The researchers, Monica Ortiz, a doctoral candidate in bioengineering, and Drew Endy, PhD, an assistant professor of bioengineering, have parasitized the parasite and harnessed M13’s key attributes — its non-lethality and its ability to package and broadcast arbitrary DNA strands — to create what might be termed the biological Internet, or “Bi-Fi.” Their findings were published online Sept. 7 in the Journal of Biological Engineering.
M13 is a packager of genetic messages. It reproduces within its host, taking strands of DNA — strands that engineers can control — wrapping them up one by one and sending them out encapsulated within proteins produced by M13 that can infect other cells. Once inside the new hosts, they release the packaged DNA message.
The M13-based system is essentially a communication channel. It acts like a wireless Internet connection that enables cells to send or receive messages, but it does not care what secrets the transmitted messages contain.
“Effectively, we’ve separated the message from the channel. We can now send any DNA message we want to specific cells within a complex microbial community,” said Ortiz, the first author of the study.
It is well-known that cells naturally use various mechanisms, including chemicals, to communicate, but such messaging can be extremely limited in both complexity and bandwidth. Simple chemical signals are typically both message and messenger — two functions that cannot be separated.
“If your network connection is based on sugar then your messages are limited to ‘more sugar,’ ‘less sugar,’ or ‘no sugar’” explained Endy.
Cells engineered with M13 can be programmed to communicate in much more complex, powerful ways than ever before. The possible messages are limited only by what can be encoded in DNA and thus can include any sort of genetic instruction: start growing, stop growing, come closer, swim away, produce insulin and so forth.