N storm a1 microscope

An exponentially growing P. aeruginosa PAO1-GFP culture in TSB medium at 37 °C was harvested by centrifugation, washed in sodium chloride solution, and resuspended to an OD₆₀₀ of 50 in sodium chloride solution. PAO1 without treatment was used as a control. XPa and PAO1 were stained with PI (50 ng/mL) for 5 min and observed on a 1.2% agarose pad using N-STORM&A1 microscope (Nikon) at 488 nm and 594 nm. XPa + DNase I samples were treated with DNase I (10 μg/mL) at 37 °C for 1 h, and then, the staining step was conducted. All samples were transferred to a thin agar pad on a microscope slide and imaged with the N-STORM&A1 microscope system (Nikon).

After exposure to X-ray irradiation at the dose of 0.98 kGy, the P. aeruginosa PAO1 suspensions were immediately stained with TOTO^TM-1 (2 μM) and FM^TM4-64 (5 μg/ml) for 5 min to label the nucleic acid and the membrane, respectively. A 2 μl droplet of cells were observed on a 1.2% agarose pad with N-STORM/A1 microscope (Nikon) at 488 nm and 561 nm. Image analysis was performed using NIS-ELEMENTS AR software (Nikon, Japan).