10.1021/ja072851d.s001 Alexander D. Milov Alexander D. Milov Rimma I. Samoilova Rimma I. Samoilova Yuri D. Tsvetkov Yuri D. Tsvetkov Fernando Formaggio Fernando Formaggio Claudio Toniolo Claudio Toniolo Jan Raap Jan Raap Self-Aggregation of Spin-Labeled Alamethicin in ePC Vesicles Studied by Pulsed Electron−Electron Double Resonance American Chemical Society 2007 position 16 resonance technique 0.2. 3.5 acid concentration 2.3 nm label width Electron function model peptide ePC Vesicles Studied 77 K electron interaction 1.3 nm ePC vesicles tetramethylpiperidine form aggregates Pulsed ResonanceThe 4.2 Alamethicin alamethicin molecules data alamethicin analogue 2007-08-01 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Self_Aggregation_of_Spin_Labeled_Alamethicin_in_ePC_Vesicles_Studied_by_Pulsed_Electron_Electron_Double_Resonance/2993779 The pulsed electron−electron double resonance technique was used to study the dipole−dipole interactions between 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid spin labels located at position 16 of an alamethicin analogue in ePC vesicles that were frozen to 77 K. We show that under these conditions the alamethicin molecules tend to form aggregates over the range of peptide concentrations 3.5 × 10<sup>-3</sup> to 1 × 10<sup>-2</sup> M. The number of molecules in the aggregate is found to be 4.2 ± 0.2. A spin-label distance distribution function is also obtained with a maximum at a distance of 2.3 nm and a half-height width of 1.3 nm. We envisage that these data will permit us to generate a molecular model of cellular ion channels