Fig. 6

Reaction velocity measurements of R. eutropha form I RubisCO as a function of CO₂ concentration in the presence (open circles) or absence (closed circles) of saturating levels of oxygen (i.e., 1230 μM). a Michaelis–Menten curves for carboxylation activities measured with unbound R. eutropha form I RubisCO. b Michaelis–Menten curves for carboxylation activities measured with nanotube B-form I RubisCO complexes. The extent of oxygen inhibition for each enzyme preparation is indicated (double-headed arrows). The K _O (K _I) for O₂ was enhanced about 1.6-fold for the nanotube B-form I enzyme complex compared to the unbound enzyme (see Table 3 for kinetic constants). The average value and error bar for each data point was calculated with values obtained from two independent assays (with different preparations) performed with identical CO₂ concentrations