CAREER: Leveraging Protein Engineering for Geotechnical Applications: Protein-Enhanced Biocementation for Soil Stabilization

This Faculty Early Career Development Program (CAREER) award supports research to develop a new approach for strengthening soil by using engineered proteins to precisely control how and where mineral binders form between soil particles. Conventional soil stabilization methods often rely on large quantities of cementitious materials to compensate for the unpredictable nature of subsurface conditions, resulting in high material consumption and environmental impacts. This project explores a fundamentally different strategy inspired by natural biomineralization systems, where proteins guide the formation and organization of minerals with high efficiency and precision. The research aims to enable strong bonding between soil particles using minimal amounts of binding material by promoting localized mineral formation at particle contact points. Advancing this concept could support the development of safer, more sustainable, and more resource-efficient infrastructure systems while reducing the environmental burdens associated with traditional ground improvement practices. The project will also integrate research with education through new interdisciplinary curriculum modules, hands-on laboratory activities, instructional videos, virtual reality learning tools, undergraduate research mentorship, industry engagement, and outreach activities for students and the public. These activities will help train a future workforce at the interface of biology and geotechnical engineering and expand participation in science and engineering education. The project investigates whether proteins can be identified or engineered to simultaneously bind to soil particle surfaces and calcium carbonate minerals, localize mineral precipitation at interparticle contacts, and improve the mechanical behavior of the resulting mineral bonds. Enzyme-induced carbonate precipitation through urea hydrolysis will serve as the model biocementation system. The research combines bioinformatics-guided protein identification, phage display screening, recombinant protein engineering, and fusion protein design to discover dual-affinity proteins capable of functioning under chemically challenging soil treatment conditions. Microfluidic experiments, microscopy, Raman spectroscopy, X-ray diffraction, micro-computed tomography imaging, nanoindentation, and geotechnical laboratory testing will be used to investigate protein-mediated control of precipitation localization, crystal morphology, and soil mechanical behavior. Discrete element method simulations will further quantify how protein-enhanced interparticle bonding influences macroscale soil response. The project is expected to establish structure-function relationships linking protein characteristics to precipitation behavior and soil strengthening performance, thereby advancing a new molecularly guided framework for soil stabilization and sustainable biocementation technologies. 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.