DEINOCOCCUS–THERMUS is a phylum of bacteria that are highly
resistant to environmental hazards, also known as extremophiles .
These bacteria have thick cell walls that give them gram-positive
stains, but they include a second membrane and so are closer in
structure to those of gram-negative bacteria.
this clade HADOBACTERIA (from
* 1 Taxonomy * 2 Molecular Signatures * 3 Phylogeny * 4 Taxonomy * 5 Sequenced genomes * 6 References
The phylum _Deinococcus-Thermus_ consists of a single class (_ Deinococci _) and two orders:
* The _ Deinococcales _ include two families (_ Deinococcaceae _ and_Trueperaceae _), with three genera, _ Deinococcus _, _ Deinobacterium _ and _ Truepera _. _ Truepera radiovictrix _ is the earliest diverging member of the order. Within the order, _ Deinococcus _ forms a distinct monophyletic cluster with respect to _ Deinobacterium _ and _ Truepera species _. The genus includes several species that are resistant to radiation; they have become famous for their ability to eat nuclear waste and other toxic materials, survive in the vacuum of space and survive extremes of heat and cold. * The _ Thermales _ include several genera resistant to heat (_Marinithermus _, _ Meiothermus _, _Oceanithermus _, _ Thermus _, _Vulcanithermus _, _Rhabdothermus _) placed within a single family, _Thermaceae _. Phylogenetic analyses demonstrate that within the_ Thermales _, _ Meiothermus _ and _ Thermus _ species form a monophyletic cluster, with respect to _Marinithermus _, _Oceanithermus _, _Vulcanithermus _ and _Rhabdothermus _ that branch as outgroups within the order. This suggests that _ Meiothermus _ and _ Thermus _ species are more closely related to one another relative to other genera within the order._ Thermus aquaticus _ was important in the development of the polymerase chain reaction where repeated cycles of heating DNA to near boiling make it advantageous to use a thermo-stable DNA polymerase enzyme.
Though these two groups evolved from a common ancestor, the two mechanisms of resistance appear to be largely independent.
Molecular Signatures in the form of conserved signature indels (CSIs) and proteins (CSPs) have been found that are uniquely shared by all members belonging to the _Deinococcus-Thermus_ phylum. These CSIs and CSPs are distinguishing characteristics that delineate the unique phylum from all other bacterial organisms, and their exclusive distribution is parallel with the observed differences in physiology. CSIs and CSPs have also been found that support order and family-level taxonomic rankings within the phylum. Some of the CSIs found to support order level distinctions are thought to play a role in the respective extremophilic characteristics. The CSIs found in DNA-directed RNA polymerase subunit beta and DNA topoisomerase I in _ Thermales _ species may be involved in thermophilicity , while those found in Excinuclease ABC, DNA gyrase , and DNA repair protein RadA in _ Deinococcales _ species may be associated with radioresistance . Two CSPs that were found uniquely for all members belonging to the Deinococcus genus are well characterized and are thought to play a role in their characteristic radioresistant phenotype. These CSPs include the DNA damage repair protein PprA the single-stranded DNA-binding protein DdrB.
Additionally, some genera within this group, including _Deinococcus _, _ Thermus _ and _ Meiothermus _, also have molecular signatures that demarcate them as individual genera, inclusive of their respective species, providing a means to distinguish them from the rest of the group and all other bacteria. CSIs have also been found specific for _ Truepera radiovictrix _ .
The phylogeny is based on 16S rRNA-based LTP release 123 by \'The All-Species Living Tree\' Project .
_Rhabdothermus arcticus _ Steinsbu et al. 2011
_Vulcanithermus mediatlanticus _ Miroshnichenko et al. 2003
_O. desulfurans _ Mori et al. 2004
_O. profundus _ Miroshnichenko et al. 2003 (type sp.)
_Marinithermus hydrothermalis _ Sako et al. 2003
_ Meiothermus _
_ Thermus _
_ Truepera radiovictrix _ Albuquerque et al. 2005
_ Deinobacterium chartae _ Ekman et al. 2011
_ Deinococcus _
Note: ♠ Strains found at the National Center for Biotechnology Information (NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature (LSPN)
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
* Class DEINOCOCCI Garrity Hadobacteria Cavalier-Smith 2002; "Xenobacteria"]
* Order DEINOCOCCALES Rainey et al. 1997
* Family Deinococcaceae Brooks and Murray 1981 emend. Rainey et al. 1997
* Family Trueperaceae Rainey et al. 2005
* Genus _ Truepera _ da Costa, Rainey and Albuquerque 2005
* Order THERMALES Rainey and Da Costa 2002
* Family Thermaceae Da Costa and Rainey 2002
* Genus _ Thermus _ Brock and Freeze 1969 emend. Nobre et al. 1996 * Genus _ Meiothermus _ Nobre et al. 1996 emend. Albuquerque et al. 2009 * Genus _Marinithermus _ Sako et al. 2003 * Genus _Oceanithermus _ Miroshnichenko et al. 2003 emend. Mori et al. 2004 * Genus _Rhabdothermus _ Steinsbu et al. 2011 * Genus _Vulcanithermus _ Miroshnichenko et al. 2003
Currently there are 10 sequenced genomes of strains in this phylum.
