(A) Amino acid sequence of CHIF (NCBI accession: NP_068702). Residue numbering begins at 1 after the signal sequence. Leu in H1 and H2 are in red. Leu22 and Leu35 were introduced by mutations of native Met. (B) Secondary structure, 1H-15N RDCs, and 1H/15N heteronuclear NOEs (gray bars), for CHIF in micelles. Positions left blank correspond to Pro (3, 9, 49, 53, 58, 62) or overlapped peaks. Sample preparation and NMR experiments were as described5, 7.