this is for the people who went through trauma and didn’t come out of it with thicker skin. but, instead, came back with sensitivity to the world and a deep sadness that won’t go away. some of us went through something and lost a piece of ourselves; our broken hearts never healed quite right afterwards. i see you and i feel you and i am you. it’s going to be okay.
Genetically Modified Bacteria Produce Energy From Wastewater
E. Coli is one of the most widely studied bacteria studied in academic research. Though most people probably associate it with food/water borne illness, most strains of E. Coli are completely harmless. They even occur naturally within your intestines. Now, scientists at EPFL have engineered a strain of E. Coli that can generate electricity.
The survival of bacteria depends on redox reactions. Bacteria use these reactions to interconvert chemicals in order to grow and metabolize. Since bacteria are an inexhaustible natural resource, many bacterial reactions have been industrially implemented, both for creating or consuming chemical substrates. For instance, you may have heard about researchers discovering bacteria that can break down and metabolize plastic, the benefits of which are obvious. Some of these bacterial reactions are anabolic, which means that they need to be provided external energy in order to carry it out, but others are catabolic, which means that the reactions actually create energy. Â
Some bacteria, such as Shewanella oneidensis, can create electricity as they metabolize. This could be useful to a number of green applications, such as bioelectricity generation from organic substrates, reductive extracellular synthesis of valuable products such as nanoparticles and polymers, degradation of pollutants for bioremediation, and bioelectronic sensing. However, electricity producing bacteria such as Shewanella oneidensis tend to be very specific. They need strict conditions in order to survive, and they only produce electricity in the presence of certain chemicals. Â
The method that Shewanella oneidensis uses to generate electricity is called extracellular electron transfer (EET). This means that the cell uses a pathway of proteins and iron compounds called hemes to transfer an electron out of the cell. Bacteria have an inner and outer cell membrane, so this pathway spans both of them, along with the periplasmic space between. In the past, scientists have tried to engineer hardier bacteria such as E. Coli with this electron-generating ability. It worked⊠a little bit. They were only able to create a partial EET pathway, so the amount of electricity generated was fairly small.
Now, the EPFL researchers have managed to create a full pathway and triple the amount of electricity that E. Coli can produce. âInstead of putting energy into the system to process organic waste, we are producing electricity while processing organic waste at the same time â hitting two birds with one stone!â says Boghossian, a professor at EPFL. âWe even tested our technology directly on wastewater that we collected from Les Brasseurs, a local brewery in Lausanne. The exotic electric microbes werenât even able to survive, whereas our bioengineered electric bacteria were able to flourish exponentially by feeding off this waste.â
This development is still in the early stages, but it could have exciting implications both in wastewater processing and beyond.
âOur work is quite timely, as engineered bioelectric microbes are pushing the boundaries in more and more real-world applicationsâ says Mouhib, the lead author of the manuscript. âWe have set a new record compared to the previous state-of-the-art, which relied only on a partial pathway, and compared to the microbe that was used in one of the biggest papers recently published in the field. With all the current research efforts in the field, we are excited about the future of bioelectric bacteria, and canât wait for us and others to push this technology into new scales.â
The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age.
