A peptide having the amino acid sequence of formula (I) H2N-X1-R-X3-X2-COOH wherein X1 is either zero or X1 and/or X2 are a residue representing at least five amino acid residues (symbolized in the one letter amino acid code), preferably naturally occurring amino acids, with the proviso that X1 and/or X2 contain at least one basic amino acid residue immediately followed by a hydrophobic amino acid residue and X1 and/or X2 contain at least one glutamine residue.
