Secret life of importin-β; solenoid flexibility as the key to transport through the nuclear pore

A significant advance in the area of nuclear transport, which also has important implications for understanding the limitations of crystallization approaches, is discussed.

Impact of the crystallization condition on importin-β conformation

Two crystal structure forms of the highly flexible HEAT-repeat protein importin-β from C. thermophilum obtained under divergent crystallization conditions revealed different conformations. SAXS experiments and the analysis of other pairs of importin-β complex structures retrieved from the Protein Data Bank suggest that an increase in the PEG present in the crystallization condition leads to a more elongated conformation of importin-β.

Crystal structure of a dimerization domain of human Caprin-1: insights into the assembly of an evolutionarily conserved ribonucleoprotein complex consisting of Caprin-1, FMRP and G3BP1

Crystal structures of a fragment (residues 132–251) of human Caprin-1 shed lights onto the homodimerization of Caprin-1 and its interactions with partner proteins.

On the influence of crystal size and wavelength on native SAD phasing

Diffraction experiments were carried out at different wavelengths (1.9, 2.7, 3.0 and 3.3 Å) using lysozyme and ferredoxin reductase crystals of various sizes to investigate the influence on native SAD phasing.

Thermal contraction of aqueous glycerol and ethylene glycol solutions for optimized protein-crystal cryoprotection

Measurements of the T = 77 K glass-phase densities of drops with volumes down to 70 pl are used to determine the concentration-dependent thermal contraction of aqueous glycerol and ethylene glycol solutions. Applications in optimizing cryocrystallographic outcomes by matching the contractions of external and internal solvent to those of the crystal and internal solvent spaces are discussed.

Novel protein–inhibitor interactions in site 3 of Ca²⁺-bound S100B as discovered by X-ray crystallography

A structure-based drug-discovery program is under way in order to identify and develop small-molecule inhibitors of S100B for the treatment of malignant melanoma. X-ray crystallographic analysis of two S100B inhibitors reveals newly identified inhibitor–target interactions within site 3 of Ca²⁺-bound S100B. These data contribute to the structural biology knowledge base for this target, which is important for rational drug-design efforts.

A crystallographic study of human NONO (p54^nrb): overcoming pathological problems with purification, data collection and noncrystallographic symmetry

The structure determination of the NONO homodimer is reported, detailing the challenges in protein purification and identifying and overcoming overlapping reflections.

Transferable aspherical atom model refinement of protein and DNA structures against ultrahigh-resolution X-ray data

This paper presents the advantages of using the transferable aspherical atom model of macromolecular structure refinement against ultrahigh-resolution X-ray data over the classic independent-atom model approach in terms of final crystallographic statistics, the description of atomic displacement parameters and the quality of electron-density maps.

DNA polymorphism in crystals: three stable conformations for the decadeoxynucleotide d(GCATGCATGC)

The DNA decamer d(GCATGCATGC) crystallizes in three distinct conformations on minor changes in the crystallization condition. Two different conformations (double fold and B-type helix) are present in the same unit cell.

Effect of impurities and post-experimental purification in SAD phasing with serial femtosecond crystallography data

The effect of sample impurities on SAD phasing of SFX data has been studied using simulated data. It was found that small amounts of impurities can seriously affect the results, while post-experimental purification is capable of improving the result to nearly resemble that from a pure sample.

Identification of the critical linker residues conferring differences in the compactness of NS5 from Dengue virus serotype 4 and NS5 from Dengue virus serotypes 1–3

The residues Lys271, Ser266 and Thr267 of the linker region that connects the methyltransferase and RNA-dependent RNA polymerase domains of dengue virus NS5 serotype 4 are important for differential compactness.

Biochemical and structural characterization of Klebsiella pneumoniae oxamate amido­hydrolase in the uric acid degradation pathway

The structure of K. pneumoniae HpxW, an oxamate amidohydrolase, has been determined and the kinetics of the wild-type enzyme and two active-site variants have been characterized. Based on these data, a mechanism for the HpxW-catalysed reaction is proposed.

Recovery of data from perfectly twinned virus crystals revisited

An iterative method of map recovery for perfectly merohedrally twinned crystals in the presence of noncrystallographic symmetry is reimplemented and released and an independent metric of success is provided.