GROWTH OF L FORMS OF STREPTOMYCIN-DEPENDENT PROTEUS MIRABILIS.

Altenbern, Robert A. (U.S. Army Biological Laboratories, Fort Detrick, Frederick, Md.). Growth of L forms of streptomycin-dependent Proteus mirabilis. J. Bacteriol. 85:619-622. 1963.-A streptomycin-dependent mutant of Proteus mirabilis produces L forms on penicillin-containing medium when dihydrostreptomycin is also present. The 3A-type L form grows at maximal rate when the concentration of dihydrostreptomycin is between 10 and 50 mug/ml, whereas the 3B-type L form grows appreciably only at concentrations of dihydrostreptomycin of 500 mug/ml or more. These results strongly suggest that propagation of 3A-type L forms does not proceed through intermediate formation of a 3B-type L body. The low quantitative dihydrostreptomycin requirement for growth of the 3A-type L forms indicates an abnormal membrane as compared with the 3B-type L forms or the normal cells of this streptomycin-dependent mutant.