The deeper we delve into science, the more we discover about ourselves – how we work and what extraordinary characteristics dwell within us. In fact, theories and experiments have uncovered a whole new world living within our own bodies. Minds in the gut, blood types that proclaim our prevalence to certain diseases and now, bacterial genomes, E. coli, that act as living memory recorders. It’s true, what we found can change the entire way we look at medicine, science and existence itself.
What we have found is a stable and fully erasable memory bank. That’s right, all we need to know about the environment and medicine can be found within a bacteria. Timothy Lu, associate professor of electrical engineering and computer science and biological engineering at MIT, discovered that we as human beings can store long-term information within our gut, using a bacterium. This bacteria can be placed in certain areas and later monitored to study quantitative information. Recently, limitations of existing methods of experimentation have been overcome, thus making room for unlimited storage space.
Timothy Lu partnered with Fahim Farzadfard, lead author of the journal Science, to expand on memory storage. Previous methods only allowed for storage of “all or nothing”. Now, an analog version reveals the amount of exposure and how much time the recording occupied. This whole process, in turn, allows for new information to be recorded into any bacterial DNA sequence.
How is memory stored?
In order to store memory in E. coli bacteria, MIT researchers programmed an enzyme which can insert DNA in a specific area of bacterial genomes. This DNA is then activated by light or some other predetermined molecule. Once the memory is stored, it can be passed on through vast generations of the bacterial genome.
When retrieving information from the genome, a number of processes could be used. One process involves inserting the DNA into a non-functioning area of the gene, sequencing the gene and revealing where the memory is stored. The quantity of cells in the gene were measured to determine how the exposure was implemented and how long it lasted. In one particular study, the system was used to detect light, a lactose metabolite called IPTG, and it was found to be compatible with other molecules or signals produced by cells.
Basically, instead of using one cell over and over as a storage device, an entire population of bacterial genomes can be used as an analog hard drive. Isn’t this exciting! Not only is the body filled with information, it can also store information for a very long time. This can help understand the environment, by monitoring pollution and carbon dioxide levels in the ocean. This knowledge can also benefit medicine, as an invaluable tool for health – monitoring dietary intake through the digestive system.
The bottom line
Using bacterial genomes as tape recorders has even higher implications. In the future, we can possible map diseases and link our biological memory banks to the ones we love. In fact, we are well on our way to accomplishing that feat as we speak. It seems, the deeper we delve into science, the more we appreciate life itself and our role in the universe.