Peptides

Abstract

A cyclic polyarginine peptide comprising at least one motif: X1-X2-X3-RRR-X4-X5-X6 wherein X1 and X6 are amino acid residues other than arginine and X1 is stapled to X6; X2, X3, X4 and X5 are, independently, either absent or amino acid residues other than arginine and the arginine content of the peptide is at least 40% w / w. The peptide may comprise the motif CRRRC wherein the cysteines are stapled via a bidentate moiety, a disulfide bridge or a tridentate, tetradentate, pentadentate or hexadentate stapling moiety. The cyclic peptide may further comprise between 3 and 50 arginine residues and may have a spacer at the N-terminus or C-terminus, the spacer selected from S, G, GS, A, Ahx, Ado, PEG, Sar or gamma-E. The cyclic peptide may have the sequence RCRRRCRRCRRRCR. The peptide may be labelled and may be an inhibitor of acid-sensing ion channels (ASICs, e.g. ASIC1a). [No Figure]