Article

Persister-promoting bacterial toxin TisB produces anion-selective pores in planar lipid bilayers

Program in Physical Biology, National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
FEBS letters (Impact Factor: 3.34). 06/2012; 586(16):2529-34. DOI: 10.1016/j.febslet.2012.06.021
Source: PubMed

ABSTRACT 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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