TABLE 2.
Hemolytic activity ratios and LD50s of L. monocytogenes LLO strains
| Straina | Hemolytic activity ratio (dilution at pH 5.5/dilution at pH 7.4)b | LD50c |
|---|---|---|
| Wild type | 9.5 | 4.2 × 104 |
| K25R | 9.7 | 4.8 × 104 |
| K25G | 11.3 | 5.3 × 104 |
| K25V | 10.5 | 4.7 × 104 |
| K25L | 11.1 | UD |
| K25F | 11.9 | 3.5 × 104 |
| K25A | 11.3 | 3.7 × 104 |
| K25T | 11.5 | UD |
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.