(427c) Elastin-Calmodulin Scaffold for Protein Microarray Fabrication

Protein microarray have become an important tool for advancing disease diagnostics and proteomics analysis due to their ability in providing high throughput screening. Since screening occurred in a dedicated region on an array surface, the ability to spatially pattern protein in a simple and general manner is essential. In this work, we report a new method to reversibly immobilize proteins to a surface in a functionally active orientation directly from cell lysate by employing a fusion protein consists of a thermal-responsive elastin domain as the surface anchor and a calcium-responsive calmodulin domain for protein capturing. Incorporation of a M13 tag into recombinant proteins enables not only easy surface immobilization but also direct purification from cell lysates. The feasibility of concept was demonstrated using the M13-tagged yellow fluorescent protein (M13TYFP). The proper orientation of calmodulin domain was achieved by selective adhesion of elastin domain onto a hydrophobic surface. The resulting functionalized surfaces were shown to capture M13TYFP directly from cell lysate through the specific calmodulin-M13 association in a calcium dependent manner. We also demonstrated that immobilization is reversible; the bound proteins were released from the surface in the presence of calcium chelators.