Figure 4.

Effect of LPS E. coli K-235 on antimicrobial activity of LL37, melittin (Mel), alamethicin (Ala), gramicidin A (GrA), gramicidin S (GrS), and polymyxin B (Poly). (A) E. coli (B) S. aureus. Ratios (w/w 1:1 and w/w 1:5) are in parentheses. Bacteria were incubated with the peptides at their MBC in 10 mM sodium phosphate buffer (pH 7.4) containing LPS for 2 h at 37 °C and suitably diluted aliquots were plated on LB agar plates, which were incubated at 37 °C for 18 h. Colonies formed were counted and percentage bacteria killed was determined.