Dependence of the CO2 assimilation rate on the
intracellular CO2 concentration (Ci) in the wild type
(●), rca mutant (⋄), and
rca transformants expressing either the 43-kDa
(▵) or 46-kDa (□) isoform of activase. The
calculated initial slopes were as follows: WT, 0.061; 43-kDa, 0.054;
46-kDa, 0.040; and rca, 0.01.