Studies on the effect of growth medium composition on the antigenicity of Mycoplasma bovis

Serum proteins adsorbed from the culture medium were detected in Mycoplasma bovis antigens, the number and type of proteins depending on the serum used in the medium. The alpha-globulins cross-reacted with alpha-globulins from different types of sera but the gamma-globulins did not. The removal of non-specific medium antibodies by absorption showed that they affected the gel diffusion and growth precipitation tests, producing cross-reactions between M. bovis and M. bovigenitalium, but that the complement fixation, tube agglutination, and growth inhibition tests were not similarly affected. The presence of serum proteins in the antigens changed their specific reactivity in all the tests. The production of antibodies to serum proteins was increased by the use of an adjuvant, but it appeared that production of specific antibodies to the mycoplasmas was not.

Studies on the adsorption of certain medium proteins to Mycoplasma gallisepticum and their influence on agglutination and haemagglutination reactions

Serum proteins from Mycoplasma gallisepticum culture medium could be detected on the organisms as a result of incubation at low pH. Only certain of the serum proteins, including IgG and IgM, were found, and the adsorption appears to depress the haemagglutinating activity of the organisms. There was no obvious effect on slide agglutination (SA) sensitivity but an incidental finding was that brief acid treatment enhanced the SA sensitivity of an antigen prepared from a young culture.

Nuclease activities of Mycoplasma gallisepticum as a function of culture age in different media

Levels of deoxyribonuclease and ribonuclease activities in the supernatant (soluble plus ribosomes) fraction of Mycoplasma gallisepticum were assayed and found to be a function of strain, nutrient, and culture age. In yeast hydrolysate-enriched broth, maximal nuclease activities occurred during exponential growth.

Investigation into rabbit infusion media for the growth of Mycoplasma gallisepticum antigens for inoculation into rabbits

Serum cholesterol in rabbits was elevated, by intravenous inoculation of 20% Tween 80, to amounts thought to have been sufficient to support growth of Mycoplasma gallisepticum when 20% of such serum was added to rabbit infusion broth.However, better growth of the organism was obtained with a supplement of 5% rabbit serum and commercial cholesterol. Investigation showed that normal rabbit serum may be inhibitory, which would explain these findings. The commercial cholesterol was not antigenic.