TABLE 2.

Hemolytic activity ratios and LD50s of L. monocytogenes LLO strains

StrainaHemolytic activity ratio (dilution at pH 5.5/dilution at pH 7.4)bLD50c
Wild type9.54.2 × 104
K25R9.74.8 × 104
K25G11.35.3 × 104
K25V10.54.7 × 104
K25L11.1UD
K25F11.93.5 × 104
K25A11.33.7 × 104
K25T11.5UD
  • a Mutant strains are identified by the mutations in their LLOs.

  • b Ratio of the dilutions of supernatants from L. monocytogenes strains grown in LB broth to late stationary phase required for 50% lysis of sheep red blood cells when assayed at pH 5.5 and 7.4.

  • c The LD50s were determined by injecting 6-week-old female BALB/c mice with twofold dilutions via the tail vein and monitoring the mice for 7 days. UD, undetermined.