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The structure of a melittin-stabilized pore.

ABSTRACT: Melittin has been reported to form toroidal pores under certain conditions, but the atomic-resolution structure of these pores is unknown. A 9-?s all-atom molecular-dynamics simulation starting from a closely packed transmembrane melittin tetramer in DMPC shows formation of a toroidal pore after 1 ?s. The pore remains stable with a roughly constant radius for the rest of the simulation. Surprisingly, one or two melittin monomers frequently transition between transmembrane and surface states. All four peptides are largely helical. A simulation in a DMPC/DMPG membrane did not lead to a stable pore, consistent with the experimentally observed lower activity of melittin on anionic membranes. The picture that emerges from this work is rather close to the classical toroidal pore, but more dynamic with respect to the configuration of the peptides.

SUBMITTER: Leveritt JM

PROVIDER: S-EPMC4457010 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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The structure of a melittin-stabilized pore.

Leveritt John M JM Pino-Angeles Almudena A Lazaridis Themis T

Biophysical journal 20150501 10

Melittin has been reported to form toroidal pores under certain conditions, but the atomic-resolution structure of these pores is unknown. A 9-μs all-atom molecular-dynamics simulation starting from a closely packed transmembrane melittin tetramer in DMPC shows formation of a toroidal pore after 1 μs. The pore remains stable with a roughly constant radius for the rest of the simulation. Surprisingly, one or two melittin monomers frequently transition between transmembrane and surface states. All ...[more]

PMID: 25992720

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Project description:This SuperSeries is composed of the SubSeries listed below.

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