Voltage activated ion channels formed by a synthetic alpha-helical peptide: - Determination of channel stoichiometry and molecular modelling of peptide conformation

• Autorzy: Mellor I. R. , Kerr I.D. , Sansom M.S.P. , Sukumar M. , Balaram P.
• Języki publikacji: EN

Abstrakty

EN

We designed and synthesized an 18 residue peptide (MS 18) similar to the channel forming fungal antibiotic alamethicin. MS18 formed ion channels in lipid bilayers exhibiting a low discrete conductance level of 55 pS and brief openings to many other conductance levels. Channel formation was markedly dependent on transbilayer voltage with macroscopic conductance increasing exponentially beyond an activation voltage. The activation voltage was higher for lower concentrations of peptide. The relationship between conductance, voltage and peptide concentration was used to calculate the mean number of peptide monomers forming the MS18 channel. This gave an estimate of 4 MS18 monomers per channel. Molecular modeling of MS18 revealed a predominantly α-helical structure.

Słowa kluczowe

EN

peptide conformation; conductance; stoichiometry; alpha-helical peptide; channel; alpha-helical structure; activation voltage; molecular modelling; peptide concentration; lipid bilayer; antibiotic; alamethicin; ion channel

• Wydawca: -
• Czasopismo: Cellular and Molecular Biology Letters
• Rocznik: 1996
• Tom: 01
• Numer: 3
• Opis fizyczny: p.325-336,fig.

Twórcy

autor

Mellor I. R.

• University of Nottingham, University Park, Nottingham, NG7 2RD, U.K.

autor

Kerr I.D.

autor

Sansom M.S.P.

autor

Sukumar M.

autor

Balaram P.

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