Natural Bacterial Immune System has been converted into the World’s Smallest Data Recorder by researchers at the Columbia University Medical Centre (CUMC) in the U.S., laying the groundwork for a new class of technologies that use bacterial cells for everything from disease diagnosis to environmental monitoring. Scientists taking advantage of immune system ‘memory’ modified an ordinary laboratory strain of the ubiquitous human gut microbe Escherichia coli, enabling the bacteria to record their interactions with the environment and time-stamp the events.
Environmental Sensing and basic studies in Ecology and Microbiology could be the other applications, where bacteria could monitor otherwise invisible changes without disrupting their surroundings, according to a study published in Science by Harris Wang, PhD, assistant professor in the Departments of Pathology & Cell Biology and Systems Biology at CUMC.
Harris Wang and his team modified a specific strain of Escherichia coli, a kind of bacteria that naturally occurs in the intestines, to allow the organisms to record their interactions in their environment, and tell the specific dates and times such interactions occur. The team used the CRISPR-Cas gene-editing system to create a Biological Tape Recorder.
- CRISPR-Cas system is a natural biological memory device. From an engineering perspective that’s actually quite nice, because it’s already a system that has been honed through evolution to be really great at storing information.
- CRISPR-Cas functions as the database of the body, documenting all past pathogen attacks and then copies the DNA of invading viruses so that any new bacteria can more effectively fight pathogens.
- CRISPR locus of the bacterial genome gathers and stores chronological records of the bacterial viruses that have survived, along with its ancestors and then becomes more efficient at recognizing and cutting down the same viruses, should they try to attack again.
- When those same viruses try to infect again, the CRISPR-Cas system can recognise and eliminate them.
To build their microscopic recorder, the researchers modified a piece of DNA called a plasmid, giving it the ability to create more copies of itself in the bacterial cell in response to an external signal.
According to the researchers, when this hacked bacteria is swallowed by a patient, they can then record any changes that take place in the digestive tract, and document any and all unprecedented views of things that have been previously inaccessible. The modified bacteria may likewise monitor changes in the surrounding areas without any disruptions.
There has been a growing body of evidence linking gut bacteria with several body conditions. In 2016 a research showed an association between gut bacteria and Parkinson’s disease. Gut bacteria has also been linked to other conditions such as chronic fatigue and multiple sclerosis. Since there are so many possible connections between gut bacteria and diseases, these new tools and methods can analyse the complexity of the stomach and intestines in order to provide invaluable data for medical purposes.