Expanding beyond biological crystallography

The Acta Cryst. D Editors look forward to a change in scope and a new subtitle for the journal.

High-density grids for efficient data collection from multiple crystals

A high-density sample mount has been developed for efficient goniometer-based sample delivery at synchrotron and XFEL sources.

Structure of D-alanine-D-alanine ligase from Yersinia pestis: nucleotide phosphate recognition by the serine loop

Five crystal structures of D-alanine-D-alanine ligase from Y. pestis have been determined at 1.7–2.5 Å resolution: apo, AMP-bound, ADP-bound, adenosine 5′-(β,γ-imido)triphosphate-bound, and D-alanyl-D-alanine- and ADP-bound structures. The serine loop is mainly responsible for the conformational change in the substrate nucleotide phosphates.

The structure of VgrG1 from Pseudomonas aeruginosa, the needle tip of the bacterial type VI secretion system

This article presents the crystal structure of full-length VgrG1 from P. aeruginosa, a component of the type VI secretion-system machinery essential in bacterial infection.

Lattice filter for processing image data of three-dimensional protein nanocrystals

A specialized filter for finding lattices in images of three-dimensional nanocrystals devoid of any contrast is described.

Structure of the ectodomain of the electron transporter Rv2874 from Mycobacterium tuberculosis reveals a thioredoxin-like domain combined with a carbohydrate-binding module

The structure of the extramembrane portion of the CcdA-family member Rv2874 from M. tuberculosis reveals a previously unseen juxtaposition of a thioredoxin-like domain with a carbohydrate-binding module, suggesting a role in cell-wall carbohydrate processing.

Molecular architecture of the nucleoprotein C-terminal domain from the Ebola and Marburg viruses

Crystal structures of the C-terminal domains of the Ebolavirus nucleoproteins (NP^Ct) from the Bundibugyo and Taï Forest species (BDBV and TAFV, respectively) have been determined. The structures show high similarity to that reported for the Zaire Ebolavirus NP^Ct. However, NMR data revealed that the corresponding domain from the NP of the related MARV species of Marburgvirus is distinctly different.

Bacillus licheniformis trehalose-6-phosphate hydrolase structures suggest keys to substrate specificity

Wild-type and mutant structures of B. licheniformis trehalose-6-phosphate hydrolase suggest new insight into the characteristics and substrate specificity of trehalose-6-phosphate hydrolase.

A technique for determining the deuterium/hydrogen contrast map in neutron macromolecular crystallography

The deuterium/hydrogen neutron contrast map, which was calculated using subtraction in real space, demonstrated the powerful detectability of H/D exchange in the neutron structure determination of a ribonuclease A crystal.

Atomic resolution experimental phase information reveals extensive disorder and bound 2-methyl-2,4-pentanediol in Ca²⁺-calmodulin

Experimental phase information at 1.0 Å resolution was used to validate a more complete multiple-conformation model of disorder in Ca²⁺-calmodulin and identified bound 2-methyl-2,4-pentanediol (MPD) in multiple regions of the protein. This bound MPD is likely to contribute to some of the previously noted peculiar features of the Ca²⁺-calmodulin crystal structure.

In meso in situ serial X-ray crystallography of soluble and membrane proteins at cryogenic temperatures

A method for performing high-throughput in situ serial X-ray crystallography with soluble and membrane proteins in the lipid cubic phase at cryogenic temperatures (100 K) is described. It works with nanogram to single-digit microgram quantities of protein and lipid (and ligand when present), and is compatible with both high-resolution native data collection and experimental phasing without the need for crystal harvesting.

Crystal structures of the components of the Staphylococcus aureus leukotoxin ED

Crystal structures of LukE and LukD from S. aureus are reported at 3.20 and 1.70 Å resolution, respectively.

Probing the effectiveness of spectroscopic reporter unnatural amino acids: a structural study

The structural implications of incorporating spectroscopic reporter unnatural amino acids into proteins is explored using X-ray crystallography. Four protein crystal structures with 4-cyano-L-phenylalanine or 4-ethynyl-L-phenylalanine incorporated into green fluorescent protein at two unique sites are described.

Re-refinement of the spliceosomal U4 snRNP core-domain structure

The structure of the spliceosomal U4 snRNP core domain has been re-refined following molecular replacement using the minimal U1 snRNP as a search model. RNA-omit maps show that the U4 Sm-site nucleotides AAUUUUU are bound to the seven Sm proteins SmF–SmE–SmG–SmD₃–SmB–SmD₁–SmD₂ in the same manner as the U1 Sm-site nucleotides AAUUUGU except at the U-to-G substitution in SmD₁.

Mask-based approach to phasing of single-particle diffraction data

A procedure is suggested for ab initio phasing of diffraction data for single-particle studies. The procedure is based on a Monte Carlo-type search for connected binary masks approximating electron-density distribution.

Structure of TSA2 reveals novel features of the active-site loop of peroxiredoxins

The crystal structure of TSA2 reveals a novel conformation of a strictly conserved proline and explains the differences in pK_a between yeast peroxiredoxins.

Structures of designed armadillo-repeat proteins show propagation of inter-repeat interface effects

Designed armadillo-repeat proteins are promising scaffolds for modular peptide-recognition systems. The crystal structures of His-Y_IIIM₄A_II, His-Y_IIIM₅A_II and Y_IIIM₅A_II highlight structural heterogeneity in full-consensus designs and aid the improvement of future constructs.

A new default restraint library for the protein backbone in Phenix: a conformation-dependent geometry goes mainstream

The default geometry restraints used in Phenix for the protein backbone have been upgraded to account for the known conformation-dependencies of bond angles and lengths.

Structural and functional insights into an archaeal L-asparaginase obtained through the linker-less assembly of constituent domains. Corrigendum

The article by Tomar et al. [(2014). Acta Cryst. D70, 3187–3197] is corrected.

Crystals, X-rays and Proteins. Comprehensive Protein Crystallography