Binding, of anions

Heegard, N. H. H. and Robey, R A., Use of capillary zone electrophoresis to evaluate the binding of anionic carbohydrates to synthetic peptides derived from human serum amyloid P component, Anal. Chem., 64, 2479, 1992. 

Ryeom, SW, Silverstein, RL, Scotto, A, and Sparrow, JR, 1996a. Binding of anionic phospholipids to retinal pigment epithelium may be mediated by the scavenger receptor CD36. J Biol Chem 271, 20536-20539. 

Binding of anions, cations, and organic substrates. In order to probe the roles of the different types of copper atoms and the nature of the electron transfer pathways between them, a variety of complexes of hCP with inhibitors of oxidase activity and... 

Compound [22] forms thermodynamically stable complexes with Ba2+ and K+. The binding of anions by free [22] is relatively weak the metal cation therefore cooperates in the anion complexation process. Electrochemical studies using CV and SWV have shown that [22] is capable of electrochemi-cally recognizing both cations and anions simultaneously and readers are urged to consult the original publication for a detailed explanation of this effect. 

Tail, J.F., and Smith, C., 1999, Phosphatidylserine receptor Role of CD36 in binding of anionic phospholipid vesicles to monocytic cells, J. Biol. Chem. 274 3048-3054. 

The results may provide a guidepost for designing hybrid assemblies which are capable of performing effective binding of anionic and hydrophobic guests that are not incorporated into the anionic bilayer membrane itself macrocyclic... 

Fluorinated hydrocarbons are known to interact strongly even with rather hydrophilic anions. By introducing trifluoromethyl groups into the polymers you mentioned, I would expect a substantial increase in the binding of anions. Did you observe such an effect when introducing the trifluoromethyl labels ... 

I can also endorse Dr. Williams remarks on polarizability effects by citing the early work on binding of anions by proteins (e.g., serum albumin). Some 25 years ago the extent of binding of a series of anions, Cl , Br , SCN", by albumin was found to parallel their polarizabilities. 

There are numerous studies of metal complexation by whole cells indicating that complexation depends on the bacterium, the metal, and pH. It has been found that at low pH, cationic metal complexation is reduced however, binding of anionic metals such as chromate (Cr042 ) and selenate (Se042 ) is increased. Bacteria seem to show selective affinities for different metals. This was demonstrated by a study of the complexation of four metals by four different bacterial genera that... 

ATP4-.242 Results indicated associations to be influenced by macrocyclic and size effects, electrostatic interactions and structural complementarity. Of particular interest in this series is the observed very strong binding of anionic metal ion complexes. The electrochemistry of M(CN)6 /M(CN)4 (M = Fe, Ru) indicates the complexed complex to be nonlabile and the system to undergo a reversible one-electron exchange. The ability of the macrocycle to protect the reactivity of the complex is evidenced by the hindered photoaquation observed for Co(CN)j e [32]NgH8.247 The results of competition studies suggest predominantly coulombic interactions between the metal complex and macrocycle for these 1 1 complexes of complexes . 

There is surprisingly little evidence in the literature about the binding of anions to oxidised P-450. Perhaps F, OH-, Njj, etc. do not bind or have a very low affinity. The redox potential of P-450 is well below 0.0 volts and these properties may well indicate that the heme is already bound by an anion (e.g. RS- see later). The majority of studies of complexes deal therefore with neutral, mostly unsaturated, ligands. 

By appending crown ether moieties to the amidopyrrole skeleton it had been shown that it is possible to both enhance the binding of anions to the cleft by the introduction of caesium cations but only with a limited degree of success (Figure 16).13 Compounds 16 and 17 were synthesized by reaction of the 4 -aminobenzo-15-crown-5 with the 2-methyl-5-mono-acid chloride-3,4-diphenylpyrrole and the analogous 2,5-bis-acid chloride in 28 and 33% respective yields. 

The binding of anionic substrates has been further investigated with examples detailing the complexation of short chain peptides1819 and asymmetric carboxylates.20... 

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