Dictyochloropsis
From Wikipedia, the free encyclopedia
| Dictyochloropsis | |
|---|---|
Scientific classification  | |
| Kingdom: | Plantae |
| Division: | Chlorophyta |
| Class: | Trebouxiophyceae |
| Order: | Trebouxiales |
| Family: | Trebouxiaceae |
| Genus: | Dictyochloropsis Geitler (1966) |
| Species | |
Dictyochloropsis /ˌdɪktioʊˌklɔɹˈɑpsɪs/ is a genus of unicellular green alga of the phylum Chlorophyta. This genus consists of free-living algae which have a reticulate (net-like) chloroplast that varies slightly in morphology between species,[1][2][3] and that when mature always lacks a pyrenoid.[3] Dictyochloropsis is asexual and reproduces using autospores.[1]
Previously, many species of the morphologically similar genus Symbiochloris were incorrectly classified to this taxon. These species were recently reclassified on the basis of molecular DNA analyses.[3]
Dictyochloropsis is found in terrestrial environments all over the world,[2][4][5][6][7][8] but can live and grow in freshwater environments as well.[1][4] Recently, there has been promising research towards growing Dictyocloropsis in culture for the production of biofuels.[4]
The name of Dictyochloropsis comes from the Greek language, and references the similar algal genus Dictyochloris. The suffix “-opsis” comes from “ὄψις” or “opsis”, roughly translating to “appearance,” “sight” or “view”.[9] Therefore, “Dictyochloropsis” when translated from its Greek roots means “Dictyochloris-like”. In turn, the prefix “dictyo” is derived from the Greek word “δίκτυο” or “díktyo” meaning “network”,[10] which is in reference to the net-like chloroplast present in this genus and Dictyochloropsis. The medial “-chloro-” is from “χλωρός” or “chloros” meaning “the colour green”[11][12] because of the green pigment, chlorophyll, which colours the algae.
History of knowledge
Dictyochloropsis was first identified as a genus in 1966 by Lothar Geitler, who defined it as a unicellular green algae with a complex chloroplast that reproduces using autospores. Geitler’s observations were not complete, he was unsure if he had correctly defined the new genus, and he requested supplementary observations from other scientists to attempt at further defining the taxon.[13]
In the early 1980s, Elisabeth Tschermak-Woess used Geitler’s definition to classify several species of lichenized green algae under the same taxon. However, some of these algae reproduce with zoospores or aplanospores,[7][14] which does not agree with Geitler’s observations.[3][13]
In 2014, Francesco Dal Grande used microsatellite markers to discover that Dictyochloropsis as previously defined was polyphyletic, forming two distinct clades. The first clade is composed exclusively of free-living algae which reproduce using autospores.[2] The second clade included lichenized as well as free-living algae that reproduce using zoospores or aplanospores.[2] Organisms in both clades have similar morphologies and life cycles,[1][3][7][8][14] and this is why they were initially classified in this polyphyletic genus.[3]
In 2016, Pavel Skaloud et al. moved the Dictyochloropsis lichenized species to the genus Symbiochloris based on data from phylogenetic analysis of the 18S rRNA gene.[3] As a result Dictyochloropsis was redefined to its current monophyletic meaning.[3]
Habitat and ecology
Dictyochloropsis is an ecologically important algae[2] most commonly found living as an epiphyte or in soil. Although species in the phylum Chlorophyta mainly live in freshwater habitats,[15] Dictyochloropsis is usually found in terrestrial environments.[1][2][3][4][7][8][13][14] This algae does not feed, it uses photosynthesis to create its energy, and thus it only lives in habitats with access to light.[15]
Species have been found and cultured from places all over the world, including the Czech Republic, Malaysia,[1] Austria, Germany, Japan,[3] Pakistan,[4] Ukraine[5] and Indonesia.[6] Habitats which Dictyochloropsis has been cultured from include soil,[1][4][5] tree bark,[1][3][6] and hard surfaces such as rocks and concrete.[3]
Dictyochloropsis is also able to survive and grow in freshwater environments.[4] When isolated, Dictyochloropsis cultures are typically grown in nutrient-rich freshwater environments.[1][3][4]