Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

0554176 - FZÚ 2022 RIV GB eng J - Journal Article
Hontani, Y. - Baloban, M. - Velazquez Escobar, F. - Jansen, S. A. - Shcherbakova, D. M. - Weissenborn, J. - Kloz, Miroslav - Mroginski, M. A. - Verkhusha, V. V. - Kennis, J.T.M.
Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome.
Communications Chemistry. Roč. 4, č. 1 (2021), č. článku 3. ISSN 2399-3669. E-ISSN 2399-3669
Research Infrastructure: ELI Beamlines III - 90141
Institutional support: RVO:68378271
Keywords : infrared fluorescent proteins * model compounds * chromophore * bacteriophytochrome * spectroscopy * reveals * state * photochemistry * optimization * insights
OECD category: Biophysics
Impact factor: 7.211, year: 2021
Method of publishing: Open access

Near-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes are widely used for structural and functional deep-tissue imaging in vivo. To fluoresce, NIR FPs covalently bind a chromophore, such as biliverdin IXa tetrapyrrole. The efficiency of biliverdin binding directly affects the fluorescence properties, rendering understanding of its molecular mechanism of major importance. miRFP proteins constitute a family of bright monomeric NIR FPs that comprise a Per-ARNT-Sim (PAS) and cGMP-specific phosphodiesterases - Adenylyl cyclases - FhlA (GAF) domain. Here, we structurally analyze biliverdin binding to miRFPs in real time using time-resolved stimulated Raman spectroscopy and quantum mechanics/molecular mechanics (QM/MM) calculations. Biliverdin undergoes isomerization, localization to its binding pocket, and pyrrolenine nitrogen protonation in <1min, followed by hydrogen bond rearrangement in similar to 2min.
Permanent Link: http://hdl.handle.net/11104/0328811