CAREER: Advancing Biodegradation Through Protein Nanocompartment-Based Cargo Encapsulation for Organic Contaminant Removal

About This Grant

Many natural microorganisms, such as bacteria and fungi, can be used to degrade toxic pollutants and remediate contaminated sites. These microorganisms use a series of enzymes, called cascade enzymes, to break down pollutants step by step into less toxic end products. However, this process is slow and often allows toxic intermediates to accumulate. The goal of this CAREER project is to make biodegradation more efficient. The project will develop a new biotechnology, called protein nano-compartment (PNC)-based cargo encapsulation. Cascade enzymes will be encapsulated within PNCs, which will enable the enzymes to degrade pollutants and intermediates at similar rates. Toxic intermediates will not accumulate in the environment. The research will be integrated with education of students from middle schools and colleges. Successful completion of this project will create a more efficient, robust, and faster environmental remediation technology to protect human and environmental health. This CAREER project plans to apply PNC-based enzyme co-localization to accelerate biodegradation efficiency in removing organic water contaminants. The central hypothesis is that attaching enzymes with affinity tags of varying molecular properties will allow their tunable co-localization within PNCs, thereby enabling optimization and enhancement of the kinetics and stability of enzyme cascades for contaminant degradation. The study will integrate techniques in biodegradation, synthetic biology, and metabolic flux analysis to systematically characterize the effect of PNC co-localization on enzyme cascade efficiency. The proposed work will establish quantitative correlations between affinity tag properties and enzyme encapsulation efficiency. Building on these correlations, the study will explore how to strategically control the co-localization of biodegradative cascade enzymes within PNCs and analyze how this co-localization affects their kinetics in contaminant removal and stability against environmental factors under controlled in vitro conditions. Lastly, the PNC co-localization of biodegradative cascade enzymes will be assessed under cellular environments, and isotope-labeled metabolic flux analysis will be employed to develop a fundamental understanding of how the in vivo co-localization affects the rate, flux, and specificity of organic contaminant biodegradation in cells. The project includes an education plan aiming to 1) foster the education of college students in STEM and their participation in environmental engineering; 2) educate and train next-generation environmental engineers on the fundamentals, real-world applications, and opportunities of PNC encapsulation and biodegradation; and 3) promote public awareness and understanding of biodegradation as a sustainable solution for environmental protection and remediation. These educational activities will be integrated throughout to improve academic success and broaden participation of college students in research, stimulate STEM interest in 6-12 graders, train a future workforce on biodegradation through research projects, and build a biodegradation website for public education and outreach. 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.