Acetylcholinesterase and Acetylcholine Receptor.

Our previous studies on cationic and uncharged substrates and reversible aliphatic and aromatic inhibitors led to the conclusions 1 that the subsite at which the trimethylammonio group of acetylcholine AcCh binds to acetylcholinesterase AcChE is not anionic but uncharged trimethyl in character 2 contiguous to it are aromatic aminoacid sidechains 3 the cationic and uncharged groups bind at the same site and 4 uncharged reagents would more specifically characterize the active site. Bromopinacolone, CH3 3CCOCH2Br BrPin , Kicom 0.2 mM, inactivated AcChE from Electrophorus with the same efficiency toward cationic and uncharged substrates. Acetylcholinesterase, Active Site, Label, Inhibitors, RA5.