Optogenetic Control of Bacterial Expression by Red Light

Area of Science:

• Optogenetics
• Synthetic Biology
• Microbial Engineering

Background:

• Sensory photoreceptors control cellular processes via light.
• Bacteriophytochrome (BphP) photoreceptors use biliverdin to sense red/far-red light, switching between Pr and Pfr states.
• BphPs in two-component systems regulate gene expression via histidine kinase activity.

Purpose of the Study:

• Reprogram two blue-light bacterial gene expression systems for red-light control.
• Develop novel red-light-inducible systems for bacterial gene expression.
• Enable precise, spatially resolved gene regulation in bacteria using red light.

Main Methods:

• Applied insight from Deinococcus radiodurans BphP to reprogram gene expression systems.
• Engineered portable, single-plasmid systems (pREDusk and pREDawn) encoding all necessary components.
• Demonstrated red-light control of bacterial gene expression with high spatial resolution.

Main Results:

• Developed pREDusk and pREDawn systems for down- and up-regulation of gene expression, respectively.
• Achieved uniform gene expression control exceeding 100-fold under red light.
• Showcased single-cell level spatial resolution and multiplexing capabilities with other light colors.
• Demonstrated therapeutic potential with pREDawn triggering through material layers at safe light intensities.

Conclusions:

• pREDusk and pREDawn systems enable robust red-light-regulated gene expression in bacteria.
• The systems offer advantages in spatial resolution, multiplexing, and tissue penetration for diverse applications.
• Red-light control expands possibilities for optogenetics and synthetic biology in bacterial systems.