Pyrenoid

The pyrenoid is a spatially-limited, light microscopy often well recognizable structure in plastids of different groups of algae and hornworts, which mainly consists of paracrystalline RuBisCO, the key enzyme of photosynthesis. Since RuBisCO instead of carbon dioxide undesirably also highly oxygen in the ribulose -1 ,5 -bisphosphate installs ( photorespiration ), the organisms have developed various mechanisms to Kohlenstoffdioxidanreicherung to increase the efficiency of photosynthesis. Algae accumulate carbon dioxide locally in the pyrenoid, while higher plants have developed the C4 or CAM mechanism. The pyrenoid is thus a functional analog of carboxysomes in cyanobacteria.

The pyrenoid is also the deposition of reserve materials. For example, in the form of green algae, the starch granules to the pyrenoid around.

• Cell Biology