TABLE 1.
MICs for plantaricin peptidesa
Indicator strain | Peptide MIC (nM) of:
|
|||
---|---|---|---|---|
PlnJK | PlnEF | PlnA 22-mer | PlnA 26-mer | |
Pediococcus pentosaceus Pac 1.0 | 50 | 5 | 100 | 100 |
Lactobacillus plantarum 965 | 0.1 | 7 | 500 | 300 |
Lactobacillus casei subsp. casei NCDO 161 | ≥400 | 20 | 250 | 250 |
Lactobacillus casei NCDO 2713 | ≥400 | 150 | ≥6,000 | ≥6,000 |
Lactobacillus sake NCDO 2714 | 50 | 4 | 250 | 60 |
Lactobacillus viridescens NCDO 1655 | 5 | 2 | 50 | 20 |
Pediococcus pentosaceus NCDO 990 | ≥400 | 30 | ≥6,000 | ≥6,000 |
Carnobacterium piscicola UI49 | ≥400 | ≥400 | ≥6,000 | ≥6,000 |
Lactobacillus plantarum UI50 | ≥400 | ≥400 | ≥6,000 | ≥6,000 |
Lactobacillus sake 706 | ≥400 | 100 | ≥1,000 | ≥500 |
Pediococcus acidilactici CH | ≥400 | 10 | NTb | ≥500 |
Lactobacillus curvatus 89 | ≥400 | 5 | NT | ≥500 |
Bacteriocin activity was determined as described previously (22). The values are the concentrations of peptides that caused 50% growth inhibition of the indicator strains. The peptides making up PlnJK and PlnEF were mixed at a 1:1 ratio. PlnN was tested against all indicator strains, but no antagonistic activity was detected at any concentration (the highest concentration tested was approximately 1 μM). The PlnA 23-mer peptide was tested against L. plantarum 965 and exhibited antagonistic activity similar to that of the PlnA 22-mer peptide.
NT, not tested.