Sandbox 1b41: Difference between revisions
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The catalytic site of AChE consists of two subsites: the "esteratic" site and "the anionic" site. (figure) | The catalytic site of AChE consists of two subsites: the "esteratic" site and "the anionic" site. (figure) | ||
In the <scene name='Sandbox_1b41/Esteratic_site/ | In the <scene name='Sandbox_1b41/Esteratic_site/2'>"esteratic site"</scene> a catalytic triad consisting of E334, H447, S203 forms a planar array that ressembles the catalytic triad of serine proteases. | ||
S203 is activated (it becomes nucleophilic) by E334 and H447. This activation allows the following reaction: the acylation between hydroxyl group of S203 and ACh oxygen (or other agonists). A covalent bond between the enzyme and the substrate creates an oxyanion. This oxyanion then reacts with two glycins setting up hydrogen bond. | S203 is activated (it becomes nucleophilic) by E334 and H447. This activation allows the following reaction: the acylation between hydroxyl group of S203 and ACh oxygen (or other agonists). A covalent bond between the enzyme and the substrate creates an oxyanion. This oxyanion then reacts with two glycins setting up hydrogen bond. | ||
In the "anionic" site, the W86 binds trimethylammonium group of ACh. | In the "anionic" site, the W86 binds trimethylammonium group of ACh. | ||
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Further to these steps the substrat is well positioned to be hydrolysed. | Further to these steps the substrat is well positioned to be hydrolysed. | ||
[[Image:Hydrolyse ACh par AChE.jpg| | [[Image:Hydrolyse ACh par AChE.jpg|frame|Captation]] | ||
