A grant has been awarded to Drs. J. Gregory Zeikus and John W. Urbance of Michigan State University to establish an observatory for microbial electrophiles in marine sediments. The goals of the research are to enrich, isolate, and characterize the microbial populations that can either grow on electricity as the electron donor or generate electricity from natural energy sources found in sediments. Novel bioelectrochemical reactor systems containing specially designed metal-graphite electrodes will be filled with sediment and the redox potential will be carefully controlled by a potentiostat. After 2-5 weeks of incubations, the bacterial populations grown on the cathode or anode surfaces will be analyzed by high throughput rDNA sequencing and microscopy. Then, novel cathodophile and anodophiles will be isolated from the biofilms and characterized microbiologically.
They are testing the hypothesis that electrophiles are an important part of microbial diversity and that, based on the exact potential of the anode or cathode used in the enrichments, different populations will exist. Most of the extreme diversity of microbes has gone undiscovered because of lack of suitable enrichment and isolation techniques, which in part this project will provide. These studies may discover important new microbes for use in fuel cells, generation of electricity from waste treatment, or for the bioelectrosynthesis of chemicals, drugs, and fuels.
