Grigor'eva_1986_Bioorg.Khim_12_1164

Reference

Title : [Selectivity of the effect on cholinesterase of stereoisomers of thiophosphonates with asymmetrical phosphorus atoms] - Grigor'eva_1986_Bioorg.Khim_12_1164
Author(s) : Grigor'eva GM , Krasnova TI , Abduvakhabov AA , Abdukakharov VS
Ref : Bioorganicheskaia Khimiia , 12 :1164 , 1986
Abstract :

The inhibitory action of stereoisomers of organophosphorous compounds with asymmetric phosphorous atom, (CH3)2CHO(CH3)P(O)SCH2CH2SC2H5 and (CH3)2CHO(CH3). .P(O)(CH2)3CH3, on acetylcholinesterase from nervous ganglia of cockroach Periplaneta americana and bovine erythrocytes as well as on horse serum butyrylcholinesterase was studied at pH 7.5 and 25 degrees C. It was found that the interaction of the inhibitors with cholinesterases has a complex type and includes reversible and irreversible stages resulting in the formation of noncovalent enzyme-inhibitor complex and phosphorylation of the enzyme, respectively. The affinity constants Ka, phosphorylation rate-constants kp, bimolecular reaction constants kII for enzyme inhibition, as well as the dissociation constants Ki, r for unproductive sorbtion of inhibitor were determined. Much greater selectivity in the action of (-)isomers of both thiophosphonates, as compared to (+)isomers, on acetylcholinesterases were observed, the effect being most pronounced for the cockroach enzyme. On the other hand, no marked differences were discerned between isomers in their binding to butyrylcholinesterase. The stereospecificity of the enzymes under study at different stages of interaction with the inhibitors was characterized.

PubMedSearch : Grigor'eva_1986_Bioorg.Khim_12_1164
PubMedID: 3778536

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Citations formats

Grigor'eva GM, Krasnova TI, Abduvakhabov AA, Abdukakharov VS (1986)
[Selectivity of the effect on cholinesterase of stereoisomers of thiophosphonates with asymmetrical phosphorus atoms]
Bioorganicheskaia Khimiia 12 :1164

Grigor'eva GM, Krasnova TI, Abduvakhabov AA, Abdukakharov VS (1986)
Bioorganicheskaia Khimiia 12 :1164