In a new study in PNAS, Stanford University's Jerome Bonnet, Pakpoom Subsoontorn, and Drew Endy say they've found a way to control bacterial genes, reports Scientific American's Ferris Jabr at the Observations blog. The team engineered E. coli to contain genes for both red and green fluorescent proteins, and they inserted an enzyme adapted from a bacteriophage to help them manipulate which colors the bacteria would display when exposed to ultraviolet light.
However in earlier work, the team found that they could flip the bacteria's switch only once. They have since found that by flooding the bacterial cells with either antibiotics or sugar molecules, they could activate different transcription factors and flip the promoter switch back and forth to produce either red or green light — it is a "rewriteable" way to store data in a cell, Jabr says.
"By replacing the genes for red and green fluorescent proteins with whatever genes they want to study — and subsequently flipping the RAD module promoter back and forth — other researchers can precisely control genes of interest," he adds.