Protamine-induced permeabilization of cell envelopes of gram-positive and gram-negative bacteria

Charlotte Johansen, A. Verheul, Lone Gram, T. Gill, T. Abee

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The inhibitory effect of the cationic peptide protamine on Listeria monocytogenes, Escherichia coli, and Shewanella putrefaciens has been studied in detail, The addition of protamine (10 to 1,000 mu g/ml) resulted in inhibition of oxygen consumption after less than 1 min and loss of intracellular carboxyfluorescein and ATP after 2 to 5 min. Maximum antibacterial activity was reached at alkaline pH and in the absence of divalent cations. The efficient permeabilization of cell envelopes of both gram-positive and gram-negative bacteria suggests that protamine causes a general disruption of the cell envelope, leading to a rapid and nonspecific efflux of low- and high-molecular-weight compounds
Original languageEnglish
JournalApplied and Environmental Microbiology
Issue number3
Pages (from-to)1155-1159
Publication statusPublished - 1997

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