Measurement of bacterial protein leakage by SDS-PAGE.

(A), The SDS-PAGE gel image indicated the extracellular bacterial proteins (leaked into the medium, lane 1–3) and intracellular bacterial proteins (lane 4–6) before (control, lane 1, 4) and after C200-photocatalysis (visible light) for 1 minute (lane 2, 5) and 5 minutes (lane 3, 6), respectively. One representative image out of three experiments is shown. Total protein in the cells after the treatments was used as an internal control for quantification (lane 4–6). The numbers on the left indicate the molecular weights of the marker proteins in units of kDa. (B) The quantitative results of SDS-PAGE. The quantification was based on intensity measurements on the whole lanes using Image J software. The average protein levels in lanes 1–3 were first divided by the average protein levels in lanes 4–6, respectively, and then the ratio (lane 1/lane 4) of untreated groups was normalized to 100%. *** P<0.001, compared to the untreated control group.