Metal Ion Uptake in Lactobacillus Plantarum as a Model Organism for Studying the Human Gut Microbiota

The human body maintains a commensal relationship with millions of microbes, known as the microbiota. Most of these microbes are found in the gastrointestinal tract, where they digest food, take up nutrients, and protect the human body from pathogens. Changes in essential trace metal levels, including Mn2+, Zn2+, and Fe2+, influence the abundance of different types of microbial species and strongly correlate to altered infectious disease susceptibility. Despite recent efforts to map microbiota chemical functions, the role of metals in this area remains underdeveloped. Towards determining how different gut bacteria can tolerate changes in essential trace elements, we have developed gut bacteria culture methods for growth and quantified the metal ion uptake of Escherichia coli with inductively coupled plasma-mass spectrometry. We compared the growth of E. coli in Luria broth and A minimal media with limited trace metals. Then, we cultured Lactobacillus plantarum in De Man, Rogosa, and Sharpe (MRS) and chemically defined media with limited trace metals. Lastly, we categorized and identified possible metalloproteins using UniProt to better understand the metalloproteome of L. plantarum. This work will give us insight towards improvement and application of current therapies for gut diseases and potential targets for development of new therapeutics.