1
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Jiang XX, Hou YN, Lu LW, Zhao KH. Monomeric Far-red and Near-infrared Fluorescent Biliproteins of Ultrahigh Brightness. Chembiochem 2024:e202400068. [PMID: 38623786 DOI: 10.1002/cbic.202400068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/01/2024] [Accepted: 04/15/2024] [Indexed: 04/17/2024]
Abstract
Far-red and near-infrared fluorescent proteins have regions of maximum transmission in most tissues and can be widely used as fluorescent biomarkers. We report that fluorescent phycobiliproteins originating from the phycobilisome core subunit ApcF2 can covalently bind biliverdin, named BDFPs. To further improve BDFPs, we conducted a series of studies. Firstly, we mutated K53Q and T144A of BDFPs to increase their effective brightness up to 190 % in vivo. Secondly, by homochromatic tandem fusion of high-brightness BDFPs to achieve monomerization, which increases the effective brightness by up to 180 % in vivo, and can effectively improve the labeling effect. By combining the above two approaches, the brightness of the tandem BDFPs was much improved compared with that of the previously reported fluorescent proteins in a similar spectral range. The tandem BDFPs were expressed stably while maintaining fluorescence in mammalian cells and Caenorhabditis elegans. They were also photostable and resistant to high temperature, low pH, and chemical denaturation. The tandem BDFPs advantages were proved in applications as biomarkers for imaging in super-resolution microscopy.
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Affiliation(s)
- Xiang-Xiang Jiang
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Ya-Nan Hou
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Li-Wen Lu
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Kai-Hong Zhao
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
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2
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Hou Y, Höppner A, Rao AG, Lahav Y, Kumar Das P, Ding W, Jiang X, Hu J, Schapiro I, Noy D, Zhao K. Control of a far‐red/near‐infrared spectral switch in an artificial fluorescent biliprotein derived from allophycocyanin. Protein Sci 2022. [DOI: 10.1002/pro.4412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ya‐Nan Hou
- State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan China
| | - Astrid Höppner
- Center for Structural Studies Heinrich‐Heine‐Universität Düsseldorf Germany
| | - Aditya G. Rao
- Fritz Haber Center for Molecular Dynamics Research, Institute for Chemistry The Hebrew University of Jerusalem Jerusalem Israel
| | - Yigal Lahav
- Fritz Haber Center for Molecular Dynamics Research, Institute for Chemistry The Hebrew University of Jerusalem Jerusalem Israel
- MIGAL‐Galilee Research Institute S. Industrial Zone Kiryat Shmona Israel
| | - Prabir Kumar Das
- MIGAL‐Galilee Research Institute S. Industrial Zone Kiryat Shmona Israel
| | - Wen‐Long Ding
- State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan China
| | - Xiang‐Xiang Jiang
- State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan China
| | - Ji‐Ling Hu
- State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan China
| | - Igor Schapiro
- Fritz Haber Center for Molecular Dynamics Research, Institute for Chemistry The Hebrew University of Jerusalem Jerusalem Israel
| | - Dror Noy
- MIGAL‐Galilee Research Institute S. Industrial Zone Kiryat Shmona Israel
- Faculty of Sciences and Technology Tel‐Hai Academic College Upper Galilee Israel
| | - Kai‐Hong Zhao
- State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan China
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3
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Hou YN, Ding WL, Jiang XX, Hu JL, Tan ZZ, Zhao KH. New Far-Red and Near-Infrared Fluorescent Phycobiliproteins with Excellent Brightness and Photostability. Chembiochem 2022; 23:e202200267. [PMID: 35811374 DOI: 10.1002/cbic.202200267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 07/10/2022] [Indexed: 11/11/2022]
Abstract
Far-red and near-infrared fluorescent proteins can be used as fluorescence biomarkers in the region of maximal transmission of most tissues and facilitate multiplexing. Recently, we reported the generation and properties of far-red and near-infrared fluorescent phycobiliproteins, termed BeiDou Fluorescent Proteins (BDFPs), which can covalently bind the more readily accessible biliverdin. Far-red BDFPs maximally fluoresce at ∼670 nm, while near-infrared BDFPs fluoresce at ∼710 nm. In this work, we molecularly evolved BDFPs as follows: (a) mutations L58Q, S68R and M81K of BDFPs, which can maximally enhance the effective brightness in vivo by 350 %; (b) minimization and monomerization of far-red BDFPs 2.1, 2.2, 2.3, and near-infrared BDFPs 2.4, 2.5 and 2.6. These newly developed BDFPs are remarkably brighter than the formerly reported far-red and near-infrared fluorescent proteins. Their advantages are demonstrated by biolabeling in mammalian cells using super-resolution microscopy.
