Benzoate, binding

Brown GB, Gaupp JE, Olsen RW (1988) Pyrethroid insecticides stereospecific allosteric interaction with the batrachotoxinin-a benzoate binding site of mammalian voltage-sensitive sodium channels. Mol Pharmacol 34 54-59... 

Pauwels, P.J., Leysen, J.E., Laduron, P.M. pH] Batrachotoxinin A20-a-benzoate binding to sodium channels in rat brain characterization and pharmacological significance, Eur. J. Pharmacol. 1986, 124, 291-298. 

Figure 12.4 (a) Dihydrotestosterone (DHT) and DHT benzoate binding to the androgen receptor. Local induced fit is necessary to accommodate the additional volume of the benzoate group. The image was created with PyMol. See color plates. 

The open-shell configuration of the iron cluster surface has been considered in the definition of the spin magnetic moment of the I ev - CyH C H-adsorbed ensembles [20]. The neutral benzoate binding energies (BE) were calculated according to the following equation ... 

Ibogaine inhibited (Ki 8.1 yu.M) [3H]batrachotoxin A 20-a-benzoate binding to voltage-dependent sodium channels in depolarized mouse neu-... 

Upon benzoate binding intramolecular hydrogen bonds are disrupted and this binding event leads to helix uncoiling. This behavior was in contrast to most of the foldamers described, where anion binding induces helicity or causes helicity inversion. ... 

The direction of sodium benzoate and benzoic acid penetration of the cyclohexa-amylose cavity in aqueous solution has been determined by n.m.r. spectroscopy of the respective cycloamylose complexes. Results suggested that benzoic acid has a strong preference for binding in the cycloamylose cavity, while sodium benzoate binding is more random. Both compounds form 1 1 complexes with cyclohexa-amylose. 

In the elucidation of the X-ray structure of hCP by the method of isomorphous replacement, gold and mercury heavy atom derivatives were utilized. In the case of the mercury derivative, p-chloromercury-benzoate, the heavy atom bound to the free sulphydryl residue, C221, but for the gold cyanide derivative the gold atom was found to bind in the vicinity of the trinuclear copper cluster. A realistic explanation of this... 

In a series of ten morphine 3-benzoates, large differences in rates of enzymatic hydrolysis were seen [122], In 80% human plasma at pH 7.4 and 37°, the unsubstituted 3-benzoate had a tm value of 0.6 h, whereas esters of 2,6-disubstituted benzoic acid were much more resistant to enzymatic attack (t1/2 ranging from 60 h for the dimethylbenzoate to 300 h for the dichloro-and dimethoxybenzoates). Although these results point to marked steric hindrance, electronic effects cannot be excluded but escape characterization because of the limited series. Furthermore, and as mentioned repeatedly in this text, the possibility of binding to plasma proteins is a complicating factor that should be kept in mind. 

At the cellular level, the major electrophysiological effect appears to be rate-dependent blockade of sodium channels [22]. The onset for this Class I effect (64 + 9% of the final depression of between the first and second beat of the train) was similar to that for Class IB agents [23]. The offset rate (recovery of from rate-dependent depression) for amiodarone was 1.48 s. This value falls between those seen for Class IB agents (200-500 ms) and lA agents (2.3-12.2 s) [23]. Amiodarone inhibited the binding of pH]ba-trochotoxinin A 20a-benzoate to the sodium channel, suggesting that it binds to inactivated sodium channels [24]. 

A model accounting for the observed sense of absolute stereoinduction is based upon the coordination mode revealed in the crystal structure of the cyclometallated C,0-benzoate complex [280]. It is postulated that aldehyde binding by the a-allyl haptomer occurs such that the allyl moiety is placed between the naphthyl and phenyl moieties of the hgand, allowing the aldehyde to reside in a more open enviromnent. In the favored mode of addition, the aldehyde C-H bond projects into... 

As deduced from the DNA sequence of the gene, AMDase contains four cysteine residues. Since a-halocarboxylic acids are generally active alkylating agents there is a possibility that a-bromophenylacetic acid reacts with several cysteine residues of the enzyme. Therefore, we tried to clarify how many cysteine residues react with this inhibitor. It is well established that when p-chloromercuri-benzoate (PCMB) binds to a cysteine residue, the absorbance at 255 nm increases due to the formation of an aryl-Hg-S bond. Thus it is possible to estimate the number of free S-H residues of the enzyme by titration with PCMB solution (Fig. 6). When the native enzyme had reacted with PCMB, the absorbance at 255 nm increased by 0.025. On the other hand, when PCMB solution was added to the enzyme solution after the enzyme was incubated with a-bromophenyl-... 

Complexation with caffeine and theophylline-7-acetate depresses the rate of alkaline hydrolysis of substituted phenyl benzoates and is consistent with the formation of molecular complexes with 1 1 stoichiometry between the hosts and esters stacking of the xanthines is excluded as an explanation in the range of concentrations studied. Inhibition of hydrolysis is attributed to repulsion of the hydroxide ion from the host-ester complex by the extra hydrophobicity engendered by the xanthine host, as well as by the weaker binding of the transition state to the host compared with that in the host-ester complex. ... 

A para-substituent may stabilize mesomerically either the conjugate acid of an acid-base pair rather more than it stabilizes benzoic acid, or it may stabilize the conjugate base rather more than it stabilizes the benzoate anion. The first situation is found in car-boxonium ions [13], where the delocalization of the positive charge on to a mesomerically electron-donating substituent stabilizes the cation. A similar resonance in the benzoic acid molecule [14] involves a separation of charge and affects the binding of the proton... 

An example of more complex phenolics is coniferyl benzoate (F ig. 11.2), which inhibits feeding in birds (Jakubas etal, 1989), as discussed below. It binds to skin proteins and dietary proteins. 

To date the evidence seems to favor the binding of tumor promoter to phospholipid in the cell membrane. Specific binding of [3h]TPA to mouse epidermal particulate matter is susceptible to phospholipases C and A2, less susceptible to protease, and completely resistant to glycosidase (32). Photoaffinity labelling studies with [20-3h]-phorbol 12-p-azidobenzoate 13-benzoate indicates that the irreversible binding of this photolabile phorbol ester to mouse brain membrane is predominantly to the phospholipid (specifically phosphatidylethanolamine and phosphatidylserine) portion rather than to the protein portion (33). 

Tetrahedral tetraazonium compounds 5a and 5b, developed by Schmidt-chen, bind carboxylates, such as formiate, acetate, and benzoate, among a variety of other anions [8]. Although these receptors do not display hydrogen bond interactions, they are endowed with well localized polycationic centers, which are independent on the acidity of the medium. A ditopic receptor build up of both a 5a and a 5b subunits bridged by a p-xylylene spacer showed selectivity towards the largest members of a series of dianionic probes [9],... 

Figure 15-11 Stereoscopic view of the benzoate ion in its complex with D-amino acid oxidase. A pair of hydrogen bonds binds the carboxylate of the ligand to the guanidinium group of R283. Several hydrogen bonds to the flavin ring of the FAD are also indicated. Courtesy of Retsu Miura.161...

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