Antimicrobial peptides in action

Antimicrobial peptides (AMPs) exhibit a wide range of antimicrobial and antifungal activity and have attracted significant interest as potential antibiotics. However, the mechanism of action of antimicrobial peptides is still poorly understood and, from experimental data, different membrane disruption structural models have been proposed. We study the mechanisms of AMPs by simulating their action at different levels of detail: from atomistic [1, 2] to coarse grained molecular dynamics (MD) simulations [3]

From our MD simulations, we have been able to propose a new mechanism for membrane poration by linear antimicrobial peptides: the disordered toroidal pore [1, 2]. The ability of cationic AMPs to cluster negatively charged lipids has also been addressed [4]. Furthermore, we were able to provide detailed insight on the mechanism of pore-forming cyclic peptides in an effort that brought together simulation results and in vitro measurements of peptide activity [5].

[1] H. Leontiadou, A.E. Mark, S.J. Marrink. Antimicrobial peptides in action. J. Am. Chem. Soc. 128:12156-12161, 2006.

[2] D. Sengupta, , H. Leontiadou, A.E. Mark, S.J. Marrink. Toroidal pores formed by antimicrobial peptides show significant disorder. Biochim. Biophys. Acta. 1778:2308-ì2317, 2008.

[3] A. J. Rzepiela, D. Sengupta, N. Goga, S.J. Marrink. Membrane poration by antimicrobial peptides combining atomistic and coarse-grained descriptions. Faraday Discuss., 144:431-443, 2010.

[4] A.A. Polyansky, R. Ramaswamy, P.E. Volynsky, I.F. Sbalzarini, S.J. Marrink, R.G. Efremov. Antimicrobial p eptides i nduce g rowth of p hosphatidylglycerol d omains in a m odel b acterial m embrane. J. Phys. Chem. Lett., 1: 3108-3111, 2010

[5] A.D. Cirac, G. Moiset, J.T. Mika, A. Kocer, P. Salvador, B. Poolman, S. J. Marrink,  D. Sengupta. The molecular basis for antimicrobial activity of pore-forming cyclic peptides. Biophys. J. 100:2422-31, 2011.

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