Molecular Structures of Acetylcholinesterase from Electric Organ Tissue of the Electric Eel

作者：Yadin Dudai, Max J. Herzberg, Israel Silman · 发表于：Proceedings of the National Academy of Sciences · 年份：1973 · DOI：10.1073/pnas.70.9.2473 · 被引用次数：109 · 研究领域：Cholinesterase and Neurodegenerative Diseases、thermodynamics and calorimetric analyses、Neurobiology and Insect Physiology Research

Three purified molecular forms of acetylcholinesterase (EC 3.1.1.7) with sedimentation coefficients of 18 S, 14 S, and 11 S were studied by analytical ultracentrifugation and electron microscopy. The three species have molecular weights of (1.1 +/- 0.1) x 10(6), (7.5 +/- 1.5) x 10(5), and (3.35 +/- 0.25) x 10(5), respectively. Electron micrographs reveal that the 18S and 14S forms are asymmetric, composed of a head, containing a large number of subunits, and an elongated tail. The 11S form of acetylcholinesterase is apparently a tetrameric structure devoid of the tail. Maleylation of 18S and 14S acetylcholinesterases abolishes their tendency to aggregate at low ionic strength.