Table 1.
PEPC K m-PEP values (pH 7.6) in representative species in subfamily Suaedoideae
Values were determined by curve-fitting the Hill equation to the data. Values represent the average of two biological and two technical replicates. The amino acid residues at positions 733 and 780, M (methionine), S (serine), L (leucine), A (alanine), F (phenylalanine), and V (valine) for the species are from Rosnow et al. (2014) and Besnard et al. (2003) for Z. mays.
| Species | Photosynthetic | Amino acid at | Amino acid | K m PEP (mM) | Hill coefficient (h) | Fold increase by G6P | ||
|---|---|---|---|---|---|---|---|---|
| mode | residue 733 | at residue 780 | No G6P | 5mM G6P | No G6P | +G6P | at 0.3mM PEP | |
| S. accuminata | Schoberia Kranz C4 | M | S | 0.83±0.12 | 0.10±0.01 | 2.61±0.12 | 1.13±0.19 | 4.3 |
| S. eltonica | Schoberia Kranz C4 | M | S | 1.04±0.14 | 0.14±0.02 | 2.71±0.24 | 0.90±0.08 | 2.7 |
| S. moquinii | Salsina Kranz C4 | L | A | 0.46±0.12 | 0.14±0.01 | 1.45±0.06 | 0.96±0.07 | 3.2 |
| S. fruticosa | Salsina Kranz C4 | L | A | 0.67±0.11 | 0.14±0.04 | 1.78±0.21 | 0.98±0.06 | 3.8 |
| S. aralocaspica | Single-Cell C4 | L | A | 0.74±0.08 | 0.14±0.02 | 2.13±0.22 | 0.90±0.03 | 2.7 |
| S. linearis | C3 | F | A | 0.21±0.01 | 0.03±0.01 | 1.19±0.15 | 1.29±0.25 | 2.3 |
| S. physophora | C3 | F | A | 0.27±0.02 | 0.05±0.01 | 0.94±0.15 | 0.93±0.11 | 2.1 |
| S. linifolia | C3 | F | A | 0.35±0.03 | 0.04±0.01 | 0.95±0.02 | 0.90±0.07 | 2.6 |
| Zea mays | C4 | V | S | 1.23±0.07 | 0.15±0.08 | 1.18±0.01 | 1.17±0.07 | 5.0 |