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Affiliation(s)
- Ya-Nan Hou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Wen-Long Ding
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Xiang-Xiang Jiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Ji-Ling Hu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Zi-Zhu Tan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
| | - Kai-Hong Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P. R. China
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4
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Stepanenko OV, Kuznetsova IM, Turoverov KK, Stepanenko OV. Impact of Double Covalent Binding of BV in NIR FPs on Their Spectral and Physicochemical Properties. Int J Mol Sci 2022; 23:ijms23137347. [PMID: 35806351 PMCID: PMC9267011 DOI: 10.3390/ijms23137347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 02/01/2023] Open
Abstract
Understanding the photophysical properties and stability of near-infrared fluorescent proteins (NIR FPs) based on bacterial phytochromes is of great importance for the design of efficient fluorescent probes for use in cells and in vivo. Previously, the natural ligand of NIR FPs biliverdin (BV) has been revealed to be capable of covalent binding to the inherent cysteine residue in the PAS domain (Cys15), and to the cysteine residue introduced into the GAF domain (Cys256), as well as simultaneously with these two residues. Here, based on the spectroscopic analysis of several NIR FPs with both cysteine residues in PAS and GAF domains, we show that the covalent binding of BV simultaneously with two domains is the reason for the higher quantum yield of BV fluorescence in these proteins as a result of rigid fixation of the chromophore in their chromophore-binding pocket. We demonstrate that since the attachment sites are located in different regions of the polypeptide chain forming a figure-of-eight knot, their binding to BV leads to shielding of many sites of proteolytic degradation due to additional stabilization of the entire protein structure. This makes NIR FPs with both cysteine residues in PAS and GAF domains less susceptible to cleavage by intracellular proteases.
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5
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Nagano S, Sadeghi M, Balke J, Fleck M, Heckmann N, Psakis G, Alexiev U. Improved fluorescent phytochromes for in situ imaging. Sci Rep 2022; 12:5587. [PMID: 35379835 PMCID: PMC8980088 DOI: 10.1038/s41598-022-09169-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/14/2022] [Indexed: 12/18/2022] Open
Abstract
AbstractModern biology investigations on phytochromes as near-infrared fluorescent pigments pave the way for the development of new biosensors, as well as for optogenetics and in vivo imaging tools. Recently, near-infrared fluorescent proteins (NIR-FPs) engineered from biliverdin-binding bacteriophytochromes and cyanobacteriochromes, and from phycocyanobilin-binding cyanobacterial phytochromes have become promising probes for fluorescence microscopy and in vivo imaging. However, current NIR-FPs typically suffer from low fluorescence quantum yields and short fluorescence lifetimes. Here, we applied the rational approach of combining mutations known to enhance fluorescence in the cyanobacterial phytochrome Cph1 to derive a series of highly fluorescent variants with fluorescence quantum yield exceeding 15%. These variants were characterised by biochemical and spectroscopic methods, including time-resolved fluorescence spectroscopy. We show that these new NIR-FPs exhibit high fluorescence quantum yields and long fluorescence lifetimes, contributing to their bright fluorescence, and provide fluorescence lifetime imaging measurements in E.coli cells.
