Hatch-Slack-Kortshak pathway

(= Hatch-Slack pathway)

Metabolic pathway responsible for primary CO2 fixation in C4 plant photosynthesis. The enzymes that are found in mesophyll chloroplasts include PEP carboxylase, that adds CO2to phosphoenolpyruvate to give the 4-carbon compound, oxaloacetate. Four-carbon compounds are transferred to bundle-sheath chloroplasts, where the CO2 is liberated and re-fixed by the Calvin-Benson cycle. The HSK pathway permits efficient photosynthesis under conditions of high light intensity and low CO2 concentration, avoiding the non-productive effects of photorespiration.