Table 1.

Kinetic constants for inactivation of AChE^a, and for hydrolysis of compounds 1-16 using mutants of phosphotriesterase.^b

Compound	Inactivation rate constant kinact/KI, (M−1 min−1)	wild-type	G60A	YT kcat/Km (M−1 s−1)	BHR-30	BHR-72
(SP)-1	(1.4 × 10⁷)c	3.7 × 105	4.7 × 104	5.8 × 106	2.4 × 106	3.9 × 105
(RP)-1		3.7 × 105	3.5 × 105	<1 × 104	2.4 × 106	2.6 × 106
(SP)-2	2.8 × 103	1.7 × 104	<1 × 102	4.8 × 104	4.0 × 104	3.6 × 104
(RP)-2		2.5 × 105	5.6 × 105	4.8 × 104	4.0 × 104	3.6 × 104
(RP)-3	1.0 × 104	1.7 × 106	2.6 × 105	1.4 × 106	4.7 × 106	1.7 × 106
(SP)-3		1.7 × 106	5.7 × 106	1.2 × 105	4.7 × 106	1.7 × 106
(SP)-4	1.8 × 102	2.2 × 104	<1 × 103	2.0 × 104	1.6 × 104	4.1 × 104
(RP)-4		4.3 × 105	1.8 × 106	2.0 × 104	6.0 × 104	4.1 × 104
(SP)-5	4.4 × 103	4.8 × 105	3.0 × 104	8.1 × 105	4.9 × 105	3.6 × 105
(RP)-5		6.0 × 106	4.2 × 106	9.0 × 104	4.9 × 105	3.6 × 105
(SP)-6	NOd	1.9 × 105	1.6 × 103	2.0 × 105	4.5 × 104	1.8 × 105
(RP)-6		1.3 × 107	2.0 × 107	2.0 × 105	2.9 × 105	1.8 × 105
(RP)-7	1.2 × 103	1.1 × 106	1.4 × 105	1.1 × 106	3.9 × 105	4.7 × 105
(SP)-7		3.1 × 107	5.6 × 107	1.1 × 106	8.7 × 106	3.8 × 106
(SP)-8	NO	6.3 × 104	<1 × 103	2.8 × 104	3.5 × 104	5.6 × 104
(RP)-8		2.2 × 107	4.0 × 107	2.8 × 104	2.4 × 106	3.6 × 105
(SP)-9	(2.6 × 10⁸)c	<1 × 104	<1 × 103	5.4 × 105	1.2 × 105	<1 × 10³
(RP)-9		1.2 × 106	8.8 × 10⁵	<1 × 10³	1.3 × 106	3.0 × 105
(SP)-10	3.2 × 103	<1 × 102	<1 ×102	9.5 × 102	<1.5 × 102	4.0 × 103
(RP)-10		1.9 × 105	2.2 × 105	9.4 × 103	1.1 × 105	2.8 × 104
(RP)-11	3.0 × 105	4.8 × 103	<1 × 103	3.9 × 105	3.3 × 104	1.4 × 105
(SP)-11		2.1 × 106	2.9 × 106	3.9 × 105	6.0 × 106	1.8 × 106
(SP)-12	3.1 × 103	4.6 × 102	<1 × 103	<1 × 102	1.1 × 103	4.2 × 103
(RP)-12		2.6 × 105	5.3 × 105	8.4 × 103	2.0 × 105	1.2 × 105
(SP)-13	5.1 X 104	4.6 × 102	<6 × 102	1.7 × 105	8.8 × 102	4.5 × 104
(RP)-13		3.7 × 106	3.0 × 106	1.7 × 105	9.9 × 105	4.0 × 105
(SP)-14	NO	<2 × 102	<6 × 102	2.6 × 103	<2 × 102	3.8 × 103
(RP)-14		3.6 × 105	6.0 × 105	2.7 × 104	1.7 × 105	1.0 × 105
(RP)-15	8.7 × 103	1.4 × 106	<1 × 103	6.1 × 104	1.2 × 104	4.8 × 104
(SP)-15		1.7 × 107	1.9 × 107	2.3 × 105	6.3 × 106	4.1 × 106
(SP)-16	4.4 × 102	< 2 × 10²	<1 × 103	<1 × 10²	<2 × 102	9.7 × 103
(RP)-16		1.2 × 106	1.5 × 106	3.0 × 103	2.7 × 105	5.7 × 104

^apH 8.0 and 25 °C.

^bkpH 9.0 and 30 °C.

^creferences 5 and 7.

^dNO, not observed.