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6
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Tang K, Beyer HM, Zurbriggen MD, Gärtner W. The Red Edge: Bilin-Binding Photoreceptors as Optogenetic Tools and Fluorescence Reporters. Chem Rev 2021; 121:14906-14956. [PMID: 34669383 PMCID: PMC8707292 DOI: 10.1021/acs.chemrev.1c00194] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Indexed: 12/15/2022]
Abstract
This review adds the bilin-binding phytochromes to the Chemical Reviews thematic issue "Optogenetics and Photopharmacology". The work is structured into two parts. We first outline the photochemistry of the covalently bound tetrapyrrole chromophore and summarize relevant spectroscopic, kinetic, biochemical, and physiological properties of the different families of phytochromes. Based on this knowledge, we then describe the engineering of phytochromes to further improve these chromoproteins as photoswitches and review their employment in an ever-growing number of different optogenetic applications. Most applications rely on the light-controlled complex formation between the plant photoreceptor PhyB and phytochrome-interacting factors (PIFs) or C-terminal light-regulated domains with enzymatic functions present in many bacterial and algal phytochromes. Phytochrome-based optogenetic tools are currently implemented in bacteria, yeast, plants, and animals to achieve light control of a wide range of biological activities. These cover the regulation of gene expression, protein transport into cell organelles, and the recruitment of phytochrome- or PIF-tagged proteins to membranes and other cellular compartments. This compilation illustrates the intrinsic advantages of phytochromes compared to other photoreceptor classes, e.g., their bidirectional dual-wavelength control enabling instant ON and OFF regulation. In particular, the long wavelength range of absorption and fluorescence within the "transparent window" makes phytochromes attractive for complex applications requiring deep tissue penetration or dual-wavelength control in combination with blue and UV light-sensing photoreceptors. In addition to the wide variability of applications employing natural and engineered phytochromes, we also discuss recent progress in the development of bilin-based fluorescent proteins.
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Affiliation(s)
- Kun Tang
- Institute
of Synthetic Biology, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Hannes M. Beyer
- Institute
of Synthetic Biology, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
| | - Matias D. Zurbriggen
- Institute
of Synthetic Biology and CEPLAS, Heinrich-Heine-University
Düsseldorf, Universitätsstrasse
1, D-40225 Düsseldorf, Germany
| | - Wolfgang Gärtner
- Retired: Max Planck Institute
for Chemical Energy Conversion. At present: Institute for Analytical Chemistry, University
Leipzig, Linnéstrasse
3, 04103 Leipzig, Germany
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7
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Sakai K, Kondo Y, Fujioka H, Kamiya M, Aoki K, Goto Y. Near-infrared imaging in fission yeast using a genetically encoded phycocyanobilin biosynthesis system. J Cell Sci 2021; 134:273759. [PMID: 34806750 DOI: 10.1242/jcs.259315] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/09/2021] [Indexed: 11/20/2022] Open
Abstract
Near-infrared fluorescent protein (iRFP) is a bright and stable fluorescent protein with near-infrared excitation and emission maxima. Unlike the other conventional fluorescent proteins, iRFP requires biliverdin (BV) as a chromophore. Here, we report that phycocyanobilin (PCB) functions as a brighter chromophore for iRFP than BV, and that biosynthesis of PCB allows live-cell imaging with iRFP in the fission yeast Schizosaccharomyces pombe. We initially found that fission yeast cells did not produce BV and therefore did not show any iRFP fluorescence. The brightness of iRFP-PCB was higher than that of iRFP-BV both in vitro and in fission yeast. We introduced SynPCB2.1, a PCB biosynthesis system, into fission yeast, resulting in the brightest iRFP fluorescence. To make iRFP readily available in fission yeast, we developed an endogenous gene tagging system with iRFP and all-in-one integration plasmids carrying the iRFP-fused marker proteins together with SynPCB2.1. These tools not only enable the easy use of multiplexed live-cell imaging in fission yeast with a broader color palette, but also open the door to new opportunities for near-infrared fluorescence imaging in a wider range of living organisms. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Keiichiro Sakai
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Yohei Kondo
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Hiroyoshi Fujioka
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Mako Kamiya
- Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazuhiro Aoki
