TABLE 3.

Biological activity of peptides against Gram-negative bacteria after 24 h at 37°C

	Minimal inhibitory concentration (μg/ml)*
Peptide	P. aeruginosa K799 (H187)	P. aeruginosa† Z61(H188)	E. coli UB1005	E. coli† DC2	S. typhimurium C587	S. typhimurium† C610	Geometric mean Gram-negative‡
GS	25	6.2	9.0	3.1	18	9.0	5.6
GS10YY	50	6.2	25	6.2	200	25	9.9
GS10WW	100	12.5	50	6.2	200	200	24.9

A minimum of three experiments was performed for each biological activity assay. For the definition of geometric mean, please see footnote^§ in Table 2.

^*Activity against Gram-negative bacteria was measured in liquid broth assays as described previously ((14) and references therein).

^†Supersusceptible derivatives of Gram-negative bacteria with more permeable outer membranes.

^‡Mean MIC values (after 24 h) against supersusceptible Gram-negative bacteria, P. aeruginosa Z61, E. coli DC2, and S. typhimurium C610.