Figure 1. Amphipathic helix model of the E^rns membrane anchor.

2D flat projection of the 3D structure of the E^rns anchor (Lys167 – Ala227) assuming a continuous α-helical conformation. Positively charged amino acids are shown in dark blue (Arg, Lys), negatively charged ones in red (Asp, Glu), and hydrophobic amino acids are colored in yellow (Leu, Val, Ile, Met, Trp, Tyr, Phe, Ala, Cys). Polar amino acids are displayed in light blue (Thr, Asn, Ser, Gln, His), and the remaining ones (Gly, Pro) in green. The illustration was generated with the in-house software “Protein Origami” (Karlsruhe Institute of Technology, http://www.ibg.kit.edu/nmr/544.php).