Figure 4

Circular Dichroism Spectra of NA-CATH and NA-CATH:ATRA1-ATRA1. Pronounced dichroic minima at 222 and 208 nm are traits of helical peptides. While NA-CATH and NA-CATH:ATRA1-ATRA1 do not show significant helical character in 10 mM sodium phosphate, both peptides exhibit helical structure in 60 mM SDS in 10 mM phosphate buffer (pH 7) and in 50% TFE in 10 mM phosphate buffer (pH 7). Under both conditions, NA-CATH:ATRA1-ATRA1 displayed more pronounced helical character than NA-CATH. B. Helical Wheel projection. Helical wheel projections were made with http://kael.org/helical.htm (accessed on 12/15/10). The sequences of (a) NA-CATH and (b) NA-CATH:ATRA1-ATRA1 were projected onto the helical backbone. Altered residues are indicated by the arrows. Shaded residues indicate hypdrophobic residues. C. ATRA2 vs ATRA1 motifs in helical wheel projection. To enable easier viewing of contribution of the key differences between the ATRA2 (a) and the ATRA1 (b) motifs to the hydrophobic face of the peptide, each motif is projected alone on the helical wheel in this view. Altered residues are indicated by the arrows. Shaded residues indicate hypdrophobic residues.