Rhizosolenia: Difference between revisions
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''Rhizosolenia'' is a unicellular rod shaped diatom and ranges in diameter size from 2.5-170 µm. The cell wall is made of a silica shell comprised of two separate valves, also known as a frustule. The cell can synthesize the biogenic silica needed for the construction of the frustules. In addition the total silica production contributes a siginificant amount in the global marine silica cycle. ''Rhizosolenia'' is mostly abundant in a mat formation containing communities of multiple ''Rhizosolenia'' species. The mats can be comprised of short chains of only a few cells or larger rigid chains ranging from 1-30cm wide. | ''Rhizosolenia'' is a unicellular rod shaped diatom and ranges in diameter size from 2.5-170 µm. The cell wall is made of a silica shell comprised of two separate valves, also known as a frustule. The cell can synthesize the biogenic silica needed for the construction of the frustules. In addition the total silica production contributes a siginificant amount in the global marine silica cycle. ''Rhizosolenia'' is mostly abundant in a mat formation containing communities of multiple ''Rhizosolenia'' species. The mats can be comprised of short chains of only a few cells or larger rigid chains ranging from 1-30cm wide. | ||
The size of the large mat communities can be a disadvantage in survival when competing with nano and pico sized organisms in an oligotrophic aquatic environment. To overcome this disadvantage, ''Rhizosolenia'' mats photosynthesize at the surface and then undergo a vertical migration (>300m) to exploit nutrients. | |||
With the increase of carbohydrates in the cell from photosynthesis the cell becomes negatively buoyant and has a downward migration. As the carbohydrates are consumed and there is an uptake of nitrate a positively buoyant upward vertical migration takes place. This migration can take 3.4-5.4 days. | |||
Nitrate uptake from ''Rhizosolenia'' mats is stored in internal pools. The nitrogen maybe utilized by the mats, released into surrounding waters as a way to dissipate excess energy or relieve stress, or to be remineralized by macro and microzooplankton. The ''Rhizosolenia'' play an important role in the nitrogen cycle at the photic zone with the release of nitrogen. | |||
==Ecology and Pathogenesis== | ==Ecology and Pathogenesis== | ||
Revision as of 21:15, 20 April 2008
Classification
Eukaryota; Ochrophyta; Coscinodiscophyceae; Rhizosoleniales; Rhizosoleniacease [Others may be used. Use NCBI link to find]
Species
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NCBI: Taxonomy |
Rhizosolenia acicularis; R. acuminata; R. acuminate; R. alata forma gracillima; R. alata forma curvirostris; R. alata forma gracillima; R. alata forma indica; R. alata gracillima; R. alata inermis; R. antarctica; R. antennata; R. antennata forma semispina; R. arafurensis; R. barboi; R. bergonii; R. bezrukovae; R. borealis; R. braunii; R. bulbosa; R. calcar-avis; R. castracanei; R. castracanei var. neglecta; R. chunii; R. clevei; R. clevei var. communis; R. cochlea; R. costata; R. crassa; R. crassispina; R. cretacea; R. curvata; R. curvirostria; R. curvirostris; R. debyana; R. decipiens; R. drafurensis; R. eriensis var. gracilis; R. eriensis var. morosa; R. eriensis var. morsa; R. faeroensis ; R. fallax; R. firma; R. formosa; R. fragillissima; R. gracilis; R. gravida; R. hebetata; R. hebetata forma semispina; R. hyalina; R. imbricata; R. interposita; R. longiseta; R. massiva; R. minima; R. miocenica; R. morsa; R. norwegica; R. ostenfeldii; R. palliola; R. pokrovskajae; R. polydactyla; R. polydactyla forma squamosa; R. praealata; R. praebarboi; R. pungens; R. rhombus; R. robusta; R. setigera; R. sigma; R. sima; R. sima forma silcea; R. similis; R. similoides; R. simplex; R. stolterforthii; R. striata; R. styliformis; R. temperei; R. truncata; R. twistata
Description and Significance
Describe the appearance, habitat, etc. of the organism, and why you think it is important.
Genome Structure
There has not been a genome project on Rhizosolenia spp. at this time.
Cell Structure, Metabolism and Life Cycle
Rhizosolenia is a unicellular rod shaped diatom and ranges in diameter size from 2.5-170 µm. The cell wall is made of a silica shell comprised of two separate valves, also known as a frustule. The cell can synthesize the biogenic silica needed for the construction of the frustules. In addition the total silica production contributes a siginificant amount in the global marine silica cycle. Rhizosolenia is mostly abundant in a mat formation containing communities of multiple Rhizosolenia species. The mats can be comprised of short chains of only a few cells or larger rigid chains ranging from 1-30cm wide.
The size of the large mat communities can be a disadvantage in survival when competing with nano and pico sized organisms in an oligotrophic aquatic environment. To overcome this disadvantage, Rhizosolenia mats photosynthesize at the surface and then undergo a vertical migration (>300m) to exploit nutrients.
With the increase of carbohydrates in the cell from photosynthesis the cell becomes negatively buoyant and has a downward migration. As the carbohydrates are consumed and there is an uptake of nitrate a positively buoyant upward vertical migration takes place. This migration can take 3.4-5.4 days.
Nitrate uptake from Rhizosolenia mats is stored in internal pools. The nitrogen maybe utilized by the mats, released into surrounding waters as a way to dissipate excess energy or relieve stress, or to be remineralized by macro and microzooplankton. The Rhizosolenia play an important role in the nitrogen cycle at the photic zone with the release of nitrogen.
Ecology and Pathogenesis
Habitat; symbiosis; biogeochemical significance; contributions to environment.
If relevant, how does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
References
Author
Page authored by Erin Hagen and Amanda Herzog, student of Prof. Jay Lennon at Michigan State University.
