The Structure and Functions of the Mycoplasma Membrane

Abstract

Publisher Summary The plasma membrane is the site of a great number of essential functions in mycoplasmas, as it is with all organisms, but the membrane assumes an even greater importance with mycoplasmas because of their simplicity and lack of a cell wall. This chapter describes the structure and functions of the mycoplasma membrane. Many mycoplasmas are pathogenic, disease being caused in a number of animal, plant, and insect hosts. Mycoplasma membranes are of particular interest not only because of their involvement in disease because of adhesion to host cells, but also because they provide a system that is most suited to many investigations into the structure and function of biomembranes. Two principal reasons explain their suitability in biomembrane research. First, mycoplasmas grow in synthetic culture media and controlled alterations in membrane composition can be introduced by manipulation of the medium content. Second, mycoplasma membranes are easily prepared free from other cellular material. The composition of a membrane can be altered by its method of isolation. Mycoplasma membranes contain all the cell lipid and one-quarter to one-half of the cell protein. The gross chemical composition of the membranes varies with species but generally falls within the range of 50–60% protein, 30–40% lipid, and 1–3% carbohydrate.