Introduction to the SAMPREP special issue

The focused issue on the SAMPREP workshop is introduced. The virtual issue is available at https://journals.iucr.org/special_issues/2025/samprep23/.

Improved structure of mouse gasdermin D: a new blueprint for structure-based drug design

The study presented here provides higher resolution data, improved refinement statistics and additional structural details that were previously unresolved in the deposited model of mouse gasdermin D. The structure described in this paper will be valuable to researchers in structural biology, immunology, pharmacology and cell-death mechanisms.

Biochemical characterization and preliminary X-ray crystallographic analysis of cyanobacterial α-glucan phosphorylases

This report presents the biochemical characterization of phosphorylases from the cyanobacteria Crocosphaera subtropica ATCC 51142 and Synechococcus elongatus PCC 7942, along with preliminary X-ray crystallographic analysis of an isozyme from strain 51142.

Tetrameric structure of Bacillus subtilis DegQ and its predicted interaction with the DegS–DegU two-component system

B. subtilis DegQ is a 46-amino-acid regulatory protein involved in the DegS–DegU quorum-sensing system. It folds into a single α-helix, and four monomers assemble into a tetramer characterized by a four-helix coiled-coil structure.

Crystal structure of D-aspartate oxidase from Cryptococcus humicola UJ1

The crystal structure of Cryptococcus humicola D-aspartate oxidase (chDDO) was determined at 1.70 Å resolution, revealing a unique homotetrameric architecture that distinctly contrasts with the typical dimeric organization of other known D-amino-acid oxidases. This novel oligomerization state is attributed to specific loop insertions and deletions within its FAD-binding and interface domains, facilitating unique inter-subunit interactions, and indicates a distinct substrate-recognition mechanism in chDDO.

PERC: a suite of software tools for the curation of cryoEM data with application to simulation, modeling and machine learning

PERC (profet, EMPIARreader and CAKED) is a suite of open-source Python software tools facilitating the curation of cryoEM data utilizing standard data-science libraries.