1. Structural and Functional Characterization of a Biliverdin-Binding Near-Infrared Fluorescent Protein From the Serpin Superfamily
- Author
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Agnidipta Ghosh, Kyrylo Yu. Manoilov, Steven C. Almo, Vladislav V. Verkhusha, Department of Anatomy, and Medicum
- Subjects
law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Bacterial Proteins ,Structural Biology ,law ,CCP4 SUITE ,medicine ,fluorescent protein ,Animals ,Humans ,Molecular Biology ,iRFP ,Serpins ,Fluorescent Dyes ,030304 developmental biology ,TOOLS ,0303 health sciences ,Biliverdin ,Phytochrome ,Chemistry ,Biliverdine ,biliprotein ,Chromophore ,Fluorescence ,Tetrapyrrole ,TRANSPORT ,Protease inhibitor (biology) ,3. Good health ,Luminescent Proteins ,Tetrapyrroles ,Biochemistry ,Recombinant DNA ,tetrapyrrole ,1182 Biochemistry, cell and molecular biology ,3111 Biomedicine ,030217 neurology & neurosurgery ,Function (biology) ,HeLa Cells ,medicine.drug - Abstract
Biliverdin-binding serpins (BBSs) are proteins that are responsible for coloration in amphibians and fluoresce in the near-infrared (NIR) spectral region. Here we produced the first functional recombinant BBS of the polka-dot treefrog Boana punctata (BpBBS), assembled with its biliverdin (BV) chromophore, and report its biochemical and photochemical characterization. We determined the crystal structure of BpBBS at 2.05 angstrom resolution, which demonstrated its structural homology to the mammalian protease inhibitor alpha-1-antitrypsin. BV interaction with BpBBS was studied and it was found that the N-terminal polypeptide (residues 19-50) plays a critical role in the BV binding. By comparing BpBBS with the available NIR fluorescent proteins and expressing it in mammalian cells, we demonstrated its potential as a NIR imaging probe. These results provide insight into the non-inhibitory function of serpins, provide a basis for improving their performance in mammalian cells, and suggest possible paths for the development of BBS-based fluorescent probes. (C) 2021 Elsevier Ltd. All rights reserved.
- Published
- 2022