TABLE 3.

Relative MICs of the pediocin PA-1 variants

Position	Indicator strain	Mean corresponding relative MIC ± SD for mutation ofa:
		Leu	Asp	Arg	Ala	Gly
K20	E. faecalis	4.2 ± 0.9	33 ± 10	0.8 ± 0.5	1.6 ± 0.7	ND
	L. coryniformis	5.7 ± 1.6	24 ± 6	0.7 ± 0.3	2.0 ± 0.4
	L. sakei	3.7 ± 0.9	21 ± 2	0.9 ± 0.4	1.1 ± 0.4
	C. piscicola	2.3 ± 0.6	17 ± 10	0.8 ± 0.4	1.1 ± 0.5
A21	E. faecalis	21 ± 8	≥500	≥150	WT	5.1 ± 1.2
	L. coryniformis	3.5 ± 1.1	≥250	≥120		2.6 ± 1.0
	L. sakei	3.5 ± 0.2	≥500	≥100		6.5 ± 0.4
	C. piscicola	17 ± 3	≥150	80 ± 15		3.3 ± 1.4
T23	E. faecalis	5.9 ± 1.3	2.1 ± 0.9	1.0 ± 0.6	1.9 ± 0.7	ND
	L. coryniformis	3.4 ± 0.7	4.5 ± 2.6	0.5 ± 0.4	1.8 ± 0.9
	L. sakei	2.7 ± 0.1	4.5 ± 0.4	1.8 ± 0.7	3.7 ± 1.5
	C. piscicola	4.2 ± 1.0	2.5 ± 0.6	0.8 ± 0.6	1.8 ± 1.1
N27	E. faecalis	15 ± 6	20 ± 8	1.7 ± 0.6	1.4 ± 0.6	ND
	L. coryniformis	5.8 ± 1.4	25 ± 11	0.6 ± 0.2	0.8 ± 0.4
	L. sakei	5.4 ± 1.6	12 ± 1	2.9 ± 0.8	2.2 ± 0.7
	C. piscicola	15 ± 2	12 ± 7	3.0 ± 1.7	1.5 ± 1.2
A34	E. faecalis	ND	30 ± 8	≥130	WT	1.5 ± 0.6
	L. coryniformis		10 ± 2	≥1,000		1.0 ± 0.3
	L. sakei		26 ± 8	30 ± 15		1.5 ± 0.7
	C. piscicola		15 ± 2	≥100		1.3 ± 0.3

^aThe relative MICs are the MICs of the mutant peptides divided by the MICs of wild-type pediocin PA-1. Each relative MIC is the result of at least 3 independent measurements. The MICs of wild-type pediocin PA-1 were between 0.1 and 0.5 nM (depending on the indicator cell). The L. coryniformis and L. sakei strains were 2 to 5 times more sensitive to pediocin PA-1 than the E. faecalis and C. piscicola strains. ND indicates not determined. Replacement with a Gly residue was done only when replacement with an Ala residue was not relevant due to the presence of an Ala residue in pediocin PA-1. The A34L mutation was not analyzed because we were unable to produce this variant, despite several attempts. WT indicates wild-type bacteriocin, and the relative MIC is thus 1.