While some species of bacteria have been shown to generate electricity, these were considered to be more atypical organisms found in less immediate locales. New research has found that that several species of bacteria typically associated with the human gut also have this ability. This comes from research undertaken by the University of California, Berkeley. The research is important because it can offer insights into how bacteria infect us. It may also aid understanding of how some organisms assist us with maintaining a healthy gut.
Microbiologists have found, for example, that determined that Listeria monocytogenes, associated with food poisoning related to cold stored items, is capable of generating electricity. Moreover, the mechanism for electrical production differs from other species.
The research showed that Listeria are capable of transporting electrons through their cell wall into the environment in the form of tiny currents. As well as Listeria, it has been shown that other pathogenic organisms can generate electricity, such Clostridium perfringens; Enterococcus faecalis; and some of the streptococci can produce electricity.
These organisms share the characteristic of being morphologically categorized as Gram-positive bacteria, and they exist in a flavin-rich environment (Laboratory Roots explains that flavins are derived from vitamin B12). The human gut is a vitamin-rich ecological niche.
The reason why these organisms produce electricity is linked to the microbial metabolism and this process aids in energy production. To survive in anaerobic niches, like the human gut, all bacteria need to, in the absence of oxygen, need to find another molecule to accept the electrons. In the case of the electricity generators, this is a metal outside of the bacterial cell. The process of moving electrons outside of the cell involves several reactions (an extracellular electron transfer chain) which creates a small current.
According to lead researcher Professor Dan Portnoy: “The fact that so many bugs that interact with humans, either as pathogens or in probiotics or in our microbiota or involved in [the] fermentation of human products, are electrogenic — that had been missed before.”
The new insight into the physiology of the organisms have been reported to the journal Nature. The paper is titled “A flavin-based extracellular electron transfer mechanism in diverse Gram-positive bacteria.”
