Imagine what you might be able to do if you had a minuscule, color-coded construction kit composed of single cells you could stitch together any way you wanted to.
Stanford bioengineer Ingmar Riedel-Kruse, PhD, and his postdoc David Glass, PhD, have developed a set of tiny, synthetic molecular connectors that can be genetically engineered into bacteria so that they'll pop up on the bugs' surfaces. These molecular connectors have complementary shapes, like pieces of a jigsaw puzzle. So, any pair of the ordinarily free-swimming single-celled creatures, if they're sporting complementary connectors, wind up glomming on to each another.
By introducing different connector shapes (and sometimes more than one) into different bacteria, the scientists can get them to hook up together in programmable and predictable ways.
In a study published in Cell, Glass and Riedel-Kruse genetically color-coded various bacterial cells to correspond to whatever synthetic-connector shape they were displaying. For example, red cells contained a particular connector shape (or set of them) on their surfaces, blue cells had a different set of shapes, and green ones displayed still a third set of connectors. That allowed the researchers to toss the resulting cells into a mixture and see whether the emerging cell-cell assemblies tracked with the outcomes they'd predicted. (They did.)
The same technique, applied to human cells, could accelerate progress toward designing synthetic tissues and organs. Applied to bacteria, it could be be used to study biofilms, slimy carpets of adherent bacterial cells that stick to everything from your teeth to prosthetic implants and can be extremely resistant to antibiotics.
It could even be used to organize bacterial assembly lines — carefully ordered sequences of adjacent bacterial cells, each genetically engineered to carry out one step in a complicated chemical assembly process — for the production of exotic drugs, hormones, or industrial materials.
You could also form one heck of a conga line with these guys.
Image courtesy of Ingmar Riedel-Kruse