Interaction between calmodulin and five different spin-labelled chlorophenothiazines.

J L Olivier; D Rainteau; G Bereziat; C Wolf

doi:10.1042/bj2330853

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Interaction between calmodulin and five different spin-labelled chlorophenothiazines.

J L Olivier·D Rainteau·G Bereziat·C Wolf

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Abstract

The binding to purified calmodulin of five spin-labelled derivatives of chlorophenothiazine was investigated by e.s.r. spectrometry and by the antagonizing potency on the calmodulin-dependent activation of myosin light chain kinase. The results of a comparative study and the influence of pH and ionic strength on the binding support the occurrence of an electrostatic binding involving the terminal amino group of the side-chain of the chlorophenothiazine. These results are discussed in relation to the specificity of the interaction that holds the antipsychotic drug-calmodulin complex together.

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Calcium Calmodulin Cyclic N-Oxides Electron Spin Resonance Spectroscopy Hydrogen-Ion Concentration Myosin-Light-Chain Kinase Osmolar Concentration Phenothiazines Protein Binding Protein Kinases Spin Labels Journal Article

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J L Olivier, D Rainteau, G Bereziat, C Wolf. 1986-02-01. Interaction between calmodulin and five different spin-labelled chlorophenothiazines.. https://doi.org/10.1042/bj2330853

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