TABLE 2.
AI-2 synthesis by Shigella species and EIEC
| Source of conditioned mediaa | Fold induction of luminescence in V. harveyi BB170b |
|---|---|
| 2457T (S. flexneri 2a) | 516 |
| BS607 (S. boydii) | 484 |
| 3818T (S. dysenteriae) | 521 |
| BS513 (S. sonnei) | 543 |
| ATM266 (EIEC) | 460 |
| BS620 (S. flexneri 2a ΔluxS∷aadA) | 1 |
| BB152c (V. harveyi, AI-2 positive) | 338 |
| MC4100c (E. coli K-12, AI-2 positive) | 427 |
| DH5αc (E. coli K-12, AI-2 negative) | 1 |
a
Conditioned media derived from cultures grown in LB–0.5% glucose at 37°C to an OD600 of 1.4 were prepared as described in Materials and Methods.
b
Fold induction represents the mean of three separate experiments measuring the luminescence of V. harveyi BB170 (sensor AI-1 negative, sensor AI-2 positive) cultured in conditioned media from the designated sources relative to that of V. harveyi BB170 grown in unconditioned LB.
c
AI-2 production by these strains has been previously characterized (33). Strains served as positive (BB152 and MC4100) and negative (DH5α) control sources of AI-2 sensed by BB170.