Figure 3.

Analysis of Rubisco interactions with variants of Rca. Included in the analyses were recombinant TaRca2-α, TaRca2-β, TaRca1-β, and OsRca-β. A, Rubisco activation velocity by Rca at 25°C. Experiments consisted of 1.6 ± 0.2 μm Rca protomer added to 0.2 ± 0.05 μm Rubisco active sites inhibited by RuBP (ER). B, Temperature-dependent Rubisco activation by Rca. Rca was incubated for 10 min in the presence of 0.2 mm ATP at the indicated temperatures prior to assaying at a standard 25°C, and values are normalized to the fastest velocity achieved. C, DSF. Samples were heated at 1°C min⁻¹, and fluorescence units (FU) normalized to the maximum value were recorded. Values are means ± sd of four experimental replicates. Curves are the ordinary least-squares fit of a Boltzmann sigmoidal equation (Eq. 1). The calculated initial V₂₅ and T_m are presented in Table 1.