Alhomida_1997_J.Enzyme.Inhib_12_303

Reference

Title : Evaluation of the nature of camel retinal acetylcholinesterase: inhibition by hexamethonium - Alhomida_1997_J.Enzyme.Inhib_12_303
Author(s) : Alhomida AS , Kamal MA , Al-Jafari AA
Ref : J Enzyme Inhib , 12 :303 , 1997
Abstract :

Acetylcholinesterase (AChE, EC 3.1.1.7) has been demonstrated in retinas of several species, however, the nature of the interaction of AChE with specific inhibitors are very limited in the literature and the mode of inhibition of camel retinal AChE by hexamethonium has been studied. Hexamethonium reversibly inhibited AChE in a concentration dependent manner, the IC50 value being c. 2.52 mM. The Km for the hydrolysis of acetylthiocholine iodide was found to be 0.087 mM and the Vmax was 0.63 mumol/min/mg protein. Dixon, as well as Lineweaver-Burk, plots and their secondary replots indicated that the nature of the inhibition is of the hyperbolic (partial) mixed type, which is considered to be a partial competitive and non-competitive mixture. The values of Ki(slope) and KI(intercept) from a Lineweaver-Burk plot were estimated as 0.30 mM and 0.17 mM, respectively, while Ki from a Dixon plot was estimated as 0.725 mM. The Ki was greater than KI indicating that hexamethonium has a greater affinity of binding for the active site than the peripheral site of the camel retina AChE.

PubMedSearch : Alhomida_1997_J.Enzyme.Inhib_12_303
PubMedID: 9502051

Related information

Inhibitor Hexamethonium

Citations formats

Alhomida AS, Kamal MA, Al-Jafari AA (1997)
Evaluation of the nature of camel retinal acetylcholinesterase: inhibition by hexamethonium
J Enzyme Inhib 12 :303

Alhomida AS, Kamal MA, Al-Jafari AA (1997)
J Enzyme Inhib 12 :303