Chloroflexus aurantiacus: Difference between revisions
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''C. aurantiacus'' is often classified with green non-sulfur bacteria. As described above, this organism is an anoxygenic phototroph, which utilizes bacteriochlorophylls a & c. Furthermore, ''C. aurantiacus'' utilizes these bacteriochlorophylls as the primary directors of their light-harvesting processes. This organism primarily utilizes organic material as a possibly energy source, consuming the organic byproducts of cyanobacteria that it commonly associates with. However, it may also utilize hydrogen or sulfide as an electron donor when found on its own. This implies that ''C. aurantiacus'' can be a photolithotroph and a photoheterotroph. | ''C. aurantiacus'' is often classified with green non-sulfur bacteria. As described above, this organism is an anoxygenic phototroph, which utilizes bacteriochlorophylls a & c. Furthermore, ''C. aurantiacus'' utilizes these bacteriochlorophylls as the primary directors of their light-harvesting processes. This organism primarily utilizes organic material as a possibly energy source, consuming the organic byproducts of cyanobacteria that it commonly associates with. However, it may also utilize hydrogen or sulfide as an electron donor when found on its own. This implies that ''C. aurantiacus'' can be a photolithotroph and a photoheterotroph. | ||
The reductive pentose phosphate pathway (Calvin cycle) and 3-hydroxy-propionate pathway are both used to fix carbon within this organism. Oddly, ''C. aurantiacus'' lacks the ribulose bisphosphate carboxylase protein. This enzyme is normally involved in glyceraldehyde-3-phosphate production in the Calvin cycle. So far, ''C. aurantiacus is the only anoxygenic phototrophic bacteria to demonstrate the 3-hydroxy-propionate pathway. This pathway ultimately produces pyruvate from the glyoxylate cycle to produce carbon skeletons for further metabolism. Variants of this pathway are relatively uncommon, however it is speculated that a similar pathway is carried out within Crenarchaeota. | The reductive pentose phosphate pathway (Calvin cycle) and 3-hydroxy-propionate pathway are both used to fix carbon within this organism. Oddly, ''C. aurantiacus'' lacks the ribulose bisphosphate carboxylase protein. This enzyme is normally involved in glyceraldehyde-3-phosphate production in the Calvin cycle. So far, ''C. aurantiacus'' is the only anoxygenic phototrophic bacteria to demonstrate the 3-hydroxy-propionate pathway. This pathway ultimately produces pyruvate from the glyoxylate cycle to produce carbon skeletons for further metabolism. Variants of this pathway are relatively uncommon, however it is speculated that a similar pathway is carried out within Crenarchaeota. | ||
==Ecology== | ==Ecology== | ||
Revision as of 21:47, 24 April 2010
Classification
Bacteria (Domain); Chloroflexi (Phylum); Chloroflexi (Class); Chloroflexales (Order); Chloroflexaceae (Family) [Others may be used. Use NCBI link to find]
Species
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NCBI: Taxonomy |
Chloroflexus aurantiacus
Description and Significance
C. aurantiacus is described as anoxygenic, thermophilic, filamentous, gliding, phototrophic bacteria commonly found in hot springs under normal to alkaline pH conditions. C. aurantiacus is a gram-negative organism. The optimal temperature range for the growth for this organism is approximately 50-60°C. It is commonly known to exist in areas with high sulfide concentrations and adequate periods of direct sunlight. C. aurantiacus can be found in microbial mats with other strains of photosynthetic bacteria or found in isolation. C. aurantiacus is commonly utilized as a model organism and is found to be critical to scientific research into the evolution of photosynthetic organisms.
Genome Structure
The genome for C. aurantiacus has been completely sequenced by the U.S. Department of Energy's Joint Genome Institute. Its genetic code consists of 5,258,241 base pairs of DNA concentrated within a single circular chromosome. 3,990 genes have been sequenced within this organism's genome, but of these, 219 possess a function unknown to scientists at this time. 80% of the genome of C. aurantiacus is known to code for functional proteins relevant to the sustainability of the cell. No portion of the genome is utilized for RNA modification. 61 structural RNAs are also encoded within the genome of C. aurantiacus.
Cell Structure
The cellular structure of this organism primarily contains a thin layer of peptidoglycan. This peptidoglycan is a variant that mainly utilizes L-ornithine as a diamino acid. Lipopolysaccharides are entirely absent from the outer membrane. However, studies cannot conclude whether or not this organism entirely lacks an outer membrane.
The cytoplasmic membrane is a crucial aspect of the overall cellular structure of C. aurantiacus. Several chlorosomes are attached to the inner wall of the cytoplasmic membrane. These serve to aid C. aurantiacus with its' photosynthetic processes, acting as light-harvesting units. These chlorosomes are also noted for containing bacteriochlorophyll c; a photosynthetic pigment that is only known to occur within Chloroflexi.
Metabolism
C. aurantiacus is often classified with green non-sulfur bacteria. As described above, this organism is an anoxygenic phototroph, which utilizes bacteriochlorophylls a & c. Furthermore, C. aurantiacus utilizes these bacteriochlorophylls as the primary directors of their light-harvesting processes. This organism primarily utilizes organic material as a possibly energy source, consuming the organic byproducts of cyanobacteria that it commonly associates with. However, it may also utilize hydrogen or sulfide as an electron donor when found on its own. This implies that C. aurantiacus can be a photolithotroph and a photoheterotroph.
The reductive pentose phosphate pathway (Calvin cycle) and 3-hydroxy-propionate pathway are both used to fix carbon within this organism. Oddly, C. aurantiacus lacks the ribulose bisphosphate carboxylase protein. This enzyme is normally involved in glyceraldehyde-3-phosphate production in the Calvin cycle. So far, C. aurantiacus is the only anoxygenic phototrophic bacteria to demonstrate the 3-hydroxy-propionate pathway. This pathway ultimately produces pyruvate from the glyoxylate cycle to produce carbon skeletons for further metabolism. Variants of this pathway are relatively uncommon, however it is speculated that a similar pathway is carried out within Crenarchaeota.
Ecology
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 Eric Mrozek & Bob Moore, students of Prof. Jay Lennon at Michigan State University.
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