sequences (see Figure). The phylum for Mollicutes The results of Mollicutes phylogenetic analyses have been controversial. Some taxonomists place them in Bacillota, others in Mycoplasmatota. Woese et al. suggested that the Mollicutes might have been derived from different branches of bacteria. They concluded, that the Mollicutes are not a phylogenetically coherent group and therefore do not form a distinct higher level taxon. Instead, they cluster within Gram-positive bacteria of the phylum Bacillota. The results of molecular phylogenetic analyses have been partly dependent on the chosen molecular marker, like rRNA, elongation factor or another protein. Phylogenetic trees based on phosphoglycerate kinase (Pgk) amino acid sequences' indicated a monophyletic origin for the Mollicutes within the Bacillota. An early edition of Bergey's Manual of Systematic Bacteriology placed class Mollicutes within phylum Bacillota, whereas in the announced 2nd edition, they are moved to a separate phylum Tenericutes (later renamed Mycoplasmatota). The change is motivated by "their unique phenotypic properties, in particular the lack of rigid cell walls, and the general low support by alternative markers". In the Taxonomic Outline of Bacteria and Archaea (TOBA Release 7.7), March 2007, the Mollicutes are a class in the phylum Bacillota. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI) ♦ Paraphyletic Mollicutes See also List of bacterial orders List of bacteria genera References External links Bacteria classes