While new anti-cytokine disease-modifying anti-arthritic drugs for rheumatoid arthritis have been designed via mechanistic approaches, the mechanism of action of a number of more established disease-modifying anti-arthritic drugs has not been elucidated. In the case of d-penicillamine and sodium aurothiomalate, the key structural feature appears to be a free thiol group. However, the role thiol...

Ketene has been found to be a highly specific,acetylating agent for aqueous solution of proteins. It reacts only with amino, thiol, and phenolic hydroxy groups (1). Several investigators (24) have shown that the primary amino groups react most rapidly, while the hydroxy groups of tyrosine are acetylated at a much slower rate. The hydroxy groups in carbohydrate radicals of the protein molecule d...

Thiol/disulfide systems are involved in the maintenance of the redox status of proteins and other molecules that contain thiol/disulfide groups. Leptospirillum ferriphilum DSM14647, an acidophilic bacterium that uses Fe(2+) as electron donor, and withstands very high concentrations of iron and other redox active metals, is a good model to study how acidophiles preserve the thiol/disulfide balan...

Bacteria encounter reactive oxygen species (ROS) as a consequence of the aerobic life or as an oxidative burst of activated neutrophils during infections. In addition, bacteria are exposed to other redox-active compounds, including hypochloric acid (HOCl) and reactive electrophilic species (RES) such as quinones and aldehydes. These reactive species often target the thiol groups of cysteines in...

diazinon is an organophosphate which is extensively used in trade and agriculture. due to its widespread application, its toxicity is common. several studies have shown that organophosphates are able to induce oxidative stress by generating free radicals and depletion of endogenous antioxidants. pomegranate seed oil (pso) possesses anti-inflammatory and antioxidant effects. in this study, the e...

Cyanylation of myosin with 6-thiol’4Clcyanato-9-/3-o-ribofuranosylpurine shows a biphasic effect. During the incorporation of the first 4 mol of cyanide the Mg”+-dependent ATPase activity increases approximately &fold, the Ca*+ activity rises only slightly, and the K+(EDTA) activity falls to approximately 5% of its original value. These enzyme preparations can still be inactivated by N-ethylmal...

1. The purification of creatine kinase from normal and genetically dystrophic chicken breast muscle is described. Enzyme recovery was significantly lower from dystrophic muscle. 2. Both enzymes had the same number of reactive and total thiol groups and had similar specific activities and similar amino acid compositions. 3. No significant differences were observed in sedimentation, electrophoret...

The acid-catalyzed reaction of 1,2-anhydro-3,4,6-tri-O-benzyl-α-d-glucopyranose (7) as glycosyl donor with bis-trimethylsilyl sulfide as acceptor affords the α-thiol. Hence, this sterically hindered S-nucleophile as acceptor should provide with O-glycosyl trichloroacetimidates as glycosyl donors that have nonparticipating groups at C-2, glycosylthiols with the thiol group in axial position. Thi...

Based on plasma-treated single wall carbon nanotubes (SWCNTs), SWCNT/SiO(2) and thiol groups-functionalized SWCNT/SiO(2) hybrids have been fabricated through a sol-gel process. By means of thiol groups, Ag nanoparticles have been in situ synthesized and bonded onto the SiO(2) shell of SWCNT/SiO(2) in the absence of external reducing agent, resulting in the stable carbon nanotube/SiO(2)/Ag nanop...

Thiol esters, such as aeetyl coenzyme A, the principal biological carrier of activated acetyl groups, have generally been supposed to be “energy-rich” compounds; i.e. to have a free energy of hydrolysis at pH 7.0 in the range of -7000 to -14,000 calories per mole. The reported numerical values for the free energy of thiol ester hydrolysis have varied over a wide range (for recent estimates see ...