Fig. 1.
Effect of AgNPs on L. monocytogenes growth (A) and survival (B).
Solid lines – control; dashed lines – 0.25 MIC AgNPs; dotted lines – 0.5 MIC AgNPs. Mean ± SD values of triplicate cultures were shown.
Fig. 2.
Influence of AgNPs on lysozyme- or Triton X-100-induced autolysis/lysis of L. monocytogenes.
White bar – control, buffer only; dark grey bar – lysozyme or Triton X-100; light grey bar – lysozyme or Triton X-100 + 0.25 MIC AgNPs; black bar – lysozyme or Triton X-100 + 0.5 MIC AgNPs. The results are mean of three independent experiments with every measurement done in triplicate ± SD. Statistically relevant differences (p < 0.05) were marked with asterisks.
Fig. 3.
Autolysis of isolated L. monocytogenes peptidoglycan in the presence of AgNPs.
Absorbance A600 at time 0 was considered as 100%. Solid line – control; dashed line – 0.25 MIC AgNPs; dotted line – 0.5 MIC AgNPs. The results are mean of three independent experiments with every measurement done in triplicate ± SD. Statistically relevant difference (p < 0.05) was marked with an asterisk.
Table I
Increase in cF efflux from L. monocytogenes caused by AgNPs.
| AgNPs concentration | % efflux of cF at time (min) | |
|---|---|---|
| 0 | 10 | |
| 0 (negative control) | 72 ± 2 | 79 ± 1 |
| 0.25 MIC | 73 ± 2 | 84 ± 2 |
| 0.5 MIC | 74 ± 2 | 93* ± 2 |
Fig. 4.
Effect of AgNPs influence on the efflux of DNA and proteins from L. monocytogenes.
White bars – control, no AgNPs added; dark grey bars – 0.25 MIC AgNPs; light grey bars – 0.5 MIC AgNPs; black bars – 100 μg/ml lysozyme (positive control). The results are mean of three independent experiments with every measurement done in triplicate ± SD. Statistically relevant difference (p < 0.05) were marked with asterisks.