The pSKAN Phagemid Display System for high-throughput screening of protein-protein interactions as well as for selection and production of novel proteins with specific binding properties and 3-D structure-based protein design. It can also be used for the development of affinity matrices, ligand and protease inhibitor screening, detection of allergens and the development of pharmaceuticals and diagnostics. pSKAN is a combinatorial phagemid library expressed in E. coli: the M13 phage coat protein pIII is fused to the hPSTI protein which contains a short stretch of 6-8 hypervariable amino acids. Analogous to antibodies this hyper-variable loop is monovalently exposed on the surface of the pSKAN phage for a very specific and selective binding to target molecules but — in contrast to antibodies — it is able to target very small, recessed epitopes of limited accessibility. The 3 pSKAN libraries MoBiTec offers are stable and have molecular diversity (approx. 3 × 10⁷ randomly recombined variants). They can be screened in a so-called "panning assay" for specific binding to a target molecule of interest. Variants with optimal affinity are selected and propagated in E. coli. Sequencing of the hyper-variable loop and the efficient production of the respective soluble recombinant hPSTI protein with the desired binding affinities is possible as well as construction of your own peptide library. The pSKAN system is easy to handle and a very useful, fast and low-cost alternative to antibodies and immunoglobulin domain-presenting phagemids since the scientist is able to isolate a target molecule of interest within only 3 weeks. Thus, animals and tissue cultures become superfluous. Specific anti-pIII and anti-hPSTI antibodies are available as well.