CAREER: Unraveling the Role of Bivalent Metals on Fungal Manganese Oxide Biomineralization Mechanisms

Metals are essential for the development and advancement of our society, but their presence in natural environments is a double-edged sword- acting as vital nutrients at low concentrations but becoming toxic at elevated levels. The concentrations of many metals in soils, sediments, and aquatic environments are controlled by biogeochemical processes involving manganese (Mn) oxides.

While microbial activities promoting Mn oxide formation in bacteria are well understood, the role of metals - particularly in fungi-mediated biomineralization – remains unclear. Despite fungi’s high abundance and metabolic activity, major knowledge gaps exist in our understanding of how they affect Mn oxide formation and how metals in return affect fungal biomineralization processes.

This project seeks to unravel the interactions between common bivalent metals, fungi, and biominerals, providing insights into bioremediation strategies and environmental metal cycling. In addition to its scientific contribution, the research will incorporate educational components to address issues of student recruitment and retention from diverse backgrounds in interdisciplinary fields within geoscience.

A comprehensive set of outreach activities will be developed to engage the public and students at multiple levels, emphasizing the importance of interdisciplinary geoscience research and its relevance to our environment.

Biogenic Mn oxides play an important role in metal cycling but the mechanisms of how metals affect fungal biomineralization remain poorly understood. The overall goal of this project is to elucidate the roles of common bivalent metals on the fungi-mediated Mn oxide biomineralization process, subsequent biomineral structure transformation, and bivalent metal sorption mechanisms.

A systematic approach will combine laboratory-based wet chemistry, advanced structural characterization of biominerals, and molecular biological techniques including proteomics and transcriptomics to identify the key reaction products involved in fungal Mn oxide biomineralization process. The proposed study will ultimately contribute to the development of cost-effective bioremediation strategies and inform models predicting metal cycling in natural settings.

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.