Structural evidence of thioacetate reduction by fluorescent protein mRuby.

Area of Science:

• Biochemistry and Biophysics
• Super-resolution Microscopy
• Green Chemistry

Background:

• Red fluorescent protein mRuby is crucial for super-resolution imaging.
• Understanding protein-compound interactions is key for developing new imaging tools.

Purpose of the Study:

• To investigate the effect of thioacetate on mRuby's optical properties.
• To elucidate the mechanism of thioacetate binding and photoreduction in mRuby.

Main Methods:

• Spectrophotometry to analyze absorption spectra changes.
• X-ray crystallography to determine structural binding sites.
• Atomic-resolution serial crystallography to capture dynamic photoreduction processes.

Main Results:

• Thioacetate addition caused a visible color change in mRuby solutions.
• Spectrophotometry revealed concentration-dependent spectral shifts.
• Crystallography confirmed thioacetate binding at the mRuby chromophore.
• Serial crystallography visualized step-by-step thioacetate photoreduction upon light exposure.

Conclusions:

• Thioacetate interaction with mRuby offers new insights into fluorophore-compound interactions.
• The observed photoreduction mechanism suggests potential for light-driven applications in green chemistry.
• This study enhances understanding of mRuby as a labeling tool and its response to chemical modification.