Dictionary > Carboxysome

Carboxysome

Carboxysome is a protein-shell micro-compartment inside bacterial cell and is involved chiefly in carbon fixation. It is a cytoplasmic proteinaceous structure in the cytosol of bacteria such as Cyanobacteria and other CO2-fixing bacteria. It is made up of polyhedral protein shells of 80-140 nm in diameter. It contains enzymes (e.g. ribulose-1,5-biphosphate carboxylase/oxygenase or RubisCO) involved in carbon fixation. Its function is to ensure that there is an adequate concentration of carbon dioxide (CO2) for fixation. It concentrates carbon dioxide inside through co-localized carbonic anhydrase activity that produces CO2 from bicarbonate. The protein shell of the carboxysome prevents the escape of CO2. Having sufficient CO2 near RuBisCO inside the carboxysome warrants carbon fixation and prevents too much photorespiration. Apart from carboxysome, other organellar-like structures in prokaryotes are chlorosome and magnetosome.

See also

References

  1. 4.6C: Carboxysomes. (2019, June 5). Retrieved from Biology LibreTexts website: https://bio.libretexts.org/Bookshelves/Microbiology/Book%3A_Microbiology_(Boundless)/4%3A_Cell_Structure_of_Bacteria%2C_Archaea%2C_and_Eukaryotes/4.6%3A_Specialized_Internal_Structures_of_Prokaryotes/4.6C%3A_Carboxysomes

© Biology Online. Content provided and moderated by Biology Online Editors



You will also like...

Freshwater Ecology
Freshwater Ecology

Freshwater ecology focuses on the relations of aquatic organisms to their freshwater habitats. There are two forms of co..

Chromosomes X and Y and Sex Determination
Chromosomes X and Y and Sex Determination

This tutorial looks at sex determination via the sex chromosomes, X and Y. Read it to get more info on X and Y chromosom..

Population Regulation in an Ecosystem
Population Regulation in an Ecosystem

With regard to the population size of a species and what factors may affect them, two factors have been defined. They ar..

Salmon jumping upstream in the river
Lotic Communities & Animals

A running water environment offers numerous microhabitats for many types of animals. Similar to plants, animals in lotic..

Chemical effects on plant growth and development
Effect of Chemicals on Growth & Development in Organisms

Plants and animals need elements, such as nitrogen, phosphorus, potassium, and magnesium for proper growth and developme..

Digestion and Absorption of Food
Digestion and Absorption of Food

The gastrointestinal system breaks down particles of ingested food into molecular forms by enzymes through digestion and..

Related Articles...

No related articles found

See all Related Topics