Multipurpose Biosensors Rely on Luciferase to Light up Target Molecules

A team of Swiss molecular biologists developed a luminescent marker system that sends out a light signal after binding to a specific target molecule.

Investigators at Ecole Polytechnique Fédérale de Lausanne (Switzerland) attached a small chemical tag to the enzyme luciferase, which catalyzes the light produced by fireflies. The tag molecule prevented luciferase from producing light, but when the tag detected its target protein, it released luciferase and attached to that protein instead. As a result, luciferase was free to emit a light, which was the signal that the target molecule had been found.

As proof-of-principle the investigators described in the July 22, 2015, online edition of the journal Nature Communications a luciferase controlled by human carbonic anhydrase whose activity could be controlled by proteins or small molecules in vitro and on living cells, and novel fluorescent and bioluminescent biosensors.

"You can think of the tagged luciferase as a cyborg molecule," said senior author Dr. Kai Johnsson, professor of chemistry at Ecole Polytechnique Fédérale de Lausanne. "Half bio, half synthetic. How could you make luciferase sensitive to the presence of another protein just through mutations? It is a lot of work. With this chemical trick, all we have to worry about is designing an appropriate tag that can recognize the target protein. This is a generalized design. It shows how you can exploit synthetic chemistry to create sophisticated biosensor proteins."

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Ecole Polytechnique Fédérale de Lausanne