Amidohydrolase activity of MBP-CbiZ (expressed as nanomoles of Cby min-1 mg-1 protein) is shown. Error bars of one standard deviation are indicated. Unless indicated, reactions contained CHES buffer (50 mM, pH 10), DTT (1 mM), MBP-CbiZ (2 μg), and AdoCbi (30 μM) and were incubated for 15 min at 50°C.
A. Activity of MBP-CbiZ as a function of pH at 30°C. B. Activity of MBP-CbiZ as a function of temperature at pH 10. C. Activity of MBP-CbiZ as a function of time and enzyme concentration. D. Activity of MBP-CbiZ with different corrinoid substrates (30 μM). Reactions were incubated for 10 min.