Table I. Validation of enzyme parameters determined by parameter estimation.
Values of Km and Ki are given in mm. The unit of maximum enzyme activity (Vmax) is μmol h−1 g−1 fresh weight. F6P, Fru-6-P; FrcK, fructokinase; G6P, Glc-6-P; GlcK, glucokinase; Inv, invertase.
| Reaction | Parameter | Genotype | Parameter Estimation | Experimental Data | Literature Values |
||
| Value | Species | Reference | |||||
| rSP→Suc (SPS) | Vmax (5 am) | Col-0 | 0.4 ± 0.2 | 3.7 ± 3.6 | 32.4 | Arabidopsis | Gibon et al. (2004a) |
| inv4 | 3.9 ± 6.8 | 5.5 ± 0.9 | |||||
| Vmax (1 pm) | Col-0 | 27.1 ± 1.4 | 30.2 ± 5.1 | ||||
| inv4 | 21.9 ± 1.0 | 23.8 ± 4.0 | |||||
| Vmax (9 pm) | Col-0 | 12.2 ± 1.3 | 9.6 ± 4.1 | ||||
| inv4 | 12.3 ± 1.3 | 8.8 ± 2.9 | |||||
| Km | Col-0 | 0.53 ± 0.082 | – | 0.7–0.8 | Spinacia oleracea | Harbron et al. (1981) | |
| inv4 | |||||||
| rSuc→Hex (Inv) | Vmax (5 am) | Col-0 | 68.0 ± 6.9 | 59.3 ± 18.4 | 60 | Arabidopsis | Klotke et al. (2004) |
| inv4 | 11.0 ± 0.001 | 7.9 ± 3.2 | |||||
| Vmax (1 pm) | Col-0 | 155.5 ± 12.0 | 137.0 ± 29.0 | ||||
| inv4 | 12.9 ± 0.2 | 8.6 ± 4.9 | 30,000 | Tang et al. (1996) | |||
| Vmax (9 pm) | Col-0 | 99.9 ± 7.5 | 114.7 ± 20.6 | ||||
| inv4 | 17.0 ± 1.8 | 15.6 ± 4.3 | |||||
| Km | Col-0 | 11.7 ± 1.21 | – | 5–12 | Arabidopsis | Tang et al. (1996) | |
| inv4 | |||||||
| Ki,Glc | Col-0 | 0.01 ± 0.001 | – | – | – | – | |
| inv4 | |||||||
| Ki,Fru | Col-0 | 0.78 ± 2.29 | – | 2.5 | Lolium temulentum | Kingston-Smith et al. (1999) | |
| inv4 | |||||||
| rFru→SP (FrcK) | Vmax (5 am) | Col-0 | 4.1 ± 0.5 | 4.61 ± 1.31 | 5.0 ± 0.5 | Arabidopsis | Moore et al. (2003) |
| inv4 | 4.9 ± 1.6 | 5.0 ± 0.4 | |||||
| Vmax (1 pm) | Col-0 | 3.6 ± 0.6 | 4.0 ± 0.8 | ||||
| inv4 | 4.4 ± 1.2 | 3.1 ± 0.8 | |||||
| Vmax (9 pm) | Col-0 | 8.0 ± 1.3 | 9.2 ± 0.4 | ||||
| inv4 | 8.8 ± 2.6 | 7.8 ± 1.9 | |||||
| Km | Col-0 | 0.8 ± 0.075 | – | 1.5–30 | S. oleracea | Claeyssen and Rivoal (2007) | |
| inv4 | |||||||
| Ki,F6P | Col-0 | 1.97 ± 0.31 | – | – | – | – | |
| inv4 | |||||||
| rGlc→SP (GlcK) | Vmax (5 am) | Col-0 | 4.8 ± 0.9 | 4.8 ± 1.3 | 3.8 ± 0.2 | Arabidopsis | Moore et al. (2003) |
| inv4 | 4.5 ± 1.5 | 4.1 ± 0.4 | |||||
| Vmax (1 pm) | Col-0 | 6.2 ± 1.7 | 3.4 ± 1.6 | ||||
| inv4 | 5.2 ± 1.5 | 3.8 ± 0.1 | |||||
| Vmax (9 pm) | Col-0 | 12.9 ± 2.8 | 10.1 ± 1.9 | ||||
| inv4 | 7.9 ± 2.4 | 8.6 ± 0.4 | |||||
| Km | Col-0 | 0.1 ± 0.02 | – | 0.02–0.13 | S. oleracea | Claeyssen and Rivoal (2007) | |
| inv4 | |||||||
| Ki,G6P | Col-0 | 0.14 ± 0.03 | – | No effect | Pisum sativum | Claeyssen and Rivoal (2007) | |
| inv4 | Weak effect | Zea mays | |||||