carbohydrate degradation plastidic glycolysis pathway In plants glycolysis occurs in both cytosol and plastids, with reactions in the different compartments catalysed by separate isoenzymes. In chloroplasts, glycolysis is most active in conjunction with the breakdown of starch to form sucrose for export to non-photosynthetic tissues. There is some doubt about the occurrence of phosphoglycerate mutase in chloroplasts, and therefore the main products of the glycolytic reactions may be triose phosphates and 3-PGA. These could be exported through the Pi translocator in the chloroplast envelope to the cytosol, where sucrose synthesis takes place. In photosynthetic cells, the triose phosphate exported to the cytosol for sucrose synthesis could also enter the glycolytic pathway directly to provide mitochondrial substrates. [http://plantsinaction.science.uq.edu.au/edition1/?q=content/2-4-2-glycolytic-pathway]. UPa:UPA01026