Eric Conners

Program: Plant and Microbial Biosciences

Current advisor: Arpita Bose, PhD

Undergraduate university: Allegheny College, 2016

Enrollment year: 2018

Research summary
Probing the interaction between phototrophic iron-oxidizing bacteria and solid-phase conductive substances, including semi-conductive minerals, and applying these lessons to develop sustainability solutions.

Photosynthetic iron oxidizing bacteria are among the oldest life on Earth. They are found in diverse environments including freshwater soils and sediments and industrial settings. They have played – and continue to play – an important role shaping Earth’s biogeochemistry though their influence on the cycling of elements like carbon, iron, and nitrogen. However, very little is known about the mechanisms these organisms use to thrive and survive. One of the more cryptic processes these bacteria employ is “extracellular electron transfer,” or EEU. EEU allows iron-oxidizing bacteria to capture electrons from soluble or insoluble electron donors, including solid-phase conductive substances like iron minerals. In the lab, EEU-capable bacteria can be grown on electrodes, which gives us an opportunity to explore the electrochemical reactions at the cell-surface interface with fine detail. Moreover, EEU is linked to photosynthetic CO2 fixation, meaning that these microbes use electrons acquired from sources such as iron minerals or poised electrodes to drive photosynthetic CO2 capture. This opens up a world of possibilities for exploring sustainable carbon capture. Beyond that, some of these organisms, including those studied by the Bose lab, are promising biochassis for producing biofuel and bioplastic. Altogether, this suggests a possible route for truly carbon-negative, sustainable carbon capture and utilization. The goal of my research is to explore photosynthetic EEU and CO2 capture in both environmental and biotechnological contexts. First, I will be investigating two novel chassis for bioplastic production, Rhodomicrobium vannielii and Rhodomicrobium udaipurense, both of which are EEU-capable photosynthetic iron-oxidizing bacteria. Then, I will investigate how they interact with biogenic iron oxy(hydrox)ides, which are a bioproduct of the iron-oxidation process.

Graduate publications
Conners EM, Rengasamy K, Bose A. 2022 Electroactive biofilms: how microbial electron transfer enables bioelectrochemical applications. J Ind Microbiol Biotechnol, 49(4)::kuac012

Conners EM, Davenport EJ, Bose A. 2021 Revised Draft Genome Sequences of Rhodomicrobium vannielii ATCC 17100 and Rhodomicrobium udaipurense JA643. Microbiol Resour Announc, 10(13):e00022-21. PMCID: PMC8104044