Stimulation by abscisic acid of the activity of phosphoenolpyruvate carboxylase in leaf disks of Amaranthus hypochondriacus L., C plant: role of pH and protein levels.

C plants can more efficiently fix carbon in drought, high temperatures, and limitations of nitrogen or CO. Primary carboxylation is mediated by phosphoenolpyruvate carboxylase (PEPC, 4.1.