Collaborative Research: MIM: The impact of the fungal microbiome in metal tolerance and soil biogeochemical transformations

Some metals are essential nutrients for life, while some are non-essential or even harmful to living organisms. Fungi and bacteria are microorganisms that often live in a close association and play a key role in transforming and detoxifying metals in the environment. In spite of this importance, there is relatively little understanding of how the interactions between bacteria and fungi influence the transformation and/or detoxification of metals.

The goal of this project is to address this knowledge gap by identifying how fungal-bacterial interactions affect metal transformation. This will be achieved through a novel multidisciplinary research approach employing advanced, state-of-the-science analytical techniques. Knowledge gained through this project will allow the engineered control of metal transformations for a wide range of applications in environmental cleanup, biorefining, production of nanoparticles, and other beneficial applications.

Successful completion of this research has strong potential to benefit society through improvements in environmental remediation and industrial manufacturing. This project will improve the Nation’s STEM workforce by providing a unique training opportunity for student researchers that bridges diverse fields such as environmental engineering, microbiology, geochemistry, bioinformatics, and art.

Remediation of metal contamination is a major environmental challenge because, unlike many organic pollutants, metal species cannot be degraded and can only be extracted or biotransformed to less toxic forms. While past approaches to biotransform metals have focused primarily on single microorganisms, host-microbiome interactions have shown potential to biotransform surrounding environments and improve host resiliency.

However, the mechanisms for metal biotransformation by microbial host-microbiome systems are largely unknown. The overall goal of this project is to elucidate the rules of life that govern fungal microbiomes. This goal will be achieved through a specific focus on fungal microbiomes, which include a fungal host, endosymbionts (endobacteria), and symbionts (exobacteria that live extracellularly) as a model host-microbiome system.

The specific research objectives of this project designed to achieve the goal are to: understand the effects of metals and metalloids on the diversity and transmission of fungal microbiomes (facultative and obligatory); and determine the role of fungal microbiomes in metal tolerance by mediating the uptake, transformation, and sorption of metal ions, nanoparticles, or other metal species. A deeply integrated multidisciplinary approach will be used to investigate physiological, genetic/genomic, and metabolic processes that govern the structure and function of fungal microbiomes in the presence of metals.

This will be achieved using novel state-of-the-science isotope probing, advanced microscopy, spectroscopy, and integrated genomics, transcriptomics, and metallomics to elucidate how the microbiome influences the metabolic activity of the host towards metal ions. Successful completion of this research has strong potential to identify new genes and/or pathways for metal tolerance and biotransformation, as well as expand our mechanistic understanding of the structure and function of fungal microbiomes in nature.

This knowledge has strong potential to benefit society by facilitating applications in remediation, water treatment, electronics manufacturing, antimicrobial production, medicine, and related fields.

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.