CARBAMYLATION AND DECARBAMYLATION OF ACETYLCHOLINESTERASE: EFFECT OF CHOLINE, 3,3‐DIMETHYL‐l‐BUTANOL AND SOME ALLOSTERIC EFFECTORS

@article{Dawson1978CARBAMYLATIONAD,
  title={CARBAMYLATION AND DECARBAMYLATION OF ACETYLCHOLINESTERASE: EFFECT OF CHOLINE, 3,3‐DIMETHYL‐l‐BUTANOL AND SOME ALLOSTERIC EFFECTORS},
  author={M. Dawson},
  journal={Journal of Neurochemistry},
  year={1978},
  volume={30}
}
  • M. Dawson
  • Published 1978
  • Chemistry, Medicine
  • Journal of Neurochemistry
Abstract— Choline is more effective than 3,3‐dimethyl‐l‐butanol (DMB) in protecting bovine erythrocyte AChE against carbamylation by physostigmine sulphate (an ester of methylcarbamic acid). Both of these alcohols bind to dimethylcarbamyl‐AChE and accelerate its decarbamylation. Choline has a higher affinity for the inhibited enzyme, and causes a more rapid reactivation than does OMB. At low ionic strength, various allosteric effectors also bind to the dimethylcarbamylenzyme and accelerate its… Expand
13 Citations
Effect of choline esters on the decarbamylation of dimethylcarbamyl-acetylcholinesterase
TLDR
In kinetic analysis, it was observed that the Ka value of choline was not remarkably altered by butyrylcholine whereas the maximum rate for decarbamylation was enhanced significantly in the presence of butyRYlcholinesterase, suggesting that butyriesrcholine may affect the decarb amylation by interacting with the peripheral sites, different from the central active site which choline is known to interact with. Expand
Procaine as a substrate and possible allosteric effector of cholinesterases
The local anaesthetic procaine showed the properties of an allosteric effector of bovine erythrocyte acetylcholinesterase at low ionic strength; it antagonised inhibition of substrate hydrolysisExpand
Gallamine and tubocurarine as possible allosteric modifiers of soluble acetylcholinesterase activity at physiological ionic strength
TLDR
The present results suggest that allosteric effects of dimethylcarbamyl-acetylcholinesterase may persist at physiological ionic strength, compared with few indications previously that this was so. Expand
Assessment of the competition between tacrine and gallamine for binding sites on acetylcholinesterase
Abstract Gallamine binds to a peripheral anionic site on bovine erythrocyte acetylcholinesterase at low ionic strength and exerts allosteric effects on substrate hydrolysis (increase in maximumExpand
Kinetic, equilibrium and spectroscopic studies on cation association at the active center of acetylcholinesterase: topographic distinction between trimethyl and trimethylammonium sites.
This study examines the importance of electrostatic interactions on ligand association at the active center of acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7). The active-centerExpand
Modification of the kinetic properties of Triton-solubilized rabbit brain acetylcholinesterase by allosteric effectors at low ionic strength
TLDR
The kinetic properties of Triton-solubilized rabbit brain acetylcholinesterase were less sensitive to modification by proposed allosteric effectors than bovine erythrocyte acetyl cholinestersterase, and millimolar concentrations of gallamine and tubocurarine were required to produce observable effects at physiological ionic strength. Expand
3-Carbamyl-N-allylquinuclidinium bromide. Effects on cholinergic activity and protection against soman.
TLDR
It is demonstrated that reversible inhibition of AChE with suppression of acetylcholine synthesis into a single compound, CAB, enhances the protection against organophosphates. Expand
Phenyldichlorophosphate as an aid in studies of decarbamylation of carbamylated acetylcholinesterase.
TLDR
The advantages of the method using phenyldichlorophosphate over conventional methods are particularly evident when decarbamylation is rapid or when in vivo studies are being performed and it is not practical or desirable to run assays immediately on isolation of the tissue. Expand
Cationic and uncharged substrates and reversible inhibitors in hydrolysis by acetylcholinesterase (EC 3.1.1.7). The trimethyl subsite.
TLDR
It is shown that the quaternary ammonium group of acetylcholine and the neopentyl group of 3,3-dimethylbutyl acetate bind at the same subsite, indicating that the binding subsite may be explored more specifically by tert-butyl than by charged reagents. Expand
The precision of results from nonlinear regression analysis of data following a three-parameter one-exponential equation.
  • R. Dawson
  • Chemistry, Medicine
  • Analytical biochemistry
  • 1983
TLDR
The results show that the errors in the computed constants, and particularly the rate constant k, may be considerably magnified with respect to theerrors in the experimental data. Expand
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