issue contents
March 2019 issue
research papers
Open access
Different modes of data collection are explored, and the effect of flux and multiplicity on the resulting quality of the data set is discussed. Advice is offered on how to collect data in the absence of prior knowledge of the sample.
Open access
A broadly applicable, simple and fast data-collection strategy for native SAD is described, which has become the primary choice for experimental phasing among users of the macromolecular crystallography beamline X06DA (PXIII) at the Swiss Light Source. Its usage over the last four years is reviewed.
PDB reference: streptavidin–biotin, 6m9b
Solution structures of complexes between human serum albumin and the two lipidated insulin analogues detemir and degludec are presented and models for the equilibria are suggested.
Open access
The disulfide isomerase α-DsbA2 from Wolbachia pipientisis is unexpectedly homotrimeric and lacks the `shape-shifting' conformational flexibility that defines another trimeric disulfide isomerase, ScsC from Proteus mirabilis.
PDB reference: α-DsbA2, 6eez
Open access
The structure and function of a bacterial trimeric protein disulfide isomerase was investigated by characterising two variants in which key structural regions were deleted. In one case the effect on structure and function was predictable, while in the other we found unintended consequences for both structure and function.
The crystal structure of pyroglutamate (pG) bound PCP I enzyme reveals the mechanism of its pG specificity. The residues of a conserved active-site loop interact with pG via phenylalanine stacking interactions and hydrogen bonds.
This article describes the methodological approach used to solve the structure of human IBA57; to our knowledge, this is the only structure present in the Protein Data Bank which has been solved in-house by remote SAD phasing in space group P1 using only one crystal.
Cysteine proteases are among the most prominent hydrolytic enzymes produced by human distal gut commensal bacteria. Here, the first inactive zymogen structure of a clostripain-like C11 protease family member is reported from the bacterium Parabacteroides distasonis.
PDB reference: distapain zymogen, 6mzo
The heterododecameric complex of a reducing octaheme cytochrome c with its redox partner shows an extended electron transfer pathway.
PDB reference: KsHAOr–KsDH complex, 6h5l
Open access
The solution of a structure of human Rab27a suffering from severe anisotropy and translational noncrystallographic symmetry was aided by identifying diffraction measurements with low information content.
PDB reference: human Rab27a, 6huf
obituaries
Free
Nobel Prize winner Tom Steitz is remembered by his former colleague Poul Nissen.