Modifications of cholinesterase enzymes and antiidiotypic mAb by
MCA-phosphonate. (A) Kinetics of interaction of
MCA-phosphonate (compound I) with BtChoEase (1) and AcChoE
(3) enzymes and with 9A8 (2) and IgM 2H11
(4) antibodies. Assays were performed on an Aminco
spectrofluorimeter (excitation, 365 nm, and emission, 450 nm). Protein
concentration was 55 nM, and substrate concentration was 1 μM in PBS,
pH 7.8. (B) Modification of 9A8 mAb H chain by compound II.
Protein concentration was 5.5 pM, and substrate concentration was 100
pM in PBS, pH 7.8. Western blot shown was stained by neutravidin-HRP
conjugate. Lanes: 1, 10-kDa molecular mass markers; 2, trypsin modified
by biotinylated 4-(2-aminoethyl)-benzenesulfonyl fluoride
(AEBSF); 3, 9A8 modified by biotinylated AEBSF; 4, monoclonal
IgM 2H11 modified by biotinylated AEBSF; 5, 9A8 modified by
compound II; 6, trypsin modified by compound II; 7, monoclonal IgM 2H11
modified by compound II.