Acid interaction

Our potential is a sum of smooth surface potentials that model amino acid-solvent interactions and of smooth pair potentials that model amino acid-amino acid interactions. As in [24], we take as essential only the Ca atoms. 

Steitz, T.A. Stmctural studies of protein-nucleic acid interaction the sources of sequence-specific binding. 

Harrison, S.C., Sauer, R.T. (eds.) Protein-nucleic acid interactions. Curr. Opin. Strue. Biol. 4 1-35, 1994. 

Chen, Z., et al. Protein-nucleic acid interactions in a spherical virus the structure of beanpod mottle virus at 3.0 A resolution. Science 245 154-159, 1989. 

In a process said to be operated in Britain castor oil is subjected to alkaline fusion under critically controlled conditions to produce a mixture of methyl hexyl ketone and w-hydroxydecanoic acid. Interaction of these two materials at higher... 

The anhydride or acyl chloride and the catalyst (proton acid or Lewis acid) interact leading to the acylating agent [formulated here for brevity as an acyl cation (83)]. ... 

Activation of the Dienophile by Lewis Acids, Interactions, Reaction Course, and Transition-state Structures... 

Figure 3.5-3 The hydrogen bond (Lewis acid) interaction of an...

From the data, the liquid is shown to have tetrahedrally coordinated aluminium with three chlorines and the isocyanate group attached. The neutron data clearly shows nitrogen, as opposed to sulfur, coordination to the aluminium center, forming an A1C13NCS species, which is consistent with a hard base/hard acid interaction as compared with the softer sulfur donation. It was also possible to show that a tetrahedral chloride environment is present around the lithium. 

A similar study performed by Welton and co-workers studied the rate and selec-tivities of the Diels-Alder reaction between cyclopentadiene and methyl acrylate in a number of neutral ionic liquids [44]. It was found that endo. exo ratios decreased slightly as the reaction proceeded, and were dependent on reagent concentration and ionic liquid type. Subsequently, they went on to demonstrate that the ionic liquids controlled the endo. exo ratios through a hydrogen bond (Lewis acid) interaction with the electron-withdrawing group of the dienophile. 

The action of a peptidase can be neutralized by an inhibitor. Some inhibitors are very broad in their action and are capable of inhibiting many different peptidases, including peptidases of different catalytic types. Some inhibitors are assumed to be specific for a particular catalytic type, but can inhibit peptidases of different types. Leupeptin, for example, is widely used as an inhibitor of serine peptidases from family SI, but it is also known to inhibit cysteine peptidases from family Cl. Cysteine pqrtidase inhibitors such as iodoacetic acid interact with the thiol of the catalytic cysteine. However, this reduction can occur on any thiol group and can affect other, predominantly intracellular, peptidases with a thiol dependency. One example is thimet oligopepti-dase. Metal chelators such as EDTA can inhibit meta-llopeptidases, but can also affect peptidases that have a requirement for metal ions that is indq>endent of their catalytic activity, such as the calcium-dependent cysteine endopqrtidase calpain 1. 

CD spectroscopy has been used extensively to study peptide-nucleic acid interactions. Conformation changes induced by either the peptide or nucleic acid can be detected readily using this spectroscopic technique. Although the CD spectra of... 

The exact nature of metal-poly(phosphonic acid) interaction is unknown (Ellis, 1989) although a number of structures can be drawn (Figure 8.3). 

Based on the fact that pi-acids interact with the trinuclear gold] I) pi-bases, TR(carb) and TR(bzim), the trinuclear 3,5-diphenylpyrazolate silver(I) complex was reacted with each. Mixing [Au3(carb)3] or [Au3(bzim)3] with [Ag3(p,-3,5-Ph2pz)3] in CH2CI2 in stoichiometric ratios of 1 2 and 2 1 produced the mixed metal/mixed ligand complexes in the same gold-silver ratios. The crystalline products were not the expected acid-base adducts. It is suspected that the lability of the M-N bond (M=Au, Ag) in these complexes results in the subsequent cleavage of the cyclic complexes to produce the products statistically expected from the stoichiometry of materials used [74]. As a result of the lability of Au-N and Ag-N bonds, and the stability of... 

Physical Techniques for Alkaloid-Nucleic Acid Interaction. 167... 

Protoberberine Alkaloid-Triplex Nucleic Acid Interaction. 194... 

Keywords Berberine Palmatine Coralyne Polymorphic nucleic acid structures Alkaloid-nucleic acid interactions... 

Appropriately designed biophysical studies can elucidate the mode(s), the binding affinities and the nature of the ligand-nucleic acid interaction that give rise to the observed selectivity and specificities. Thus, it is worthwhile to describe briefly the various physical techniques used to study alkaloid-DNA/RNA interactions. 

D. L. Jones and L. V. Kochian, Aluminum-organic acid interactions in acid soils. 1. Effect of root-derived organic acids on the kinetics of A1 dissolution. Plant Soil 782 221 (1996). 

M. T. Record, Jr., E. S. Courtenay, S. Caley, and H. J. Guttman, Biophysical compensation mechanisms buffering E. coli protein—nucleic acid interactions against changing environments,... 

In the absence of MejSiCl, the catalytic reaction does not proceed. Sily-lation is considered to liberate the catalyst through the formation of the silyl ether (Scheme 6). The Lewis-acidic interaction of chlorosilanes with the carbonyl oxygen is also suggested to facilitate the electron transfer from... 

Arya DP (2005) Aminoglycoside-Nucleic Acid Interactions The Case for Neomycin. 253 ... 

Chaires JB (2005) Structural Selectivity of Drug-Nucleic Acid Interactions Probed by Competition Dialysis. 253 33-53 Cherkinsky M, see Braverman S (2007) 275 67-101... 

Boron being more electropositive than carbon, the fluorines of BF3 (-126 ppm) are more highly shielded than those of CF4 (-65 ppm). When this strong Lewis acid interacts with a Lewis base, as in BF3 OEt2... 

Konovalova, T. A. and L. D. Kispert (1998). EPR and ENDOR studies of carotenoid-solid Lewis acid interactions. J. Chem. Soc. Faraday Trans. 94 1465-1468. 

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