Table 2-2: Some enzyme kinetic data for carbonic anhydrase

Author

CA source

Temp /C

kcat / s-1 x 103

Km / mM l-1

pH

Bundy (1986)

Chlamydomonas

0 44.8 3.1 7.3
Khalifah (1971) Human "C" 25 1400 (at pH 8.0)* 9 6.0 - 9.0
Sanyal and Maren (1981) Human "C" 0 236 (hydration)
66 (dehydration)
10 (hydration)
40 (dehydration)
7.5
Sanyal and Maren (1981) Human "C" 25 860 (hydration)
234 (dehydration)
12 (hydration)
47 (dehydration)
7.5
Kernohan (1965) Bovine 5   12 7.6
Pocker and Ng (1973) Spinach (hexamer?) 25 500 2 7.5
* For pH=6.0 the value for kcat is 10 times lower. There is little change between pH 8.0 and pH 9.0