The effect of preparing lead-based organohalide perovskites under inert conditions has been investigated. We find that when prepared under anhydrous conditions, only poorly crystalline powders were obtained. On exposure to small amounts of moisture a rapid crystallization into the expected cubic unit cell for CH3NH3PbBr3 and tetragonal cell for CH3NH3PbI3 is observed. While the as-prepared iodi...

The C-terminal 232-419 amino acids fragment of endonuclease Sau3AI has been successfully expressed in Escherichia coli with 6 His at its N-terminal. After purification and crystallization, one completed 2.8 A data set was collected using a Rigaku R-AXIS IV++ diffractometer. The plate-like crystals belong to orthorhombic space group P2(1)2(1)2(1) with the cell dimension of a = 34.75, b = 76.82, ...

Many attempts have been made to elucidate the three-dimensional structure from elongation factor Tu, but so far the only crystals suitable for X-ray crystallography contained a partially degraded protein. Here, we report the crystallization of a fully active, intact EF-Tu from thermus aquaticus. The crystals belong to hexagonal space group P6(3)(22) and diffract up to 2.6 A. The cell dimensions...

The asymmetric unit of the title compound, C(14)H(11)ClN(2)O(2)·H(2)O, contains a Schiff base mol-ecule and a water mol-ecule of crystallization. The dihedral angle between the two aromatic rings is 27.3 (4)°. In the crystal structure, mol-ecules are linked into a two-dimensional network parallel to the bc plane by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds involving the water mol-ecules.

The asymmetric unit of the title salt, C(28)H(28)O(3)P(+)·Cl(-)·H(2)O, contains a benzyl-triphenyl-phospho-nium cation, a chloride counter-ion, and a water mol-ecule of crystallization. The 3,4,5-trimeth-oxy substituents of the benzylic functionality are arranged with the 3,5-methyl groups lying approximately in the aromatic ring plane while the 4-methyl group is out of the plane.

Seeding is a versatile method for optimizing crystal growth. Coupling this technique with capillary counter diffusion crystallization enhances the size and diffraction quality of the crystals. In this article, crystals for organic solvent-tolerant recombinant elastase strain K were successfully produced through microseeding with capillary counter-diffusion crystallization. This technique improv...

Electron cryomicroscopy, or cryoEM, is an emerging technique for studying the three-dimensional structures of proteins and large macromolecular machines. Electron crystallography is a branch of cryoEM in which structures of proteins can be studied at resolutions that rival those achieved by X-ray crystallography. Electron crystallography employs two-dimensional crystals of a membrane protein em...

The asymmetric unit of title hydrated salt, C22H46N4 (2+)·2Cl(-)·4H2O, comprises half a centrosymmetric dication, one Cl(-) anion and two water mol-ecules of crystallization. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms, and that the dication features intra-molecular N-H⋯N hydrogen bonds. In the crystal, a three-dimensional artchitecture...

The title compound, C(36)H(30)NP(2) (+)·I(-), was obtained accidently from crystallization of a reaction mixture containing [(Ph(3)P)(2)N]OH and B(OH)(3), which was contaminated with MeI. There are two independent [(Ph(3)P)(2)N](+) cations and two I(-) anions within the asymmetric unit. The central PNP angles are non-linear [137.6 (2) and 134.4 (2)°] and the phenyl substituents on P centres ado...

How protein molecules pack into a crystal remains problematic. Packing units are direct materials for packing into crystals. The group generator method is introduced for automatically identifying the packing unit. By introducing deviations into the nucleation stage of crystallization, we proved that these deviations diminish in further packing. This process illus trates how translation symmetri...