What if…and “Using Bacteria to Send Secret Messages”

As described here, a team of researchers at Tufts University used E. coli strains modified with fluorescent proteins that glow in a range of seven colors to create a mechanism for transmitting secret messages. The researchers dubbed the system “Steganography by Printed Arrays of Microbes” or “SPAM” for short.

Each character can be encoded using two colors, creating 49 possible combinations: enough for 26 letters, digits 0-9, and a few symbols. The desired message is grown on agar plates then transferred to a thin film that can be delivered to someone. The film would appear blank until put in the proper growth medium. If the incorrect medium is used, the message would appear garbled. The researchers also believe you could create strains that would lose their fluorescence over time–a built-in self-destruct mechanism. But they note that the E. coli method could probably only transmit 500-1,000 characters per sheet of paper.

Researchers have previously shown that it was possible to create hidden messages in DNA, but the Tufts researchers claim their process is easier. A DNA cryptography researcher at the University of Duisburg-Essen, Germany believes sending an encrypted e-mail would be more effective than using E. coli. He notes that the DNA method is typically used to identify genetically modified organisms, not by spies. He also pointed out that sending genetically engineered bacteria through the mail would be illegal in many countries (completely overlooking the illegality of spying, I might point out).

I have to agree with the DNA researcher. What spy is going to travel with the necessary equipment to do this? Who travels with agar plates and bacteria growth medium? It seems far more troublesome than simply using dead drops, microdots, encrypted e-mails, or one-time pads. I don’t think SPAM will be used like the researchers envision. Then again, that could be said about quite a few inventions.

But what if SPAM was used as a sort of augmented reality device? Instead of chalk marks on a mailbox, say, what if people could post bits of film around town? What if a few spritzes of the right growth medium could reveal the message (e.g., “We need to meet,” “Dead drop activated,” or noting troop movements)? What if an underground group had a resident researcher who acted as a sort of E. coli scribe, printing up necessary messages for couriers to post in pre-determined locations? I think a chalk mark is easier, cheaper, and raises less suspicion, but it’s an interesting idea. I am curious to see where this technology ends up.

What do you think? How would you use this technology? For science? For spying? For art?