Fig. 6
A convergent change in phosphoenolpyruvate carboxylase (PEPC) protein sequences in CAM species. a convergent- vs. divergent-substitutions in PEPC2 protein sequences between species listed in Supplementary Table 9. The arrow head indicates the comparison of K. fedtschenkoi vs. P. equestris. b Probability of convergent changes in PEPC2 protein sequence between K. fedtschenkoi and orchid. Red arrow indicates the protein sequence alignment site of convergent change (highlighted in red font at the alignment in panel c). c A convergent amino-acid change (from R/K/H to D) in PEPC2 shared by diverse species (highlighted in red font) at the alignment position indicated by the red arrow. d In vitro activity of PEPC isoforms in the absence of phosphorylation by PPCK. KfPEPC1: Kaladp0095s0055; KfPEPC1R515D: KfPEPC1 with mutation at residue 515 from arginine (R) to aspartic acid (D); KfPEPC2: Kaladp0048s0578.1; KfPEPC2D509K: KfPEPC2 with mutation at residue 509 from D to lysine (K); PqPEPC2: P. equestris PEPC gene PEQU07008; PqPEPC2D504K: PqPEPC2 with mutation at residue 504 from D to K. “*” indicates significant difference between wild-type and mutant of PEPC1 or PEPC2 (Student’s t-test; P < 0.01). The error bars indicate standard deviation (SD) calculated from three replicates
