FIG 3.

ROS scavenger DMTU mitigates the inhibitory effect of blue light. EGD-e cells were illuminated with blue light (460 to 470 nm, 1.5 to 2 mW cm⁻²) either on BHI agar (A) or in liquid culture (B) with or without 20 mM DMTU. (A) Overnight cultures were standardized to an OD₆₀₀ of 1.0 and diluted to 10⁻⁸. Four microliters of each dilution was spotted in triplicate onto BHI agar (−) or BHI agar supplemented with 20 mM DMTU (+) and grown at 30°C for 24 h. (B) Final OD measurements (left) and difference in lag time (right). Starting cells were equalized to an OD₆₀₀ of 0.05 and diluted to 10⁻⁶. Cultures were grown in 96-well plates at 30°C for 24 h in BHI broth with or without 20 mM DMTU. The values represent the means of the results from three individual replicates. The error bars represent the standard deviations between samples. Student's t test was carried out to determine the statistical difference between cultures grown with and without DMTU. (B) Asterisks indicate significant differences (P ≤ 0.05).