(538b) Modular Protein Self-Assembly: Building Bio-Inspired Materials with Genetically Programable Functionality

Proteins are the essential biological building blocks in living systems to build sophisticated biological assemblies with highly controllable properties and functions. Significant effort has been devoted to mimicking the processes of protein self-assembly toward advanced materials, but it often fails to replicate the complexity and efficiency of native systems. We have found that by using protein zippers we can create modular systems to genetically program functions into self-assembled protein biomaterials. Specifically, coiled coils, the α-helical protein motifs that oligomerize with high affinity and specificity have been widely used as versatile toolkits to create functional protein assemblies. The sequence-to-structure relationships of coiled coils have been understood well, leading to the de novo design of coiled-coil sequences with controllable specificity, oligomeric state, length, and helix orientation. Exploiting the coiled-coil interactions through genetic fusion of recombinant proteins, we have demonstrated modular protein self-assembly to create functional protein biomaterials. Using this approach, we have designed fluorescent protein nanoclusters to image multiplexed signaling network dynamics in cells. Additionally, we have engineered biocompatible fluorescent coating materials that quantify calcium ions in biological systems to detect abnormal physiological conditions such as mild or moderate hypercalcemia. Finally, by combining a natural coat protein with a coiled-coil protein motif, we have developed a modularly programmable platform to build antifouling and antimicrobial surfaces. Through these technologies, we have consistently demonstrated that the genetic combination of coiled-coil toolkits and functional protein domains enables highly modular functional biomaterials engineering that could be extended to a variety of applications.