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
| | - Yuhei Goto
- Quantitative Biology Research Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Division of Quantitative Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan.,Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan
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8
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Hassan F, Khan FI, Song H, Lai D, Juan F. Effects of reverse genetic mutations on the spectral and photochemical behavior of a photoactivatable fluorescent protein PAiRFP1. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 228:117807. [PMID: 31806482 DOI: 10.1016/j.saa.2019.117807] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/29/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
Bacteriophytochrome photoreceptors (BphPs) containing biliverdin (BV) have great potential for the development of genetically engineered near-infrared fluorescent proteins (NIR FPs). We investigated a photoactivatable fluorescent protein PAiRFP1, was engineered through directed molecular evolution. The coexistence of both red light absorbing (Pr) and far-red light absorbing (Pfr) states in dark is essential for the photoactivation of PAiRFP1. The PCR based site-directed reverse mutagenesis, spectroscopic measurements and molecular dynamics (MD) simulations were performed on three targeted sites V386A, V480A and Y498H in PHY domain to explore their potential effects during molecular evolution of PAiRFP1. We found that these substitutions did not affect the coexistence of Pr and Pfr states but led to slight changes in the photophysical parameters. The covalent docking of biliverdin (cis and trans form) with PAiRFP1 was followed by several 100 ns MD simulations to provide some theoretical explanations for the coexistence of Pr and pfr states. The results suggested that experimentally observed coexistence of Pr and Pfr states in both PAiRFP1 and mutants were resulted from the improved stability of Pr state. The use of experimental and computational work provided useful understanding of Pr and Pfr states and the effects of these mutations on the photophysical properties of PAiRFP1.
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Affiliation(s)
- Fakhrul Hassan
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Faez Iqbal Khan
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China.
| | - Honghong Song
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Dakun Lai
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China.
| | - Feng Juan
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.
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9
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Matlashov ME, Shcherbakova DM, Alvelid J, Baloban M, Pennacchietti F, Shemetov AA, Testa I, Verkhusha VV. A set of monomeric near-infrared fluorescent proteins for multicolor imaging across scales. Nat Commun 2020; 11:239. [PMID: 31932632 PMCID: PMC6957686 DOI: 10.1038/s41467-019-13897-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 12/03/2019] [Indexed: 11/09/2022] Open
Abstract
Bright monomeric near-infrared (NIR) fluorescent proteins (FPs) are in high demand as protein tags for multicolor microscopy and in vivo imaging. Here we apply rational design to engineer a complete set of monomeric NIR FPs, which are the brightest genetically encoded NIR probes. We demonstrate that the enhanced miRFP series of NIR FPs, which combine high effective brightness in mammalian cells and monomeric state, perform well in both nanometer-scale imaging with diffraction unlimited stimulated emission depletion (STED) microscopy and centimeter-scale imaging in mice. In STED we achieve ~40 nm resolution in live cells. In living mice we detect ~105 fluorescent cells in deep tissues. Using spectrally distinct monomeric NIR FP variants, we perform two-color live-cell STED microscopy and two-color imaging in vivo. Having emission peaks from 670 nm to 720 nm, the next generation of miRFPs should become versatile NIR probes for multiplexed imaging across spatial scales in different modalities.
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Affiliation(s)
- Mikhail E Matlashov
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Jonatan Alvelid
- Department of Applied Physics and Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Mikhail Baloban
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Francesca Pennacchietti
- Department of Applied Physics and Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Anton A Shemetov
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, 10461, USA
| | - Ilaria Testa
- Department of Applied Physics and Science for Life Laboratory, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, 10461, USA. .,Medicum, Faculty of Medicine, University of Helsinki, 00029, Helsinki, Finland.
