THE IN VITRO SENSITIVITY OF VARIOUS MYCOPLASMA STRAINS TO ANTIMICROBIAL AND ANTITUMOR AGENTS

Abstract

The antimycoplasmal activity of 40 antimicrobial and 14 antitumor agents to 13 Mycoplasma species were tested by method of the agar dilution and the microtiter assays. The following results were obtained.
1. All of the macrolide so far tested such as leucomycin, spiramycin, josamycin and tylosin, except for erythromycin and oleandomycin, showed high antimycoplasmal effect without no difference among Mycoplasma species. Lincomycin also inhibited the growth of Mycoplasma at lower concentration.
2. Tetracycline, oxytetracycline and demethylchlortetracycline were found to have high antimycoplasmal activity.
3. In the antitumor antibiotycs, bleomycin did not show antimycoplasma activity, but the others such as actinomycin D, mitomycin C, daunomycin and chromomycin A₃ showed strong activity against all strains of Mycoplasma tested.
4. On the other hand, 9 antitumor agents were generally insensitive.
5. Aminoglucoside antibiotics such as streptomycin, kanamycin, neomycin and paromomycin showed the middle sensitivity but the activity in this group differed according to Mycoplasma strains.
6. Chloramphenicol was sensitive at range from 6. 25 to 1. 25 μg/ml.
7. In naphthyridine derivatives, nalidixic acid was insensitive, but in piromidic acid there were differences in minimal inhibitory concentration against the tested strains.
8. The excellent susceptibility was observed in 5 nitrofurans derivatives without exception.
9. Penicillin-cephalosporin groups, polypeptides such as bacitracin, colistin and polymyxin-B, and all of 6 sulfa drugs were insensitive.
10. As compared with agar dilution method, the microtiter technique was superior in minimal concentration.