In the structure of the title compound, magnesium hydroxide hydrogenarsenate (6.75/3/4), two different Mg(2+) ions, one located on a site with symmetry 3m. (occupancy 3/4) and one on a general position, as well as two different AsO3(OH) tetra-hedra (symmetry .m. with partial occupancy for the H atom for one, and symmetry 3m. with full occupancy for the H atom for the other) and one OH(-) ion (s...

13C and 35/37Cl NMR relaxation measurements on several model systems demonstrate that the solvation of cellulose by the ionic liquid (IL) 1-n-butyl-3-methylimidazolium chloride ([C4mim]Cl) involves hydrogen-bonding between the carbohydrate hydroxyl protons and the IL chloride ions in a 1 ratio 1 stoichiometry.

The complex of xylan and iodine and its formation in a solution of xylan, CaCl2, and I2+KI was investigated by UV/Vis, second-derivative UV/Vis, and Raman spectroscopy. The complex forms only at very high concentrations of CaCl2, suggesting that when the water available in the solution is not sufficient to fully hydrate the calcium cation the chelation with the hydroxyl groups of the xylan can ...

Gel retardation studies and other experiments indicate that DNA sequences containing the d(GA4T4C)n motif are curved, whereas those of identical composition but with a reverse sequence polarity, the d(GT4A4C)n motif, are straight. Hydroxyl radical cleavage experiments show that d(GA4T4C)n shows a unique signature, whereas d(GT4A4C)n behaves normally. To explain these results at a molecular leve...

Divalent metal ions play a crucial role in catalysis by many RNA and protein enzymes that carry out phosphoryl transfer reactions, and defining their interactions with substrates is critical for understanding the mechanism of biological phosphoryl transfer. Although a vast amount of structural work has identified metal ions bound at the active site of many phosphoryl transfer enzymes, the numbe...

ion, hydrogen addition or electron transfer, while superoxide anion reacts via only hydrogen abstraction and electron transfer (Section 1.2) (5). Although, hydrogen peroxide and singlet oxygen are classified as ROS, they are not radicals and do not necessarily interact with tissue through radical reactions directly (6). Hence, they are not toxic per se but in presence of free radicals or cataly...

qct calculations were performed to study the behavior of energized nh2oh formed by association collision of nh2 radical with oh radical. a potential energy surface that describes the behavior of the title reaction has been constructed by interpolation of ab initio data. h2o, hon, hno, nh3, o, h2no, cis or trans-honh, and h products and two vibrationally energized nh2oh and nh3o adducts were obs...

objective(s) anxiety is a common disorder which afflicts many people in any society and is often accompanied by physiological sensations such as tachycardia, chest pain, shortness of breath, insensitivity, etc. the purpose of present study was to evaluate the putative anxiolytic-like effects of phencyclidine ('-('-phenylcyclohexyl) piperidine, cas 956-90-1, pcp, i) and its methyl and ...

In the crystal structure of the reduced form of the wild-type human peroxiredoxin 5, the presence of a benzoate ion in direct interaction with the peroxidatic cysteine (Cys 47) appeared as a rather intriguing feature since it is known that the benzoate ion can play the role of a specific hydroxyl radical scavenger. The crystal structure of the C47S mutant of the same enzyme has been crystallize...

D-serine is a physiological co-agonist of the N-methyl-D-aspartate receptor. It regulates excitatory neurotransmission, which is important for higher brain functions in vertebrates. In mammalian brains, D-amino acid oxidase degrades D-serine. However, we have found recently that in chicken brains the oxidase is not expressed and instead a D-serine dehydratase degrades D-serine. The primary stru...