Spijkerman (2011) reported on CCM regulation in the extremophilic

Spijkerman (2011) reported on CCM regulation in the extremophilic green alga, Chlamydomonas acidophila under extremely acidic conditions (pH 2.4) with changing phosphorous and iron concentrations and demonstrated that the size of the internal DIC pool was related to maximum photosynthesis, and became significantly higher with a high phosphorous quota. Primary production by marine eukaryotic algae has been shown to be a

vital part of global primary production as revealed by extensive biogeochemical research over the last one and half decades, aided by recent developments of the remote-sensing technique. Diatoms are a predominant component of the marine phytoplankton and have been estimated to be responsible for one-fifth of global primary production. CCMs appear to be distributed widely among Chromoalveolates, which is the super group of eukaryotes that arose from secondary endosymbiosis and which includes diatoms. The increased awareness of the importance of diatoms BMS-907351 concentration in the global carbon cycle has greatly stimulated studies of the ultra-structure and molecular biology of diatoms in the last decade. Matsuda et al. (2011) reviewed recent GF120918 concentration progress on CCM study in marine diatoms. There is a significant body of physiological evidence that both CO2 and HCO3 − are taken up by diatom cells p38 MAPK inhibitors clinical trials from the surrounding seawater,

but metabolic processes to deliver accumulated DIC to Rubisco is not clear and no molecular evidence exists at present. In this respect, it was proposed that CO2 acquisition by diatoms may SB-3CT have undergone a significant diversification including

the development of a C4-like system, which may also be related to a diversification of diatoms’ cell size (Matsuda et al. 2011). Molecular evidence of CAs localization strongly suggests that the function of the four-layered chloroplast membrane is the center of flow control of DIC. The Diatom CCM is also regulated by pCO2, and recent progress in molecular studies on the transcriptional control of CCM components in response to pCO2 have revealed that cAMP is a second messenger (Matsuda et al. 2011). There are redundant CA genes in genomes of two model marine diatoms, Phaeodactylum tricornutum, and Thalassiosira pseudonana (Tachibanal et al. 2011). In P. tricornutum, all 5 α-CAs were localized at the four-layered chloroplast membrane system whereas the 2 β-CAs were localized in the pyrenoid and one γ-CA in the mitochondria (Tachibanal et al. 2011), which provide a set of data to support the predominant operation of a biophysical CCM in P. tricornutum. In T. pseudonana, one α-CA and one ζ-CA were localized to the stroma and the periplasm, respectively and these CAs were induced under CO2 limitation (Tachibanal et al. 2011). Diatoms are also one of the most likely candidate sources for biofuels because of their capacity to produce high amounts of triacylglycerols (TAG) and hydrocarbons. A chloroplast genome was determined of a recently isolated pennate, marine diatom Fistulifers sp.

Comments are closed.