Espèces acétylcholinestérasiques globulaires et allongées des organes électriques de poissons

Abstract

In the present communication we show that species A, C, D of both Torpedo and Electric eel acetylcholinesterase are totally excluded from Sephadex G‐200 and Biogel P‐300 molecular sieves. These “native” species do not enter polyacrylamide gels (7.5%) and are disrupted by sonication. Considering their sedimentation constant, this is only compatible with extremely elongated structures. Another class of acetylcholinesterase species behave like normal globular proteins; we therefore denote them G: purified enzyme (Gp: 11.1 S), tryptic enzyme (Gt: 11.8 S), and another species obtained from A after sonication (G's: 7.7 S). The relationships of A with Gt and G's are discussed, as well as the possible significance of an asymmetric structure for a membrane‐bound enzyme.