Antigenicity of Mycoplasma Membranes

Abstract

UNLIKE bacteria, mycoplasmas do not have a rigid cell wall^1,2, but they are bounded by a triple layered limiting mombrane 70–80 Å thick³. Immunological reactions with these organisms have been studied by a number of techniques, of which growth inhibition and haemagglutination inhibition are believed to represent reactions with the surface of the organism^4,5. Whole mycoplasma cells of different species have been chemically fractionated by various workers^4,6–10 and found to contain carbohydrates, proteins and lipids. Studies, particularly on Mycoplasma pneumoniae, have shown that most of the antigenic activity is associated with lipids which react with antibody, and when combined with protein stimulate antibody, including growth-inhibiting antibody⁴. It is tempting to believe that these lipids have been extracted from the cell membrane because lipids are an integral part of membranes of many cells. Physical methods have been described for the preparation of isolated membranes from mycoplasmas¹¹ and we have isolated membranes from the serologically distinct organisms M. gallisepticum (S6) and M. pneumoniae (FH) and have attempted to stimulate, in particular, growth-inhibiting antibody with them.