How to Denominate “Four Pathogens and One Bacterium”

Abstract:

Mycoplasma, Chlamydia, Rickettsia, Spirochetes and Actinobacteria were generally called “four pathogens and one bacterium”. It was always difficult to be denominated and classified rightly in textbooks, while it was also a key interfering with students to grasp the concept of bacteria exactly. So we raise the question and hope to learn from each other by an exchange of views here.