title: A novel class of acetylcholinesterase, revealed by mutations, in the nematode Caenorhabditis elegans.
abstract: In ace-2;ace-1 double mutants of the nematode C. elegans, where the major acetylcholinesterase (AChE) classes A and B have been eliminated by mutation, the animals are viable and residual AChE activity remains. This residual activity differs markedly from AChE classes A and B; its Km for acetylcholine is 1000-5000-fold lower, its resistance to eserine is 3000-260,000-fold higher, it is markedly more thermolabile, and it can be separated from classes A and B by ion exchange chromatography. It has been designated class C AChE. Class C AChE of indistinguishable properties is also present in wild type C. elegans, at levels approximating those seen in ace-2;ace-1 double mutants, suggesting that it is controlled by a third, as yet unidentified, gene. Amongst other sources examined, class C-like AChE has been detected in another nematode species, Stephanurus dentatus, but not in Drosophila melanogaster, Torpedo californica, or Rattus rattus.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000110:Acetylcholinesterase / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D000483:Alleles; D000818:Animals; D002107:Caenorhabditis / Q000201:enzymology* / Q000235:genetics; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D006358:Hot Temperature; D007700:Kinetics; D009154:Mutation; D011489:Protein Denaturation; D051381:Rats
chemical_list: D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase; D000109:Acetylcholine