Low active isoenzyme

Lindskog et al. (142) first reported that the catalytic activities of CAI and II are controlled by an ionizing active-site group with a pifa 7 under experimental conditions. The hydration of CO2 with turnover number of 1 x 10 s (pH 9, 25°C) (149,150), 2x 10 s (pH 9, 25°C) (149), and 4x10 s (pH 7.5, 25 °C) (151) has been reported for high activity isoenzyme CAH, less active isoenzyme CAI, and very low active isoenzyme CAHI, respectively (see Table IV). 

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