... clearly visible in the wild-type enzyme, in the A32 8Y mutant and in the ÔcompensatoryÕ mutant (Y3 32D/D7 0Y) . It can only be perceived in Y3 32A/D70Gmutant but is absent in the W82A and in horse enzyme. ... Twoamino-acid residues (D70 and Y3 32) in the PAS and two(W82 and A328) in the CS, known to play a role in thebinding of positively charged ligands and in inhibitioncontrol of BuChE, were selected. ... 0827–10831.17.Nachon,F.,Ehret-Sabatier,L.,Loew,D.,Colas,C.&vanDorsselaer and Goldner, M. (1998 ) Trp82 a nd Tyr332 a reinvolved in two quaternary a mmonium binding domains of human butyrylcholinesterase as revealed by photoaffinity labelingwith [3H]DDF....