Prasinophyceae

Taxobox
name = Prasinophyceae
domain = Eukaryota
regnum = Plantae
divisio = Chlorophyta
classis = Prasinophyceae
subdivision_ranks = Orderscite web | url = http://www.algaebase.org/browse/taxonomy/?id=4345 | publisher = "AlgaeBase version 4.2" World-wide electronic publication, National University of Ireland, Galway | accessdate = 2007-09-23 | title = Class: Prasinophyceae taxonomy browser | author = Guiry, M.D. & Guiry, G.M. | year = 2007 ]
subdivision =
* Chlorodendrales
* Mamiellales
* Nephroselmidales
* Prasinococcales
* Pseudoscourfieldiales
* Pyramimonadales

In taxonomy, Prasinophytes are a class of primitive eukaryotic, marine green algae. [cite journal | author = Sym SD, Pienaar RN | year = 1993 | title = The class Prasinophyceae | journal = Prog Phycol Res | volume = 9 | pages = 281–376] Its best known genus is "Ostreococcus", which is considered to be the smallest (ca. 0.95 μm) free-living eukaryote [cite journal | author = Courties C, Vaquer A, Troussellier M, Lautier J, Chrétiennot-Dinet MJ, Neveux J, Machado C, Claustre H | year = 1994 | title = Smallest eukaryotic organism | journal = Nature | volume = 370 | pages = 255 | doi = 10.1038/370255a0] and which has been detected in marine samples around the world. Prasinophytes are thought to have low cellular complexity i.e. they are naked cells that possess single, multiple or no flagellae and contain only a single chloroplast and a single mitochondrion. They also have very small genomes for a eukaryote (about 12Mbp).

Ecology

A study of photosynthetic gene-sequence diversity ("rbcL") in the Gulf of Mexico indicated that Prasinophytes are particularly prevalent at the Subsurface Chlorophyll Maximum (SCM) [cite journal | author = Wawrik B, Paul JH, Campbell L, Griffin D, Houchin L, Fuentes-Ortega A, Müller-Karger F | year = 2003 | title = Vertical Structure of the Phytoplankton Community Associated with a Coastal Plume in the Gulf of Mexico | journal = Marine Ecology Progress Series | volume = 251 | pages = 87–101 | doi = 10.3354/meps251087] and several different ecotypes of "Ostreococcus" have been detected in the environment. [cite journal | author = Guillou L, Eikrem W, Chrétiennot-Dinnet MJ, Le Gall F, Massana R, Romari K, Pedros-Alio C, Vaulot D | year = 2004 | title = Diversity of picoplanktonic Prasinophyceae assessed by direct SSU rDNA sequencing of environmental samples and novel isolates retrieved from oceanic and coastal marine ecosystems | journal = Protist | volume = 155 | pages = 193–214 | doi = 10.1078/143446104774199592] These ecotypes are distinguished by their adaptation to light intensities. "O. lucimarinus" is found in high-light environments and represents surface-isolated strains. RCC141 is considered low-light, because these strains were isolated from the lower euphotic zone. "O. tauri" was isolated from a coastal lagoon and is considered light-polyvalent. Genetic data indicates that distinct molecular differences exist between the different ecotypes that have been detected. [cite journal | author = Rodríguez F, Derelle E, Guillou L, Le Gall F, Vaulot D, Moreau H| year = 2005 | title = Ecotype diversity in the marine picoeukaryote Ostreococcus (Chlorophyta, Prasinophyceae) | journal = Environmental Microbiology | volume = 7 | pages = 853–859 | doi = 10.1111/j.1462-2920.2005.00758.x ]

References

External links

Links to scientific references

Links to scientific databases