The instant invention refers to an antibacterial peptide with all amino acids in D-configuration, possessing strong antimicrobial activity against Gram-negative and Gram-positive bacteria and Candida strains. The peptide can be in linear form multimerised on a skeleton of polyacrylamide, of dextrane units or on a skeleton of ethylene glycol units. The peptide is resistant proteolysis especially when synthesized in the tetra-branched form where identical peptide sequences are linked together by an appropriate molecular scaffold.