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KillerOrange, a Genetically Encoded Photosensitizer Activated by Blue and Green Light

Karen S Sarkisyan1, Olga A Zlobovskaya1, Dmitry A Gorbachev1,2

  • 1Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia.

Plos One
|December 19, 2015
PubMed

Insights

Researchers developed KillerOrange, a novel photosensitizer protein. This optogenetic tool generates reactive oxygen species upon illumination, enabling targeted cell toxicity with chromatic orthogonality for advanced research applications.

Area of Science:

  • Biochemistry
  • Optogenetics
  • Molecular Biology

Background:

  • Genetically encoded photosensitizers are crucial optogenetic tools.
  • These proteins generate reactive oxygen species (ROS) upon light exposure.
  • Applications include cell ablation and protein inactivation.

Purpose of the Study:

  • To report a novel orange mutant of KillerRed, named KillerOrange.
  • To characterize its photosensitizing properties and tryptophan-based chromophore.
  • To demonstrate its utility in optogenetic applications.

Main Methods:

  • Development of an orange mutant of the red fluorescent protein KillerRed.
  • Illumination of bacterial and mammalian cells expressing KillerOrange with blue or green light.
  • Assessment of light-activated toxicity and chromatic orthogonality with KillerRed.

Main Results:

  • KillerOrange exhibits toxicity upon illumination with blue or green light.
  • It possesses a novel tryptophan-based chromophore.
  • KillerOrange functions independently and simultaneously with KillerRed.

Conclusions:

  • KillerOrange is a novel, genetically encoded photosensitizer.
  • It offers chromatic orthogonality for light-activated toxicity.
  • This tool expands optogenetic capabilities in diverse cell types.

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