Purification and preliminary crystallographic studies of CutC, a novel copper homeostasis protein from Shigella flexneri.

CutC is a novel copper homeostasis protein containing 248 amino acids. Here we report the cloning, expression, purification, crystallization and preliminary X-ray crystallographic studies of CutC from Shigella flexneri 2a. Purification of CutC and its selenomethionine (SeMet) derivate were done using immobilized metal ion affinity chromatography, size-exclusion and ion-exchange chromatography.

Surface morphology and kinetic properties in rapid growth of EAFP protein crystals investigated by atomic force microscopy.

The whole process of EAFP protein monoclinic crystal growth with an extremely fast rate has been observed by atomic force microscopy. The results showed that the patterns of the growth images in rapidly growing crystals are complicated. The two-dimensional multi-layered stacks of growth steps are characteristic of higher supersaturation and the growth of steps proceeds in a manner of strong anisotropic spiral dislocations dominantly under lower supersaturation conditions.

Purification, crystallization and initial structural solution of a new alpha-like toxin with cardiac toxicity from scorpion Buthus martensii Karsch.

An alpha-like toxin named BmK M7 active on both mammals and insects has been purified from the venom of scorpion Buthus martensii Karsch (BmK) recently. The electrophysiological experiments showed that M7 can bind to human cardiac Na+-channel and modify its normal properties, hence can be considered as a cardiotoxin. Single crystals of M7 have been obtained by hanging-drop vapor diffusion method using ammonium sulfate as precipitant in Tris-HCl buffer at pH 8.

Crystallization and preliminary crystallographic studies of a novel antifungal protein with five disulfide bridges from Eucommia ulmoides Oliver.

Two antifungal proteins, named Eucommia antifungal peptides 1 and 2 (EAFP1 and EAFP2), have been purified from the bark of the tree E. ulmoides Oliver and show a relatively broad spectrum of antifungal activity against several agriculturally important plant pathogens. One of these small proteins (EAFP2) has been crystallized.

cDNA cloning, high-level expression, purification, and characterization of an avian Cu,Zn superoxide dismutase from Peking duck.

As a special species of avian, Peking duck is often used as a model for exploring effective factors against cardio-cerebrovascular diseases, and therefore investigations of antioxidant enzymes including superoxide dismutase are intriguing. By using 3(')-RACE with a gene-specific primer, a cDNA encoding duck Cu,Zn SOD was amplified from the total RNA extracted from Peking duck liver. Three free cysteine residues are found in the deduced amino acid sequence of duck SOD, among which Cys153 at the carbonyl-terminal is a distinctive feature.

Tetra-N-confused cyclohexapyrrole: the unusual product formed by condensation of 3,3'-dipyrromethane with tripyrrin-aldehyde.

Novel tetra-N-confused cyclohexapyrrole is synthesized for the first time via condensation of tripyrrinone-aldehyde with bis(2,4-dimethylpyrrole-3-yl)methane in the presence of p-toluenesulfonic acid monohydrate. X-ray crystal analysis indicates that it adopts a nonplanar conformation with a conelike shape.