Table 3.

Kinetic parameters of Rubisco from wheat (Triticum aestivum) and from the three C₄ grasses (Paspalum dilatatum, Cynodon dactylon, and Zoysia japonica) at 25 °C

Species	SC/O (VcKo/VoKc)	Kc (μM)	Ko (μM)	Vc (μmol min−1 mg−1 Rubisco)	Vo (μmol min−1 mg−1 Rubisco)
T. aestivum	100.0±9.2	10.9±0.9	341±33	2.54±0.07	0.79±0.03
P. dilatatum	88.0±7.1	19.9±0.8	415±5	3.11±0.04	0.71±0.03
C. dactylon	89.2±9.0	21.0±1.3	402±27	3.41±0.18	0.73±0.06
Z. japonica	84.1±7.7	18.5±1.2	403±27	3.78±0.08	0.98±0.08

For the Michaelis–Menten constants of Rubisco for CO₂ and O₂ (K_c and K_o, μM) and the maximum Rubisco carboxylation and oxygenation activities (V_c and V_o, μmol min⁻¹ mg⁻¹ Rubisco) the mean values and respective standard errors were calculated from measurements taken with three biological and three analytical replicates. The specificity factor (S_C/O) was determined in Rubisco purified from each species using a minimum of five analytical replicates.