The invention relates to surface display of proteins on micro-organisms via the targeting and anchoring of heterologous proteins to the outer surface of cells such as yeast, fungi, mammalian and plant cells, and bacteria. The invention provides a proteinaceous substance comprising a reactive group and at least one attaching peptide which comprises a stretch of amino acids having a sequence corresponding to at least a part of the consensus amino acid sequence listed in FIG. 10 and comprises a method for attaching a proteinaceous substance to the cell wall of a micro-organism comprising the use of said attaching peptide.