Collaborative Proposal: INFEWS N/P/H2O: Supramolecular Recognition in the Biocatalytic Transformation of Organic Phosphorus-Containing Environmental Matrices

Cornell University, Ithaca NY

Investigators

Abstract

This project is funded by the Environmental Chemical Sciences program in the Division of Chemistry. It supports Dr. Ludmilla Aristilde of Cornell University and Dr. Deb Jaisi of the University of Delaware to investigate the cycling of phosphorus in the environment. Phosphorus (P) is an essential component of fertilizers, but in excess, a pollutant. Inorganic phosphorus is the form required by plants. Animals can use either organic or inorganic phosphorus. Both organic and inorganic phosphorus can be dissolved or suspended in water. The transformation of organic P to inorganic P is poorly understood. The key research objective is to better understand the chemical controls of this transformation. Outreach activities are carried out on the topic of the fate of organic P including fertilizers, organic wastes, and organic matter in soils. The outreach is aimed at increasing public literacy, from inner-city middle school students to farmers. Both investigators are involved in educational activities for farmers in New York and Delaware, respectively. Different stakeholders gain valuable knowledge regarding nutrient and fertilizer management on agricultural lands. This project applies a multidisciplinary approach. The research activities combine tools from molecular biology, analytical chemistry, and computational modeling. Molecular-level insights are obtained on the chemical factors that control the enzymatic release of inorganic P from complex organic assemblages. The project has three main objectives. First, it studies the activities of phosphatase enzymes with organic assemblages. Second, it addresses the effects of mineral surfaces on enzyme-substrate recognition. Third, the catalytic dynamics in response to external chemical stimuli is modeled. Metabolomics profiling enables the monitoring of catalytic hydrolysis of different organic P assemblages. Isotopes are used to track enzyme catalysis. This provides information on the role of different enzymes in recycling organic P in response to the chemistry of the environmental matrix. Molecular dynamics simulations in concert with the experimental studies illustrate the supramolecular framework responsible for the environmental biotransformation of organic P. The research findings shed light on how biogeochemical factors control phosphatase-mediated inorganic P generation from organic P assemblages. This addresses a long-standing knowledge gap in the environmental mapping of P species and their fate in soils and waters.