We studied membrane activity of the bacterial peptide TisB involved in persister cell formation. TisB and its analogs form multi-state ion-conductive pores in planar lipid bilayers with all states displaying similar anionic selectivity. TisB analogs differing by ±1 elementary charges show corresponding changes in selectivity. Probing TisB pores with poly-(ethylene glycol)s reveals only restricted partitioning even for the smallest polymers, suggesting that the pores are characterized by a relatively small diameter. These findings allow us to suggest that TisB forms clusters of narrow pores that are essential for its mechanism of action.
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| http://dx.doi.org/10.1016/j.febslet.2012.06.021 | DOI Listing |
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