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10
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Stepanenko OV, Stepanenko OV, Shpironok OG, Fonin AV, Kuznetsova IM, Turoverov KK. Near-Infrared Markers based on Bacterial Phytochromes with Phycocyanobilin as a Chromophore. Int J Mol Sci 2019; 20:ijms20236067. [PMID: 31810174 PMCID: PMC6928796 DOI: 10.3390/ijms20236067] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 11/27/2019] [Accepted: 11/29/2019] [Indexed: 12/03/2022] Open
Abstract
Biomarkers engineered on the basis of bacterial phytochromes with biliverdin IXα (BV) cofactor as a chromophore are increasingly used in cell biology and biomedicine, since their absorption and fluorescence spectra lie within the so-called optical “transparency window” of biological tissues. However, the quantum yield of BV fluorescence in these biomarkers does not exceed 0.145. The task of generating biomarkers with a higher fluorescence quantum yield remains relevant. To address the problem, we proposed the use of phycocyanobilin (PCB) as a chromophore of biomarkers derived from bacterial phytochromes. In this work, we characterized the complexes of iRFP713 evolved from RpBphP2 and its mutant variants with different location of cysteine residues capable of covalent tetrapyrrole attachment with the PCB cofactor. All analyzed proteins assembled with PCB were shown to have a higher fluorescence quantum yield than the proteins assembled with BV. The iRFP713/V256C and iRFP713/C15S/V256C assembled with PCB have a particularly high quantum yield of 0.5 and 0.45, which exceeds the quantum yield of all currently available near-infrared biomarkers. Moreover, PCB has 4 times greater affinity for iRFP713/V256C and iRFP713/C15S/V256C proteins compared to BV. These data establish iRFP713/V256C and iRFP713/C15S/V256C assembled with the PCB chromophore as promising biomarkers for application in vivo. The analysis of the spectral properties of the tested biomarkers allowed for suggesting that the high-fluorescence quantum yield of the PCB chromophore can be attributed to the lower mobility of the D-ring of PCB compared to BV.
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Affiliation(s)
- Olesya V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
| | - Olga V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
| | - Olesya G. Shpironok
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
| | - Alexander V. Fonin
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
| | - Irina M. Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
| | - Konstantin K. Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russia; (O.V.S.); (O.V.S.); (O.G.S.); (A.V.F.); (I.M.K.)
- Peter the Great St. Petersburg Polytechnic University, Polytechnicheskaya str., 29, St. Petersburg 194064, Russia
- Correspondence: ; Tel.: +7-812-297-19-57
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11
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Physicochemical modeling of the phytochrome-mediated photothermal sensing. Sci Rep 2019; 9:10485. [PMID: 31324849 PMCID: PMC6642129 DOI: 10.1038/s41598-019-47019-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 07/09/2019] [Indexed: 11/08/2022] Open
Abstract
Light and temperature cues share many common signaling events towards plant photothermal morphogenesis. Particularly, the red (R)/far-red (FR)-absorbing phytochrome photoreceptors also function as temperature sensors, suggesting that light and temperature responses are intimately associated with each other. Here, we present data from physicochemical modeling of temperature sensing and thermomorphogenic patterning of hypocotyl growth, which illustrate that the two seemingly distinct stimulating cues are tightly coupled through physicochemical principles and temperature effects can be described as a function of infra-red (IR) thermal radiation. It is possible that the dark reversion from the FR-absorbing Pfr to the R-absorbing Pr phytochromes is essentially an IR-mediated thermal conversion. We propose that the phytochromes modulate photothermal responses by monitoring R:IR ratios, as they sense R:FR ratios during photomorphogenesis.
