Bradykinin

    Modifications of the terminal parts of the peptide type ligands resulted significant increases and decreases in activity (e.g. bradykinin derivatives) Kőhidai et al. (2002),

Chemotactic effect of bradykinin (RPPGFSPFR) and derivatives. Truncation of the ligand results loss in chemoattractant moiety, however expression of Phe on the N-terminus overridges the chemotactic ability of the native (BK1-9) ligand.

                                                                                                                            Lecture ►

    Endothelin

    The increased number of aromatic amino acid residues in the interacting regions of the molecules were responsible for significant loss in chemotactic ability (e.g endothelins) (Kőhidai et al. 2001).

 

Chemotaxis induced with endothelins. Black line represents ET-1 - the only wide range chemoattractant endothelin derivative. Presence of aromatic amino acids in the loop-region of the molecule (ET-2 and ET-3) results chemorepellent ligands, while the linear fragment (ETfr11-21) still possess sligh chemoattractant moiety.

 

Structure of endothelins. Circles filled green represent amino acids with aromatic sidechains.