A method for discovering one or more peptides adapted for specific binding to a microorganism of interest. The method comprises (i) identifying an antimicrobial peptide having antimicrobial activity against the microorganism of interest, (ii) generating a library of first generation mutants of the antimicrobial peptide, each of the first generation mutants differing from the antimicrobial peptide by a small number of amino acid substitutions, additions or deletions, (iii) screening the library of first generation mutants for those first generation mutants that bind to the microorganism of interest, (iv) determining the peptide sequences of those first generation mutants that bind to the microorganism of interest, and (v) if necessary, repeating steps (ii) through (iv) for one or more successive generations of mutants until one or more consensus peptide sequences emerge.