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Time (h)
Figure 6. Growth curve for blank (doubling time: 77 min) and
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With all the compounds that showed inhibitory activi-
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in order to eliminate general toxicity reflected in re-
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reduced bioluminescence production. Briefly, bacteria
were grown for 16 h with aeration (175 rpm) at 30 °C
in 2 mL of AB medium with antibiotics (kanamycin
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In conclusion, several pyrogallol compounds were found
to exhibit AI-2 inhibition effect with IC50 values in the
single digit micromolar range. The potency observed
was much higher than the AI-2 antagonists reported in
the literatures. These pyrogallol analogs will be very use-
ful tools for research and good lead compounds for fur-
ther structural optimization.
Acknowledgments
23. Ribeiro, P. D.; Ribeiro, O. D.; Marcolan, A. M.; Medina-
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Financial support from the Molecular Basis of Disease
program at GSU, Georgia Research Alliance, and Geor-
gia Cancer Coalition is gratefully acknowledged.
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Supplementary data
Supplementary data associated with this article can be
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