Conserved aromatic residues of the C-terminus of human butyrylcholinesterase mediate the association of tetramers

Research was conducted to examine the importance to human butyrylcholinesterase (BChE) tetramerization of seven selected conserved C-terminal aromatic residues, namely, Trp 543, Phe 547, Trp 550, Tyr 553, Trp 557, Phe 5661 and Tyr 564. Wild-type BChE C-terminal peptides interacted with one another independently from the remainder of the molecule in the yeast two-hybrid system. Results indicate that the conserved aromatic residues of the C-terminus are responsible for the stabilization of BChE tetramers and mediate the interactions to increase tetramers of BChE in the presence of poly-L-proline and the proline-rich attachment domain.