Candidatus Carsonella ruddii
Candidatus Carsonella ruddii | |
---|---|
Scientific classification | |
Kingdom: | |
Phylum: | |
Class: | |
Order: |
unclassified
|
Genus: |
Candidatus Carsonella
|
Species: |
Ca. C. ruddii
|
Binomial name | |
Candidatus Carsonella ruddii Thao et al. 2000
|
Lua error in Module:Taxonbar/candidate at line 22: attempt to index field 'wikibase' (a nil value).
Candidatus Carsonella ruddii is an obligate endosymbiotic Gamma Proteobacterium[1] with one of the smallest genomes of any characterised bacteria.[2]
Endosymbiosis
The species is an endosymbiont that is present in all species of phloem sap-feeding insects known as psyllids.[3][4] The endosymbionts occurs in a specialised structure known as the bacteriome.
Genome
In 2006 the genome of Ca. C. ruddii strain Pv (Carsonella-Pv) of the hackberry petiole gall psyllid, Pachypsylla venusta, was sequenced at RIKEN in Japan and the University of Arizona. It was shown that the genome consists of a circular chromosome of 159,662 base pairs and that it has a high coding density (97%) with many overlapping genes and reduced gene length. The number of predicted genes was 182, also the lowest on record (NCBI-Genome). In comparison, Mycoplasma genitalium, which has the smallest genome of any free-living organism, has a genome of 521 genes. Numerous genes considered essential for life seem to be missing, suggesting that the species may have achieved organelle-like status.[2]
At the time of its sequencing, C. ruddii was thought to have the smallest genome of any characterized bacterial species.[5] Nasuia deltocephalinicola is now considered to have the known smallest bacterial genome (112kb).[6]
C. ruddii and related species appear to be actively undergoing gene loss.[7]
References
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
External links
- Scientific American – Tiny Genome May Reflect Organelle in the Making