Fig. 5

Transmission electron micrographs of E. coli. a (i) and (ii), untreated control of whole (×40 K zoom) and single cell (×100 K zoom) bacterial suspension, respectively, showing typical E. coli shapes; a (iii) and (iv), E. coli’s whole (×40 k zoom) and single cell (×100 K zoom) suspension, respectively, treated with 5× MIC (40 µg/mL) of YD1, showing irregular shapes. b Percentage of E. coli spheroplasts and whole cells remaining intact during exposure to YD1. Assays were performed in tris buffer with 20% w/v sucrose at OD 570 nm. c Plasmid DNA binding affinity measured for increasing amounts of YD1 (concentration ranging from 8–80 µg/mL). d Effects of YD1 on cell viability. Cell viability was measured after 24 h incubation. Survival rates were tested with MTT assay in Raw 264.7 cells. Raw 264.7 cells were incubated in the presence or absence of 8–120 µg/mL YD1 for 24 h. Each bar shows the mean ± S.D of three independent experiments performed in triplicate