Planctobacteria

PVC group
Chlamydia trachomatis
Scientific classification (temporary)
Domain: Bacteria
Superphylum: PVC group
Phyla

Chlamydiae
Lentisphaerae
Planctomycetes
Verrucomicrobia

Synonyms

Planctobacteria Cavalier-Smith, 1987[1]

Planctobacteria is a taxon created by Cavalier-Smith, specifically a division (phylum).[note 1] However, it is not followed by the larger scientific community.[2] Cavalier-Smith postulated that the Planctobacteria probably lost or reduced their peptidoglycan cell wall twice.[3]

In the Cavalier-Smith bacterial megaclassification, it is within the bacterial Gracilicutes infrakingdom and comprises three classes Chlamydiae, Lentisphaerae, Planctomycetes, Verrucomicrobia.[3][4] These three groups in the traditional molecular phylogeny view are considered as phyla and also cluster together in what is referred to as the PVC superphylum, along with the candidate phyla OP3 and the Poribacteria.[5] It has been hypothesised that a member of the PVC clade might have been the host cell in the endosymbiotic event that gave rise to the first proto-eukaryotic cell.[6][7]

PVC superphylum[8][9][10]

Poribacteria


Planctomycetes

OP3

Chlamydiae

Lentisphaerae

Verrucomicrobia





Molecular evidence

Support for this superphylum has been found by examining the RNA polymerase protein RpoB.[11] This protein has a unique 3 amino acid insert in all sequenced Chlamydiae, Lentisphaerae and Verrucomicrobia species. A conserved protein of unknown function is present in all sequenced species from the phyla Chlamydiae, Lentisphaerae, Planctomycetes and Verrucomicrobia. This protein is absent in the Poribacteria.

Additional lines of evidence for the existence of this clade have been found.[12][13] These include the presence of membrane coat like proteins, tubulin, sterol synthesis and the presence of condensed DNA.

Study of additional proteins from this proposed syperphylum suggests that the Poribacteria may be separate from this clade.[11] The Planctomycetes may be basal to the Chlamydiae-Verrucomicrobia-Lentisphaerae clade.

Notes

  1. ↑ Historically bacteria were considered plants consequently the usage of "division" over "phylum" was brought over when the kingdom Monera was established. The bacteriological code has since imposed that the rank should be phylum and not division. Nevertheless, Cavalier-Smith adopts the term division.

References

  1. ↑ Cavalier-Smith, T. (1987). The origin of eukaryote and archaebacterial cells. Annals of the New York Academy of Sciences 503, 17–54.
  2. ↑ Krieg, N.R.; Ludwig, W.; Whitman, W.B.; Hedlund, B.P.; Paster, B.J.; Staley, J.T.; Ward, N.; Brown, D.; Parte, A. (November 24, 2010) [1984(Williams & Wilkins)]. George M. Garrity, ed. The Bacteroidetes, Spirochaetes, Tenericutes (Mollicutes), Acidobacteria, Fibrobacteres, Fusobacteria, Dictyoglomi, Gemmatimonadetes, Lentisphaerae, Verrucomicrobia, Chlamydiae, and Planctomycetes. Bergey's Manual of Systematic Bacteriology 4 (2nd ed.). New York: Springer. p. 908. ISBN 978-0-387-95042-6. British Library no. GBA561951.
  3. 1 2 Cavalier-Smith, T (2002). "The neomuran origin of archaebacteria, the negibacterial root of the universal tree and bacterial megaclassification". International Journal of Systematic and Evolutionary Microbiology 52 (Pt 1): 7–76. doi:10.1099/00207713-52-1-7. PMID 11837318.
  4. ↑ Cavalier-Smith T (2006). "Rooting the tree of life by transition analyses". Biol. Direct 1 (1): 19. doi:10.1186/1745-6150-1-19. PMC 1586193. PMID 16834776.
  5. ↑ Wagner, M.; Horn, M. (2006). "The Planctomycetes, Verrucomicrobia, Chlamydiae and sister phyla comprise a superphylum with biotechnological and medical relevance". Current Opinion in Biotechnology 17 (3): 241–249. doi:10.1016/j.copbio.2006.05.005. PMID 16704931.
  6. ↑ Forterre, Patrick (January 2011). "A new fusion hypothesis for the origin of Eukarya: better than previous ones, but probably also wrong". Research in Microbiology 162 (1): 77–91. doi:10.1016/j.resmic.2010.10.005.
  7. ↑ Baum, David A; Baum, Buzz (28 October 2014). "An inside-out origin for the eukaryotic cell". BMC Biology 12 (1). doi:10.1186/s12915-014-0076-2.
  8. ↑ Rappe, M. S.; Giovannoni, S. J. (2003). "The Uncultured Microbial Majority". Annual Review of Microbiology 57: 369–394. doi:10.1146/annurev.micro.57.030502.090759. PMID 14527284.
  9. ↑ Woese, C. R. (1987). "Bacterial evolution". Microbiological reviews 51 (2): 221–271. PMC 373105. PMID 2439888.
  10. ↑ Wagner, M.; Horn, M. (2006). "The Planctomycetes, Verrucomicrobia, Chlamydiae and sister phyla comprise a superphylum with biotechnological and medical relevance". Current Opinion in Biotechnology 17 (3): 241–249. doi:10.1016/j.copbio.2006.05.005. PMID 16704931.
  11. 1 2 Gupta RS, Bhandari V, Naushad HS (2012). "Molecular Signatures for the PVC Clade (Planctomycetes, Verrucomicrobia, Chlamydiae, and Lentisphaerae) of Bacteria Provide Insights into Their Evolutionary Relationships". Front Microbiol 3: 327. doi:10.3389/fmicb.2012.00327. PMC 3444138. PMID 23060863.
  12. ↑ Wagner M, Horn M (2006). "The Planctomycetes, Verrucomicrobia, Chlamydiae and sister phyla comprise a superphylum with biotechnological and medical relevance". Curr. Opin. Biotechnol. 17 (3): 241–9. doi:10.1016/j.copbio.2006.05.005. PMID 16704931.
  13. ↑ Kamneva OK, Liberles DA, Ward NL (2010). "Genome-wide influence of indel Substitutions on evolution of bacteria of the PVC superphylum, revealed using a novel computational method". Genome Biol Evol 2: 870–86. doi:10.1093/gbe/evq071. PMC 3000692. PMID 21048002.


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