An enzyme in the carboxylases responsible for the formation of the four-carbon compound oxaloacetate by catalyzing the binding of one molecule of carbon dioxide to the three-carbon compound phosphoenolpyruvate.
PEP carboxylase is vital in CAM and C4 plants during photosynthesis. It serves as the catalyst for the following chemical reaction:
PEP + CO2 → oxaloacetate + Pi
Word origin: from the abbreviation of phosphoenolpyruvate carboxylase
Variant: PEPC, PEPCase
See also: CAM plant, C4 plant