Mycoplasmas are microorganisms that are previously popular as Pleuropneumonia -like organisms, of PPLO. Mycoplasmas was first recognized by Louis Pasteur as the etiological agent of bovine pleuropneumonia, although he did not observe it microscopically. In 1898, No card and Roux succeeded in growing the agent in cell-free medium, and in 1910 its morphology was described by other scientists.