Fig. 4

Activities of TFPI-2 C-terminal derived peptides in human plasma. The bactericidal activity of TFPI-2 peptides was assessed in physiological buffer conditions using viable count analysis. a–e Bacteria E. coli ATCC 25922 were grown to mid-logarithmic phase and incubated with varying concentrations of peptides corresponding to sequences found in mammals, birds, reptiles, frog and fish species. Peptides were used in buffer containing 0.15 M NaCl, 10 mM Tris, pH 7.4 alone, or in presence of 20 % human plasma. The antimicrobial activity was determined by plating serial dilution of bacteria on TH agar plates and number of cfu was counted after overnight incubation. All investigated peptides showed dose dependent bactericidal activity and 100 % bacterial killing was achieved in all cases at 1 μM concentration