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12
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Karasev MM, Stepanenko OV, Rumyantsev KA, Turoverov KK, Verkhusha VV. Near-Infrared Fluorescent Proteins and Their Applications. BIOCHEMISTRY (MOSCOW) 2019; 84:S32-S50. [PMID: 31213194 DOI: 10.1134/s0006297919140037] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
High transparency, low light-scattering, and low autofluorescence of mammalian tissues in the near-infrared (NIR) spectral range (~650-900 nm) open a possibility for in vivo imaging of biological processes at the micro- and macroscales to address basic and applied problems in biology and biomedicine. Recently, probes that absorb and fluoresce in the NIR optical range have been engineered using bacterial phytochromes - natural NIR light-absorbing photoreceptors that regulate metabolism in bacteria. Since the chromophore in all these proteins is biliverdin, a natural product of heme catabolism in mammalian cells, they can be used as genetically encoded fluorescent probes, similarly to GFP-like fluorescent proteins. In this review, we discuss photophysical and biochemical properties of NIR fluorescent proteins, reporters, and biosensors and analyze their characteristics required for expression of these molecules in mammalian cells. Structural features and molecular engineering of NIR fluorescent probes are discussed. Applications of NIR fluorescent proteins and biosensors for studies of molecular processes in cells, as well as for tissue and organ visualization in whole-body imaging in vivo, are described. We specifically focus on the use of NIR fluorescent probes in advanced imaging technologies that combine fluorescence and bioluminescence methods with photoacoustic tomography.
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Affiliation(s)
- M M Karasev
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia. .,Medicum, University of Helsinki, Helsinki, 00290, Finland
| | - O V Stepanenko
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia.
| | - K A Rumyantsev
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia. .,Albert Einstein College of Medicine, Bronx, NY 10461, USA.,Loginov Moscow Clinical Scientific Center, Moscow, 111123, Russia
| | - K K Turoverov
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia. .,Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia
| | - V V Verkhusha
- Medicum, University of Helsinki, Helsinki, 00290, Finland. .,Albert Einstein College of Medicine, Bronx, NY 10461, USA
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13
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Zhao BQ, Ding WL, Tan ZZ, Tang QY, Zhao KH. A Large Stokes Shift Fluorescent Protein Constructed from the Fusion of Red Fluorescent mCherry and Far-Red Fluorescent BDFP1.6. Chembiochem 2019; 20:1167-1173. [PMID: 30609201 DOI: 10.1002/cbic.201800695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Indexed: 01/17/2023]
Abstract
Phycobiliproteins are constituents of phycobilisomes that can harvest orange, red, and far-red light for photosynthesis in cyanobacteria and red algae. Phycobiliproteins in the phycobilisome cores, such as allophycocyanins, absorb far-red light to funnel energy to the reaction centers. Therefore, allophycocyanin subunits have been engineered as far-red fluorescent proteins, such as BDFP1.6. However, most current fluorescent probes have small Stokes shifts, which limit their applications in multicolor bioimaging. mCherry is an excellent fluorescent protein that has maximal emittance in the red spectral range and a high fluorescence quantum yield, and thus, can be used as a donor for energy transfer to a far-red acceptor, such as BDFP1.6, by FRET. In this study, mCherry was fused with BDFP1.6, which resulted in a highly bright far-red fluorescent protein, BDFP2.0, with a large Stokes shift (≈79 nm). The excitation energy was absorbed maximally at 587 nm by mCherry and transferred to BDFP1.6 efficiently; thus emitting strong far-red fluorescence maximally at 666 nm. The effective brightness of BDFP2.0 in mammalian cells was 4.2-fold higher than that of iRFP670, which has been reported as the brightest far-red fluorescent protein. The large Stokes shift of BDFP2.0 facilitates multicolor bioimaging. Therefore, BDFP2.0 not only biolabels mammalian cells, including human cells, but also biolabels various intracellular components in dual-color imaging.
