|
Planctobacteria is a taxon created by Cavalier-Smith, specifically a division (phylum).〔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.〕 However, it is not followed by the larger scientific community. Cavalier-Smith postulated that the Planctobacteria probably lost or reduced their peptidoglycan cell wall twice.〔 In the Cavalier-Smith bacterial megaclassification, it is within the bacterial Gracilicutes infrakingdom and comprises three classes Chlamydiae, Lentisphaerae, Planctomycetes, Verrucomicrobia. 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. }}}}}} ==Molecular evidence== Support for this superphylum has been found by examining the RNA polymerase protein RpoB. 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. 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.〔 The Planctomycetes may be basal to the Chlamydiae-Verrucomicrobia-Lentisphaerae clade. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Planctobacteria」の詳細全文を読む スポンサード リンク
|