What is "planctobacteria"

Planctobacteria is a taxon created by Cavalier-Smith, specifically a division ( phylum). 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. 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.