Acetylcholinesterase of the house-fly head. Affinity purification and subunit composition.
1. Acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7) of house-fly head tissue was solubilized as a 7.4-S form by autolysis for 80-100 h at 25 degrees C and pH 8.0. 2. The autolysed enzyme was purified by affinity chromatography, firstly on Con-A-Sepharose and subsequently on m-trimethylammoniumaniline-Affi-Gel 202. This sequence permitted overall purification yields of approx. 50% of the solubilized enzyme. 3. The 7.4-S purified enzyme was essentially homogeneous on polyacrylamide gel electrophoresis, and its specific activity coincided with the highest previously reported for fly-head acetylcholinesterase. 4. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate and beta-mercaptoethanol revealed two major polypeptide components of molecular weight 82 000 and 59 000. Each of these polypeptides contained diisopropylphosphofluoridate-binding sites, as shown with [3H] diisopropylphosphofluoridate. 5. The results suggest a strong structural similarity between fly-head acetylcholinesterase and the purified electric eel enzyme.
D000110:Acetylcholinesterase / Q000302:isolation & purification*; D001665:Binding Sites; D002846:Chromatography, Affinity; D006257:Head / Q000201:enzymology; D006793:Houseflies / Q000201:enzymology*; D008024:Ligands; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D011485:Protein Binding
D008024:Ligands; D010446:Peptide Fragments; D000110:Acetylcholinesterase