pyrenoid
Sign in to savethumb|270px|Cross section of a Chlamydomonas reinhardtii algae cell, a 3D representation
Article
9 sectionsContents
- Discovery
- Structure
- Gross morphology and ultrastructure
- Molecular components
- Role of pyrenoids in the CCM
- Physiology and regulation of the CCM
- Origin
- Diversity
- References
thumb|270px|Cross section of a Chlamydomonas reinhardtii algae cell, a 3D representation
Pyrenoids are sub-cellular phase-separated micro-compartments found in chloroplasts of many algae, and in a single group of land plants, the hornworts. Pyrenoids are associated with the operation of a carbon-concentrating mechanism (CCM). Their main function is to act as centres of carbon dioxide (CO2) fixation, by generating and maintaining a CO2-rich environment around the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). Pyrenoids therefore seem to have a role analogous to that of carboxysomes in cyanobacteria.