Transforming Protein Engineering Infrastructure: Using PicoShells for Rapid Directed Evolution of Complex Functions

This project aims to transform the field of protein engineering by developing an innovative technology called PicoShells. PicoShells are tiny, hollow particles that can hold and test large numbers of proteins quickly and efficiently. With PicoShells, scientists can screen up to one million different protein variations in just one day to find useful proteins for research, industrial or medical applications. This rate of screening improves substantially over current methods, which makes it easier to look through many new proteins to identify ones with useful functions. This project is important because it helps solve key problems in protein research, such as finding the proteins best suited to particular functions, such as sensing glucose concentration in the body and reporting it, which can help diabetic patients avoid low or high glucose levels in the blood that cause health problems. By making this process of protein identification faster and more effective, PicoShells can lead to new discoveries in medicine, energy, and environmental science. Additionally, this project supports education by involving students in research and creating teaching materials for schools to learn about concepts like concentration, polymers, and phase separation. Overall, the development of PicoShells will benefit society by speeding up scientific advancements and helping train the next generation of scientists. This research focuses on advancing protein engineering through the development of PicoShells, which are hollow, porous microparticles made of functionalized polyethylene glycol (PEG). PicoShells can encapsulate various cell types, including bacteria, yeast, microalgae, and mammalian cells, while keeping them viable or allowing for protein retention and testing for activity and properties after cell lysis. The project has two main objectives: first, to develop methods for retaining antibodies and enzymes within PicoShells to expand their use beyond their current application as fluorescent protein sensors; second, to create a comprehensive workflow for the directed evolution of proteins, specifically targeting high-performing variants of a fluorescent calcium biosensor and glucose biosensor. PicoShells can enable the rapid screening of proteins under multiple environmental conditions and analyte concentrations using fluorescence-activated cell sorting (FACS), significantly enhancing the scale and efficiency of directed evolution and protein engineering. The project's outcomes will provide the research community with a transformative tool for protein design and development, accelerating discoveries and innovations in biological research and creating data sets important for developing machine learning models to design proteins with specific functions. Results of the project will be available at www.biomicrofluidics.com. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.