Typing of isolates of Mycoplasma pneumoniae and Mycoplasma salivarium by growth inhibitors derived from mycoplasmal cells treated with chloroform.

Isolates of Mycoplasma pneumoniae and M. salivarium could be subclassified at the strain level by inhibitors (ch-Mcin) derived from mycoplasmal cells treated with chloroform. Sixty-one isolates of M. pneumoniae obtained from oral cavities of patients were divided into three types by their ch-Mcin: a definite type which completely inhibits the growth of M. fermentans PG18, an indefinite type and a noinhibition type. Sixty-seven isolates of M. salivarium were also divided into similar types by their ch-Mcin which does or does not inhibit the growth of M. salivarium Hup127. In the case of isolates of M. pneumoniae and M. salivarium belonging to the indefinite type which gave ambiguous patterns in the ch-Mcin typing, it was demonstrated that they could be clearly typed by further testing after repeated cloning.