Production of L Forms of Neisseria meningitidis by Antibiotics

Abstract

Summary

L forms of group B Neisseria meningitidis were produced by penicillin, methicillin, ampicillin, cephalothin, cyclo-serine, ristocetin, bacitracin and vancomycin. These L forms were propagated serially on medium containing each antibiotic, and all L forms had similar growth, morphologic and fermentative properties. Revertant organisms from each antibiotic-induced L form had the same fermentative properties and antibiotic sensitivities as the respective parent meningococcus. Furthermore each revertant strain agglutinated with group B meningo-coccal antisera. L forms were more resistant than the parent organism to those antibiotics that were capable of producing L forms, except in the case of ristocetin where parent and L forms exhibited the same sensitivity. Parent and L form organisms exhibited similar sensitivities to novo-biocin, tetracycline and erythromycin, and L forms were not produced by these antibiotics or by sulfisoxazole.