The reductive pentose phosphate cycle. III. Enzyme activities in cell-free extracts of photosynthetic organisms

Abstract

The en-zymes of the reductive pentose phosphate cycle were analyzed in extracts obtained from 3 photosynthesizing cells, namely, Chlorella, Euglena and spinach leaves. All enzymes of the cycle were found to be present but some activities were found to be very low. Particularly, transaldolase and hexosediphosphatase were far too low to satisfy the rate of CO2 fixation observed in intact cells.