Bacteria Could be the Key to Biological ‘Wires’

Article:  “Electricity-conducting bacteria yield secret to tiny batteries, big medical advances”

Source:  Science Daily

Date Published:  April 4, 2019

Summary:  Scientists discovered that Geobacter sulfurreducens is conducting electricity through tiny fibers made of protein that “… surround a core of metal-containing molecules.”   It was previously thought that they were conducting electricity through pili, but new technology has made it possible to examine the smaller structures within the bacteria at a higher resolution.   These bacteria live in environments without oxygen, and they get rid of excess electrons almost as a way of ‘breathing.’   It is thought that this way of conducting electricity could eventually be harnessed and used in medical devices associated with human tissue.

Connections:  This article doesn’t relate exactly to the topics we have covered in class, but it does highlight how some bacteria have unique ways of processing molecules and electrons.   It mentions that these bacteria can also be used to clean up radioactive waste, which we have briefly talked about in class.

Critical Analysis:  I was not aware that bacteria could even conduct electricity, so the fact that they can do that, and people were able to figure out how they are doing it, is pretty cool.   It is also really interesting that the same technology the scientists used for this discovery was used to find a virus that was surviving in boiling acid.   The information seems scientifically accurate since they included quotes from the scientists that performed the research, and they included the citation for the article they were explaining.   I think the author did a good job of simplifying the material as best as they could so that any person could understand it.   It would be easier to understand if you were reading it with some background in biology, but it is not completely necessary to understand the basics of what they were talking about.

Question:  Will these proteins still function the same way if they are taken out of the bacteria and used for medical purposes?   Will the entire bacterium have to be used in the medical devices in order for them to work?

A2: Microbes in the News (#2)

How electricity-eating microbes use electrons to fix carbon dioxide (Science Daily)

Find the article  here.

Summary:   The bacterium, Rhodopseudomonas palustris, has been identified to have the ability to metabolize electricity. It transfers electrons to fix CO2 to fuel its growth. Essentially, it enjoys feasting on rust and uses the electrons in a process called extracellular electron uptake. The research team at Washington University are using this knowledge to understand the microbe’s role in carbon cycling and has helped connect some unknown areas of basic concepts.

An understanding of how these microbes store the electrons could potentially lead to the production of alternative biofuels.

Connection: The electron tower helped to visualize which compounds are metabolized by a microbe in question. We’ve also talked about the use of microbes in our everyday lives (probiotics, waste water treatment, immunizations, etc.), and could potentially lead to an alternative energy source if researchers discover the mechanisms to harness this microbe for bioplastics or biofuel (as mentioned in the article).

Critical Analysis: This could potentially lead to a great alternative source for fuels in the future.   It’s in its exploratory stages currently and much more about specific mechanisms needs to be learned before researchers are ready to turn it into biofuel.

The draw back of this type of approach poses the concern about how this application will alter the microbial world around us. Other fuels accumulate in the atmosphere so how will the accumulation of an organism affect our environment?


Question: How could the artificial abundance of this microbe affect the ecosystems around it?