Projects
Research in the Gralnick lab

Electron Shuttling with Flavins

We are studying the molecular mechanism of respiratory pathways in Shewanella.  Our current focus is extracellular electron transfer pathways. Understanding how these pathways work may help us engineer strains that generate more power in microbial fuel cells, or have an increased reactivity against certain toxic metals in the environment.

We recently discovered that Shewanella use extracellular flavins to help mediate reduction of insoluble substrates through a process called redox shuttling. We are trying to understand how flavin excretion happens and how the process is regulated and what other roles extracellular flavins have in microbes.

Synthetic Biology in Environmental Bacteria

We are developing strains, tools and techniques for increasing the robustness of using Shewanella (and other microbes) for metabolic engineering and downstream applications in both Bioenergy (microbial fuel cells), Bioremediation and Biocatalysis. We are using Synthetic Biology to engineer new pathways into Shewanella and exploring the reversibility of electron transfer into the cells as a potential platform for Electrosynthesis.

Exploring Minnesota Microbes

Many unique sites for microbes exist in Minnesota. We have begun characterizing the Soudan Iron Mine in northern Minnesota, a 2.7 billion year old banded iron formation, where we have found some very interesting microbes. Our colleagues in the Department of Earth Sciences are excited about this ecosystem for a potential parallel with Mars. How cool is that?! Answer: very cool. (Pioneer Press Story Dec 22.pdf)

As part of the College of Biological Science’s Nature of Life Program we are also studying magnetotactic bacteria found in and around Lake Itasca - the headwaters of the Mississippi.