyethylene glycol in the crystallization of biological macromolecules and its appearance in the resulting crystals is discussed.

This article describes the structural characterization of the class IIIb chitinase from Crocus vernus bulbs. Antifungal and chitinase assays have also been performed to evaluate the potential of the enzyme.

In its wild-type form, the flexible two-domain protein InlB392 yielded poorly reproducible crystals that diffracted to low resolution. Single surface substitutions to tyrosine (T336Y) or glutamate (V333E) yielded well diffracting crystals, suggesting that surface properties, rather than interdomain flexibility, might be the primary impediment to crystallization of the wild type.

PF1765 from P. furiosus crystallized from a single protein batch in 104 of 192 conditions, yielding ten high-resolution structures (1.1–1.5 Å) across two space groups. Despite wide chemical variability, the overall fold remained nearly identical, with conserved crystal contacts and hydration sites, while subtle lattice-specific rotameric differences highlight the utility of this protein as a model for studying packing effects and microheterogeneity.

This study advances our understanding of pteridine glycosylation and also provides a structural basis for investigating photosynthetic signaling pathways in cyanobacteria.

This article describes the structural characterization of a short-chain dehydrogenase from the pathogenic bacterium Brucella ovis. In this manuscript, two structures are described: the structure of the apo protein and a structure containing the coenzyme NAD+.

CryoSift is a CNN-based tool that assesses the quality of 2D class averages. The incorporation of CryoSift into cryoSPARC workflows enables automated particle-stack cleaning.

A high-resolution X-ray structure of a Gln143Asn variant of manganese superoxide dismutase (MnSOD) reveals multiple hydrogen peroxide-binding sites beyond the canonical LIG and PEO binding positions within the active site. These findings expand the known landscape of product peroxide-bound states in MnSOD.