Fig. 4.
Determination of the KM value for formate and H2. a Methylviologen-dependent hydrogenase activity was measured with H2 as electron donor and methylviologen (10 mM) as electron acceptor in 1 ml buffer (100 mM HEPES/NaOH, 2 mM DTE, pH 7.0) and a gas phase of N2 and varying amounts of H2 at a pressure of 1.1 × 105 Pa. b Methylviologen-dependent formate dehydrogenase activity was measured as described for a except that the gas phase was 100% N2 and varying concentrations of formate were used as electron donor