Heterogeneity of Mycoplasma iowae determined by restriction enzyme analysis

Strains of Mycoplasma iowae were homogeneous in some characteristics and heterogeneous in others. Thus, the biochemical tests, immunofluorescence, and protein profiling by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were group-specific tests. However, some minor differences in protein patterns were seen among strains. The growth inhibition test tended to be strain-specific. Hemagglutination titers were very low and unstable for the majority of strains. One strain (RY-65) with a stable high-titer hemagglutinin failed to react in the hemagglutination-inhibition test against immune sera to the reference strains. Restriction endonuclease DNA analyses was the most useful method to differentiate 1 strain from another.