Table I.

Impact of Trypsin Residue 39 on Inhibition by BPTI and APPI

Enzymes compared	Inhibitor	Ki (M) (S39)	Ki (M) (Y39)	Fold diff.	ΔΔGa° (kcal/mol)
Cationic-Y39S/Cationic-wt	BPTI	1.1 ± 0.3 × 10−10	2.0 ± 0.3 × 10−11a	5.5	−1.04
Mesotrypsin-wt/Mesotrypsin-S39Y	BPTI	1.4 ± 0.3 × 10−5 a	2.7 ± 0.4 × 10−6	5.1	−1.00
Cationic-Y39S/Cationic-wt	APPI	7.5 ± 1.3 × 10−10	1.7 ± 0.3 × 10−10b	4.4	−0.91
Mesotrypsin-wt/Mesotrypsin-S39Y	APPI	1.4 ± 0.2 × 10−7b	1.1 ± 0.3 × 10−8	12.5	−1.55

^aValues previously reported in Ref.10.

^bValues previously reported in Ref.11.