<Tr> <Td_colspan="2"> View / Edit Human </Td> <Td_colspan="2"> View / Edit Mouse </Td> </Tr> <P> Acetylcholinesterase (HGNC symbol ACHE), also known as AChE or acetylhydrolase, is the primary cholinesterase in the body . It is an enzyme that catalyzes the breakdown of acetylcholine and of some other choline esters that function as neurotransmitters . AChE is found at mainly neuromuscular junctions and in chemical synapses of the cholinergic type, where its activity serves to terminate synaptic transmission . It belongs to carboxylesterase family of enzymes . It is the primary target of inhibition by organophosphorus compounds such as nerve agents and pesticides . </P> <P> AChE is a hydrolase that hydrolyzes choline esters . It has a very high catalytic activity - each molecule of AChE degrades about 25000 molecules of acetylcholine (ACh) per second, approaching the limit allowed by diffusion of the substrate . The active site of AChE comprises 2 subsites - the anionic site and the esteratic subsite . The structure and mechanism of action of AChE have been elucidated from the crystal structure of the enzyme . </P> <P> The anionic subsite accommodates the positive quaternary amine of acetylcholine as well as other cationic substrates and inhibitors . The cationic substrates are not bound by a negatively charged amino acid in the anionic site, but by interaction of 14 aromatic residues that line the gorge leading to the active site . All 14 amino acids in the aromatic gorge are highly conserved across different species . Among the aromatic amino acids, tryptophan 84 is critical and its substitution with alanine results in a 3000-fold decrease in reactivity . The gorge penetrates halfway through the enzyme and is approximately 20 angstroms long . The active site is located 4 angstroms from the bottom of the molecule . </P>

What is the name of the enzyme that degrades ach
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