An engineered strain of Escherichia coli bacteria can turn wastewater into electricity at twice the efficiency of other state-of-the-art current-generating microbes.
Bacteria release energy in the process of breaking down and synthesizing organic compounds. Researchers can tap this source of electricity with tiny electrodes, raising the possibility of microbe-powered bioelectronics. But the bacterial species that are best at generating electricity tend to be picky about what substrates they will grow on. In contrast, E. coli will thrive just about anywhere: in the intestines, in food, in soil, and in water.
The bacterium can use a variety of different waste products as food sources, asserts Mohammed Mouhib, a doctoral student at École Polytechnique Fédérale de Lausanne (EPFL) and coauthor of the new study. “This enables us to feed wastewater we would otherwise discard to the E. coli, and gain energy back.”
To perfect E. coli for this purpose, Mouhib and his coauthors tested a variety of modifications to enhance the bacteria’s ability to move electrons across its layers of membranes. Some of these modifications were taken from E. coli’s standard metabolic processes, while others were borrowed from a bacterium called Shewanella oneidensis MR-1, which is naturally adept at shuffling ions around; this bacterium survives in low- to no-oxygen environments by reducing metals.
“E. coli...
Would you like to access the complete CEP News Update?
No problem. You just have to complete the following steps.
You have completed 0 of 2 steps.
-
Log in
You must be logged in to view this content. Log in now.
-
AIChE Membership
You must be an AIChE member to view this article. Join now.
Copyright Permissions
Would you like to reuse content from CEP Magazine? It’s easy to request permission to reuse content. Simply click here to connect instantly to licensing services, where you can choose from a list of options regarding how you would like to reuse the desired content and complete the transaction.