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Affiliation(s)
- Bao-Qing Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Wen-Long Ding
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Zi-Zhu Tan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Qi-Ying Tang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Kai-Hong Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, P.R. China
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14
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Gourinchas G, Etzl S, Winkler A. Bacteriophytochromes - from informative model systems of phytochrome function to powerful tools in cell biology. Curr Opin Struct Biol 2019; 57:72-83. [PMID: 30878713 DOI: 10.1016/j.sbi.2019.02.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/31/2019] [Accepted: 02/06/2019] [Indexed: 11/17/2022]
Abstract
Bacteriophytochromes are a subfamily of the diverse light responsive phytochrome photoreceptors. Considering their preferential interaction with biliverdin IXα as endogenous cofactor, they have recently been used for creating optogenetic tools and engineering fluorescent probes. Ideal absorption characteristics for the activation of bacteriophytochrome-based systems in the therapeutic near-infrared window as well the availability of biliverdin in mammalian tissues have resulted in tremendous progress in re-engineering bacteriophytochromes for diverse applications. At the same time, both the structural analysis and the functional characterization of diverse naturally occurring bacteriophytochrome systems have unraveled remarkable differences in signaling mechanisms and have so far only touched the surface of the evolutionary diversity within the family of bacteriophytochromes. This review highlights recent findings and future challenges.
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Affiliation(s)
- Geoffrey Gourinchas
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria
| | - Stefan Etzl
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria
| | - Andreas Winkler
- Institute of Biochemistry, Graz University of Technology, Petersgasse 12/II, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria.
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15
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Buhrke D, Tavraz NN, Shcherbakova DM, Sauthof L, Moldenhauer M, Vélazquez Escobar F, Verkhusha VV, Hildebrandt P, Friedrich T. Chromophore binding to two cysteines increases quantum yield of near-infrared fluorescent proteins. Sci Rep 2019; 9:1866. [PMID: 30755663 PMCID: PMC6372600 DOI: 10.1038/s41598-018-38433-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 12/27/2018] [Indexed: 12/16/2022] Open
Abstract
Phytochromes are red/far-red light sensing photoreceptors employing linear tetrapyrroles as chromophores, which are covalently bound to a cysteine (Cys) residue in the chromophore-binding domain (CBD, composed of a PAS and a GAF domain). Recently, near-infrared (NIR) fluorescent proteins (FPs) engineered from bacterial phytochromes binding biliverdin IXα (BV), such as the iRFP series, have become invaluable probes for multicolor fluorescence microscopy and in vivo imaging. However, all current NIR FPs suffer from relatively low brightness. Here, by combining biochemical, spectroscopic and resonance Raman (RR) assays, we purified and characterized an iRFP variant that contains a BV chromophore simultaneously bound to two cysteines. This protein with the unusual double-Cys attached BV showed the highest fluorescence quantum yield (FQY) of 16.6% reported for NIR FPs, whereas the initial iRFP appeared to be a mixture of species with a mean FQY of 11.1%. The purified protein was also characterized with 1.3-fold higher extinction coefficient that together with FQY resulted in almost two-fold brighter fluorescence than the original iRFP as isolated. This work shows that the high FQY of iRFPs with two cysteines is a direct consequence of the double attachment. The PAS-Cys, GAF-Cys and double-Cys attachment each entails distinct configurational constraints of the BV adduct, which can be identified by distinct RR spectroscopic features, i.e. the marker band including the C=C stretching coordinate of the ring A-B methine bridge, which was previously identified as being characteristic for rigid chromophore embedment and high FQY. Our findings can be used to rationally engineer iRFP variants with enhanced FQYs.
