The effects of chloride and sulfate salts of tetrapropylammonium (TPA(+)) and guanidinium (Gdm(+)) on the conformational stabilities of tryptophan zipper (trpzip) and α-helical (alahel) peptides were measured by circular dichroism spectroscopy. Like Gdm(+), TPA(+) interacts with the planar tryptophan indole group, perturbing the conformational stability of trpzip peptides. TPA(+) effects are la...

In the title compound, [Cd(SO(4))(C(12)H(8)N(2))(2)]·C(3)H(8)O(2), the Cd(II) atom has a distorted octa-hedral coordination composed of four N atoms from two chelating 1,10-phenanthroline ligands and two O atoms from an O,O'-bidentate sulfate group. The two chelating NCCN groups subtend a dihedral angle of 82.21 (9)°. The Cd(II) ion, the S atom and the middle C atom of the propane-1,3-diol solv...

A beta-mannanase (EC 3.2.1.78) from Vibrio sp. strain MA-138 was purified by ammonium sulfate precipitation and several chromatographic procedures including gel filtration, adsorption, and ion-exchange chromatographies. The final ion-exchange chromatography Mono Q yielded one major active fraction and three minor active fractions. The major active fraction was purified to homogeneity on the bas...

oil exploration and production zones are very frequently contaminated with petroleum hydrocarbons or its derivatives. the most important exploration and production zones are located in south-west and south of the country, in iran. masjed soleiman city is located on an oil field. the soil of this region has been affected by the petroleum composition. mach petroleum seepages and springs (asphalt,...

The fully automated combustion ion chromatography (CIC) system presented here combines a highly efficient combustion system with the separation power of ion chromatography (IC). CIC allows for the simultaneous, speciated trace analysis of halide (F, Cl, Br, and I) and sulfur compounds (as sulfate) from subppm to percent levels in any nonaqueous sample matrix. Chloride and sulfur recoveries in t...

The isolation, purification and structural characterization of human liver heparan sulfate are described. 1H-NMR spectroscopy demonstrates the purity of this glycosaminoglycan (GAG) and two-dimensional 1H-NMR confirmed that it was heparan sulfate. Enzymatic depolymerization of the isolated heparan sulfate, followed by gradient polyacrylamide gel, confirmed its heparin lyase sensitivity. The con...