Raven, John A.; Cockell, Charles S. and De La Rocha, Christina L.
|DOI (Digital Object Identifier) Link:||http://doi.org/10.1098/rstb.2008.0020|
|Google Scholar:||Look up in Google Scholar|
Inorganic carbon concentrating mechanisms (CCMs) catalyse the accumulation of CO2 around rubisco in all cyanobacteria, most algae and aquatic plants and in C4 and crassulacean acid metabolism (CAM) vascular plants. CCMs are polyphyletic (more than one evolutionary origin) and involve active transport of HCO-3, CO2 and/or H+, or an energized biochemical mechanism as in C4 and CAM plants. While the CCM in almost all C4 plants and many CAM plants is constitutive, many CCMs show acclimatory responses to variations in the supply of not only CO2 but also photosynthetically active radiation, nitrogen, phosphorus and iron. The evolution of CCMs is generally considered in the context of decreased CO2 availability, with only a secondary role for increasing O2. However, the earliest CCMs may have evolved in oxygenic cyanobacteria before the atmosphere became oxygenated in stromatolites with diffusion barriers around the cells related to UV screening. This would decrease CO2 availability to cells and increase the O2 concentration within them, inhibiting rubisco and generating reactive oxygen species, including O3.
|Item Type:||Journal Article|
|Copyright Holders:||2008 The Royal Society|
|Extra Information:||One contribution of 15 to a Discussion Meeting Issue ‘Photosynthetic and atmospheric evolution’.|
|Keywords:||alga; cyanobacteria; crassulacean acid metabolism; C4 photosynthesis; embryophytes; stromatolites|
|Academic Unit/Department:||Science > Physical Sciences
|Interdisciplinary Research Centre:||Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)|
|Depositing User:||Charles Cockell|
|Date Deposited:||26 Jan 2011 12:02|
|Last Modified:||18 Jan 2016 09:40|
|Share this page:|