Fig 1.
The infected mice exhibited dose-dependent response to survival.
All the mice of four groups were injected intraperitoneally (i. p.) with a lethal dose, 2.2 × 107 CFU of E. coli and treated with different concentration of DAN2 after 30 minutes of bacterial challenge. The control group only received bacterial suspension and PBS. All the treated mice were monitored for five days. There were 6 mice/group.
Fig 2.
DAN2 treated mice have reduced bacterial loads both in peritoneal fluid and blood.
Four mice were infected and treated with 0 mg/kg, 20 mg/kg, 10 mg/kg and 5 mg/kg of DAN2 individually and bacterial count was determined after 6 hours of infections. The error bars represent the standard deviation of the mean. The number of asterisks was used to denote the extent of statistical significance amongst groups (* denotes p < 0.05, ** denotes p < 0.005, *** denotes p < 0.0005).
Fig 3.
DAN2 disrupts the integrity of E.coli cell membrane.
The DNA binding dye propidium iodide (PI) was used to evaluate cell membrane permeability of E. coli ATCC 25922 via flow cytometry. 2.0 × 106 CFU/ml was incubated with varying concentrations of peptide for an hour and PI added subsequently. Flow cytometry was performed using a FACScan instrument. (A) Bacteria; (B) Heat treated (positive control); (C) DAN2 (48 μg/ml); (D) DAN2 (36 μg/ml); (E) DAN2 (24 μg/ml). Bacterial cells treated with either peptide or heat shocked have increased cellular fluorescence intensity of PI.