Fig 5.

Sensitivity of P. gingivalis W83, FLL32, FLL455, and FLL456 to UV irradiation. Dilutions of fresh cultures of the P. gingivalis strains were grown anaerobically to exponential phase in BHI broth from overnight cultures and spread on BHI agar. The cells were irradiated with the indicated UV radiation. Plates were incubated at 37°C for 7 to 10 days, and CFU were counted. Each experiment was done in triplicate. The error bars show standard deviations. *, P ≤ 0.05; **, P ≤ 0.01; asterisks without brackets represent comparison to the value for untreated samples.