Acta Parasitologica, Vol. 50, No. 4, 2005, 344-351 Tadeusz Moczon* and Agnieszka Swietlikowska - Acetylcholinesterase from mature Hymenolepis diminuta (Cestoda)
W. Stefanski Institute of Parasitology, Polish Academy of Sciences, 51/55 Twarda Street, 00-818 Warszawa, Poland
*Corresponding author: moczon@twarda.pan.pl
ABSTRACT
Acetylcholinesterase (AChE) sequentially extracted from mature specimens of Hymenolepis diminuta was shown to be a globular protein, the monomeric form of which (Ga
1) had molecular mass of 66 kDa as determined by SDS-PAGE. Amphiphilic character
of the enzyme was revealed by Triton X-114 phase partitioning. The cestode AChE preferred acetylthiocholine over propionyl- and butyrylthiocholine as substrate, split N-acetyl-beta-methylthiocholine and myristoylcholine but did not hydrolyze beta-carbonaphthoxycholine, a substrate for butyrylcholinesterases. It was sensitive to 10-5 M physostigmine and 10-5 M BW284C51 but not to 10-3 M iso-OMPA. No butyrylcholinesterase activity was detected in extracts from the parasite.
KEY WORDS: Hymenolepis diminuta, biochemistry, acetylcholinesterase, electrophoresis, phase partitioning