Studies of the L-forms of Clostridium perfringens. I. Relationship of colony morphology and reversibility.

The L-forms of Clostridium perfringens were first reported by Dienes (1950). He described this form as minute, soft, pleomorphic colonies which developed when C. perfringens were grown on penicillin-treated horse serum agar plates. The reversion of L-colonies to bacterial forms has not been reported for C. perfringens. They have been observed in strains of Proteus (Dienes, 1949), Salmonellae (Weinberger et al., 1950), Hemophilus influenzae (Dienes and Weinberger, 1951), Bacteroides (Dienes, 1948), and Streptobacillus moniliformis (Dienes, 1943). The present study is the investigation of the transformation of known C. perfringens tvpes (A, B, C, D, E, and F), their respective L-forms, and an examination of the ability of the L-forms to revert to bacillary colonies.