FIG. 6.

Comparative cytotoxicities of supernatants from C. perfringens mutants. The cytotoxicities of supernatants from the strains indicated below were determined using the B16 melanoma cell line as described in Materials and Methods. The averages and standard deviations for at least three independent experiments are indicated. (A) Symbols: •, wild type; ▴, nanI mutant carrying the nanI⁺ complementation plasmid; ○, nanI mutant; ▵, nanI mutant carrying the vector plasmid. (B) Symbols: •, wild type; ▴, nanJ mutant carrying the nanJ⁺ complementation plasmid; ○, nanJ mutant; ▵, nanJ mutant carrying the vector plasmid. (C) Symbols: •, wild type; ▴, nanIJ mutant carrying the nanIJ⁺ complementation plasmid; ○, nanIJ mutant; ▵, nanIJ mutant carrying the vector plasmid. Twofold dilutions from 1/2 to 1/16 are indicated on the x axes.