Abstract
The general characteristics of these strains were those of mycoplasmas; these included cultural and metabolic characters, morphological appearance in stained films and electron micrographs, growth inhibition by specific antiserum and a DNA base composition of 28·5 per cent. GC. However, the group showed some unusual features, including failure to pass readily through membrane filters of 450 nm pore diameter, poor growth in conventional mycoplasma media and production of atypical colonies on GS agar medium.
The serological identity of strains classified as M. dispar was demonstrated by growth and metabolic inhibition tests. They were serologically distinct from other recognised bovine mycoplasmas and from a wide range of mycoplasmas from other sources.