Table 1.

Catalytic properties of esterolytic antibodies 9A8 and 17E8 and their recombinant Fabs

Catalyst	kcat, sec−1	KM, mM	kcat/Km × 103 M−1⋅s−1	Ref.
9A8	81	0.6	135	9
Recombinant 9A8 Fab	2.8	16.6	0.16
17E8	3.71	0.45	8.24	31
17E8 Fab	0.85	0.26	3.27	31
Recombinant hu17E8 Fab	0.98	0.58	1.69	38

Catalytic parameters of 9A8 and recombinant Fab fragment of 9A8 were determined by using acetylthiocholine as substrate. Catalytic parameters of 17E8, 17E8 Fab, and recombinant humanized 17E8 Fab (hu17E8) were obtained by using l-phenyl ester of N-formylnorleucine as described in refs. 31 and 38.