Detailed description of FRET, NMR and MD results.

Binding parameters for transmembrane TM2 and TM3 segments in SDS micelle by FRET experiments (Table A). Hydrodynamic parameters by DOSY spectroscopy (Table B). 15N relaxation rates for 15N-labeled alanines in TM2, TM3 peptides and TM2:TM3 pairs extracted from NMR data (Table C). CD spectra (Fig A). Distance between Pro85 and Pro231 in TM2 and TM3 fragments of BTL protein (Fig B). 1H-15N HSQC spectra (Fig C). FT PGSE analysis of DPFGDSTE experiment for SDS micelle, TM2, TM3, and TM2:TM3 mixture. (Fig D). Spatial structure of studied species from NMR data. (Fig E). Experimental R1 and R2 relaxation rates for 15N-labeled alanines in TM2 fragment (Fig F). Experimental R1 and R2 relaxation rates for 15N-labeled alanines (Ala225 and Ala233) in TM3 (Fig G). Experimental R1 and R2 relaxation rates for 15N-labeled alanines (Ala225' and Ala233') in minor conformation of the TM3 (Fig H). Experimental values of 15N R1, R2 relaxation rates and {1H}-15N NOE (Fig I). Results of analysis of 15N relaxation data for TM2 and TM3 fragments (Fig J).
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