title: Secretory acetylcholinesterases from Brugia malayi adult and microfilarial parasites.
abstract: Brugia malayi, a lymphatic filarial parasite, secretes acetylcholinesterase during in vitro cultivation. A significant amount of enzyme activity was detected both in culture media and somatic extracts of adult and microfilarial stages of the parasite. The microfilarial stage produces three times more enzyme than adult parasites as a proportion of total protein. The enzyme has true acetylcholinesterase (AChE) activity as hydrolysis of acetylthiocholine is three times faster than butyrylthiocholine and is inhibited by eserine, a specific inhibitor of AChE. Secretory enzyme from adult female parasite excretory-secretory material (ES) was enriched 23 fold using copper chelating and concanavalin A (Con A) affinity chromatography. The Con A eluate showed a major protein band of 100 kDa and a minor 200 kDa component. The ES enzyme is antigenic and cross reacts with antibodies raised in mice against AChE from electric eel by enzyme-linked immunosorbent assay and immunoprecipitation. Immunoprecipitation of 125I-labelled microfilarial ES and adult ES with anti-electric eel AChE antibodies revealed three proteins of 30, 40 and 200 kDa in microfilariae and two proteins of 100 and 200 kDa in adult female ES. It appears that filarial secretory AChE exists in multiple molecular forms.
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D002009:Brugia / Q000201:enzymology*; D003429:Cross Reactions; D004492:Edetic Acid; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D007120:Immunochemistry
chemical_list: D004492:Edetic Acid; D000110:Acetylcholinesterase