Picocystis Explained

Picocystis is a monotypic genus of green algae, the sole species is Picocystis salinarum. It is placed within its own class, Picocystophyceae in the division Chlorophyta.^[1]

Structure

Picocystis salinarum cells under normal conditions have a spherical or oval shape. Their size ranges from 2 to 3μm (micrometer, 10^-6) in diameter. Under conditions of nutrient depletion they appear to form a trillobe shape. This trillobe shape gives it the nickname Mickey Mouse, due to its appearance to the famous character's head. The general appearance resembles that of a standard green algae.

The pigments are composed mainly from chlorophyll a and b and the carotenoids violaxanthin, alloxanthin, monadoxanthin, neoxanthin, lutein, diatoxanthin and zeaxanthin.^[2]

The cell wall is mainly composed of polymers of the monosaccharide arabinose, polyarabinose.^[3]

Habitat

The species have been found in saline or hypersaline alkaline environments.^{[4] [5]}

Notes and References

1. Lopes Dos Santos A, Pollina T, Gourvil P, Corre E, Marie D, Garrido JL, Rodríguez F, Noël MH, Vaulot D, Eikrem W . Chloropicophyceae, a new class of picophytoplanktonic prasinophytes . Scientific Reports . 7 . 1 . 14019 . October 2017 . 29070840 . 5656628 . 10.1038/s41598-017-12412-5 . 2017NatSR...714019L .
2. Lopes Dos Santos A, Gourvil P, Rodríguez F, Garrido JL, Vaulot D . Photosynthetic pigments of oceanic Chlorophyta belonging to prasinophytes clade VII . Journal of Phycology . 52 . 1 . 148–55 . February 2016 . 26987097 . 10.1111/jpy.12376 . 10261/129034 . 3160723 . free .
3. Lewin RA, Krienitz L, Goericke R, Takeda H, Hepperle D . Picocystis salinarum gen. et sp nov (Chlorophyta) - a new picoplanktonic green alga. . Phycologia . 2000 . 39 . 6 . 560–565 . 10.2216/i0031-8884-39-6-560.1 . 83584521 .
4. Krienitz L, Bock C, Kotut K, Luo W . January 2012 . Picocystis salinarum (Chlorophyta) in saline lakes and hot springs of East Africa . Phycologia. en. 51. 1. 22–32. 10.2216/11-28.1 . 84149071 .
5. Ronald Oremland . Stamps BW, Nunn HS, Petryshyn VA, Oremland RS, Miller LG, Rosen MR, Bauer KW, Thompson KJ, Tookmanian EM, Waldeck AR, Loyd SJ, Johnson HA, Stevenson BS, Berelson WM, Corsetti FA, Spear JR . 6 . Metabolic Capability and Phylogenetic Diversity of Mono Lake during a Bloom of the Eukaryotic Phototroph Picocystis sp. Strain ML . Applied and Environmental Microbiology . 84 . 21 . November 2018 . 30120120 . 6193381 . 10.1128/AEM.01171-18 .