Susceptibility of Mycoplasma (Pleuropneumonia-like Organisms) and Bacterial Protoplasts to Lysis by Various Agents

Abstract

THE Mycoplasma organisms (pleuropneumonia-like organisms, PPLO) are limited by a thin and plastic cell envelope¹. The absence of diaminopimelic acid and hexosamines in Mycoplasma^2,3 indicates the absence of the ‘mucopeptide complex’ from their cell envelope. The thickness of the Mycoplasma cell envelope was found to be ∼ 75 Å.¹, which is similar to that of the cytoplasmic membrane of bacteria⁴. These findings might indicate that the Mycoplasma have no cell wall and are limited only by a membrane resembling the cytoplasmic membrane of bacterial protoplasts. In order to elucidate this point, a comparative study of some of the properties of the Mycoplasma organisms and bacterial protoplasts was carried out.