Persister-promoting bacterial toxin TisB produces anion-selective pores in planar lipid bilayers. FEBS letters 586(16), 2529-2534

Program in Physical Biology, National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
FEBS letters (Impact Factor: 3.17). 06/2012; 586(16):2529-34. DOI: 10.1016/j.febslet.2012.06.021
Source: PubMed


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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Available from: Philip A Gurnev, Mar 28, 2014
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    • "In contrast, most of the toxins of the type I and type V TA systems, such as TisB and GhoT, target the inner membrane (26,47,99–101) (Table 2). They inhibit ATP synthesis by depleting the proton motive force, leading to dramatic RNA decay, thus halting protein synthesis (47). "
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