The species from this group can be distinguished from all other bacteria by the presence of conserved indels in a number of proteins such as RNA polymerase alpha subunit, Gyrase B, Elongation factor-T...The species from this group can be distinguished from all other bacteria by the presence of conserved indels in a number of proteins such as RNA polymerase alpha subunit, Gyrase B, Elongation factor-Tu and Elongation factor-P, and by large numbers of signature proteins that are uniquely present in different chlamydiae species.