The stoichiometric relationship between thiol oxidized and NO reduced was studied for the reaction catalyzed by nitric oxide reductase from Paracoccus denitrificans. The reaction systems consisted of dithiothreitol, ascorbate, phenazine methosulfate, enzyme and NO, or that system minus ascorbate. The mole ratio of thiol groups oxidized to NO reduced was observed to be 2.3 to 1.5 over a range of...

Background: Diazinon (DZN) is an organophosphate pesticide commonly used for pest control in agriculture. It may engender a variety of negative effects in non-target species, including humans and animals. The objective of the present study was to evaluate the ameliorative properties of captopril (CAP), as a thiol containing an angiotensin-converting enzyme inhibitor, against DZN-induced oxidati...

Ornithine aminotransferase was crystallized from rat liver and several properties of the enzyme were studied, including amino acid composition, thiol content, absorbance spectrum, isoelectric point, molecular weight, and appearance under the electron microscope. The half-cystine and thiol contents of the enzyme were equal (0.12 pmole per mg of enzyme), indicating the absence of disulfide bonds ...

We report on the thiol-ene chemistry guided preparation of novel thiolated polymeric nanocomposite films of abundant anionic carboxylic groups for electrostatic enrichment and sensitive electroanalysis of cationic dopamine (DA) in neutral solution. Briefly, the thiol-ene nucleophilic reaction of a carboxylated thiol with oxidized polypyrrole (PPy), which was electrosynthesized on an Au electrod...

Oxidation-reduction (redox) based regulation of signal transduction and gene expression is emerging as a fundamental regulatory mechanism in cell biology. Electron flow through side chain functional CH2-SH groups of conserved cysteinyl residues in proteins account for their redox-sensing properties. Because in most intracellular proteins thiol groups are strongly "buffered" against oxidation by...

The electrochemical quartz crystal microbalance (EQCM) was used to study the electrosyntheses and electrochemical properties of two kinds of polyaniline (PANI)-thiol composite films in aqueous solutions, which were prepared by covalent binding of a thiol to the oxidized forms of PANI (PANI(post)-thiol, protocol A), and electropolymerization of aniline in the presence of a thiol (PANI(poly)-thio...