* _ Deinococcus radiodurans_ R1 * _ Thermus thermophilus_ HB27 * _ Thermus thermophilus_ HB8 * _ Deinococcus geothermalis_ DSM 11300 * _ Deinococcus deserti_ VCD115 * _ Meiothermus ruber_ DSM 1279 * _ Meiothermus silvanus_ DSM 9946 * _ Truepera radiovictrix_ DSM 17093 * _Oceanithermus profundus_ DSM 14977
The two _Meiothermus_ species were sequenced under the auspices of
the Genomic Encyclopedia of
* ^ _A_ _B_ Griffiths E, Gupta RS (September 2007). "Identification
of signature proteins that are distinctive of the
Thermus phylum" (PDF). _Int. Microbiol_. 10 (3):
201–8. PMID 18076002 . Archived from the original (PDF) on
* ^ Gupta RS (2011). "Origin of diderm (Gram-negative) bacteria:
antibiotic selection pressure rather than endosymbiosis likely led to
the evolution of bacterial cells with two membranes" . _Antonie Van
Leeuwenhoek_. 100 (2): 171–182. PMC 3133647 _. PMID 21717204 .
doi :10.1007/s10482-011-9616-8 .
* ^ Campbell C, Sutcliffe IC, Gupta RS (2014). "Comparative
proteome analysis of Acidaminococcus intestini supports a relationship
between outer membrane biogenesis in
Proteobacteria". Arch Microbiol_. 196 (4): 307–310. PMID 24535491 .
doi :10.1007/s00203-014-0964-4 .
* ^ Sutcliffe IC (2010). "A phylum level perspective on bacterial
cell envelope architecture". _Trends Microbiol_. 18 (10): 464–470.
PMID 20637628 . doi :10.1016/j.tim.2010.06.005 .
Cavalier-Smith T (2006). "Rooting the tree of life by
transition analyses". _Biol. Direct_. 1: 19. PMC 1586193 _. PMID
16834776 . doi :10.1186/1745-6150-1-19 .
* ^ A_ _B_ Albuquerque L, Simões C, Nobre MF, et al. (2005).
Truepera radiovictrix gen. nov., sp. nov., a new radiation resistant
species and the proposal of Trueperaceae fam. nov.". _FEMS Microbiol
Lett_. 247 (2): 161–169. PMID 15927420 . doi
* ^ _A_ _B_ Garrity GM, Holt JG. (2001)
* v * t * e
* Acidophile * Alkaliphile * Capnophile * Cryozoa * Endolith * Halophile * Hypolith * Lipophile * Lithoautotroph * Lithophile * Methanogen * Metallotolerant * Oligotroph * Osmophile * Piezophile * Polyextremophile * Psammophile * Psychrophile * Radioresistant * Thermophile / Hyperthermophile * Thermoacidophile * Xerophile
Abiogenic petroleum origin
Acidophiles in acid mine drainage
* v * t * e
G- / OM
Terra-/ Glidobacteria (BV1 )
* Deinococcus- Thermus
* _thermophiles _
Proteobacteria (BV2 )
* Acidithiobacillales * Aeromonadales * Alteromonadales * Cardiobacteriales * Chromatiales * Enterobacteriales * Legionellales * Methylococcales * Oceanospirillales * Orbales * Pasteurellales * Pseudomonadales * Salinisphaerales * Thiotrichales * Vibrionales * Xanthomonadales
Sphingobacteria ( FCB group )
* Chlorobiales * Ignavibacteriales
* Lentisphaerales * Oligosphaerales * Victivallales
* Phycisphaerales * Planctomycetales
* Puniceicoccales * Opitutales * Chthoniobacterales * Verrucomicrobiales
* " Poribacteria "
* Acidobacteriales * Acanthopleuribacterales * Holophagales * Solibacterales
* Armatimonadales * Chthonomonadales * Fimbriimonadales
G+ / no OM