D-amino acid oxidase ( D-amino acid oxygen oxidoreductase E.C. 1.4.3.3. ) was found to bind various nitroaromatics with characteristic spectral changes similar in form to those caused by benzoate and its analogues. Nitrobenzene and o-nitroaniline were found to be competitive inhibitors of the enzyme. Dissociation constants of nitroaromatics tested were larger than those of the carboxylates exce...

A specific and sensitive assay for disulfide groups has been developed, based on reduction with dithioerythritol or dithiothreitol and determination of the resulting monothiols with 5,5’-dithiobis(2-nitrobenzoic acid) in the presence of arsenite. The dissociation constants for the complexes formed between arsenite and dithioeqthritol, dithiothreitol, 1,3-dithioglycerol, and 1,2-dithioglycerol h...

acid complexes were determined. The dissociation constants of the amino acids determined are; alanine (10.29), arginine (12.02), asparagine (9.39), glycine (9.87), histidine (7.01), lysine (9.28), methionine (9.68), phenylalanine (9.61), proline (10.53), threonine (10.31), tryptophan (9.77), and valine (10.28). The ratio of metal to amino acid determined for the complexes is 1:3, except for Cu ...

Dissociation constants (pK, 20°C) of D-galacturonic acid, D-glucuronic acid, their O-methyl derivatives, as well as of the corresponding 4,5-unsaturated substance have been determined by means of discontinuous Potentiometrie titration. The found pK values have been interpreted from the point of view of inductive and mesomeric effects, and nonbonding interactions. It is demonstrated that the eff...

MATHEWS and WALKER [1909] and, in greater detail, Dixon and Tunnicliffe [1923] have demonstrated the great significance of the hydrogen ion activity in relation to the rates of oxidation and of autoxidation of a number of thioacids. To assist the analysis of these results and of certain observations of our own it became desirable to know the dissociation constants of cysteine, thioglycollic aci...

Freshwaters are recognized as dynamic systems that may be far-removed from equilibrium. A kinetic approach using the competing ligand exchange method with Chelex 100 as the competing ligand and inductively coupled plasmamass spectrometry to measure the dissociation kinetics was used to investigate the chemical speciation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(II) in model sol...

The interaction of the immobilized triazine dye Cibacron Blue 3G-A with rat, rabbit, sheep, goat, bovine and human serum albumins was studied by affinity gel electrophoresis. Dissociation constants were estimated in each instance and showed human serum albumin to have a significantly higher affinity for the dye than did albumin from any other species. Pretreatment of the defatted proteins with ...

Triplex forming oligonucleotides (TFOs) are the most commonly used approach for site-specific targeting of double stranded DNA (dsDNA). Important parameters describing triplex formation include equilibrium binding constants (K(eq)) and association/dissociation rate constants (k(on) and k(off)). The 'fluorescent intercalator displacement replacement' (FIDR) assay is introduced herein as an opera...