Red light as the key to gene activity control

Recent developments show that appropriately configured bacteria can also play a role in the diagnosis and treatment of diseases. One promising method is the targeted activation of bacteria using red light, as this light can penetrate living tissue.

In order to realize these applications, a deep understanding of the molecular responses of bacteria to external stimuli such as light is necessary. The research team of the Photobiochemistry working group at the University of Bayreuth has made significant contributions to this. Their work shows how bacteria react to red light on a molecular level by adding or splitting off phosphate groups. These processes are often controlled by a two-component system consisting of a light-sensitive enzyme and a regulator.

The researchers at the University of Bayreuth, including Stefanie Meier and Prof. Andreas Möglich, have modified the two-component system to increase its sensitivity to red light. By replacing the light-sensitive unit, the system became ten times more sensitive to red light. The reason for this increased sensitivity lies in the altered activity of the phosphate groups: Under red light, the phosphate groups were cleaved off more quickly, inactivating the system even at lower red light intensities.

In addition, the researchers changed the length of the connection between the light-sensitive unit and the rest of the enzyme. These modifications led to contrasting properties in light regulation and signaling response at the genetic level compared to the original systems.

The newly developed variants with increased sensitivity and reprogrammed activity offer valuable tools for applications in synthetic biology and biotechnology. “The results obtained from this model system have general relevance for countless systems of this type, which regulate important bacterial responses such as development, movement and infectivity. In addition, we are creating systems that can be used directly in biotechnology, which allow the production of any proteins to be activated by red light,” explains Prof. Andreas Möglich.

The study was carried out in collaboration with the University of Jyväskylä, Finland, and was funded by the German Research Foundation and the EU project FET Open NEUROPA.

MEDICA-tradefair.com; Source: University of Bayreuth