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Affiliation(s)
- David Buhrke
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Neslihan N Tavraz
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Luisa Sauthof
- Charité - Universitätsmedizin Berlin, Institute of Medical Physics and Biophysics (CC2), Group Protein X-ray Crystallography and Signal Transduction, Charitéplatz 1, 10117, Berlin, Germany
| | - Marcus Moldenhauer
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Francisco Vélazquez Escobar
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Peter Hildebrandt
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Thomas Friedrich
- Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
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16
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Oliinyk OS, Shemetov AA, Pletnev S, Shcherbakova DM, Verkhusha VV. Smallest near-infrared fluorescent protein evolved from cyanobacteriochrome as versatile tag for spectral multiplexing. Nat Commun 2019; 10:279. [PMID: 30655515 PMCID: PMC6336887 DOI: 10.1038/s41467-018-08050-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 12/12/2018] [Indexed: 01/07/2023] Open
Abstract
From a single domain of cyanobacteriochrome (CBCR) we developed a near-infrared (NIR) fluorescent protein (FP), termed miRFP670nano, with excitation at 645 nm and emission at 670 nm. This is the first CBCR-derived NIR FP evolved to efficiently bind endogenous biliverdin chromophore and brightly fluoresce in mammalian cells. miRFP670nano is a monomer with molecular weight of 17 kDa that is 2-fold smaller than bacterial phytochrome (BphP)-based NIR FPs and 1.6-fold smaller than GFP-like FPs. Crystal structure of the CBCR-based NIR FP with biliverdin reveals a molecular basis of its spectral and biochemical properties. Unlike BphP-derived NIR FPs, miRFP670nano is highly stable to denaturation and degradation and can be used as an internal protein tag. miRFP670nano is an effective FRET donor for red-shifted NIR FPs, enabling engineering NIR FRET biosensors spectrally compatible with GFP-like FPs and blue-green optogenetic tools. miRFP670nano unlocks a new source of diverse CBCR templates for NIR FPs.
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Affiliation(s)
- Olena S Oliinyk
- Medicum, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland
| | - Anton A Shemetov
- Department of Anatomy and Structural Biology, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Sergei Pletnev
- Basic Science Program, Macromolecular Crystallography Laboratory, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD, 21702, USA
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Vladislav V Verkhusha
- Medicum, Faculty of Medicine, University of Helsinki, 00290, Helsinki, Finland.
- Department of Anatomy and Structural Biology, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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17
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Ding WL, Hou YN, Tan ZZ, Jiang SP, Miao D, Losi A, Gärtner W, Scheer H, Zhao KH. Far-red acclimating cyanobacterium as versatile source for bright fluorescent biomarkers. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1649-1656. [DOI: 10.1016/j.bbamcr.2018.08.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/19/2018] [Accepted: 08/23/2018] [Indexed: 01/27/2023]
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18
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The Pathways of the iRFP713 Unfolding Induced by Different Denaturants. Int J Mol Sci 2018; 19:ijms19092776. [PMID: 30223568 PMCID: PMC6163377 DOI: 10.3390/ijms19092776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 09/11/2018] [Accepted: 09/13/2018] [Indexed: 02/06/2023] Open
Abstract
Near-infrared fluorescent proteins (NIR FPs) based on the complexes of bacterial phytochromes with their natural biliverdin chromophore are widely used as genetically encoded optical probes for visualization of cellular processes and deep-tissue imaging of cells and organs in living animals. In this work, we show that the steady-state and kinetic dependencies of the various spectral characteristics of iRFP713, developed from the bacterial phytochrome RpBphP2 and recorded at protein unfolding induced by guanidine hydrochloride (GdnHCl), guanidine thiocyanate (GTC), and urea, differ substantially. A study of the unfolding of three single-tryptophan mutant forms of iRFP713 expectedly revealed that protein unfolding begins with the dissociation of the native dimer, while the monomers remain compact. A further increase in the denaturant concentration leads to the formation of an intermediate state of iRFP713 having hydrophobic areas exposed on the protein surface (I). The total surface charge of iRFP713 (pI 5.86) changes from negative to positive with an increase in the concentration of GdnHCl and GTC because the negative charge of glutamic and aspartic acids is neutralized by forming salt bridges between the carboxyl groups and GdnH+ ions and because the guanidinium cations bind to amide groups of glutamines and asparagines. The coincidence of both the concentration of the denaturants at which the intermediate state of iRFP713 accumulates and the concentration of GdnH+ ions at which the neutralization of the surface charge of the protein in this state is ensured results in strong protein aggregation. This is evidently realized by iRFP713 unfolding by GTC. At the unfolding of the protein by GdnHCl, an intermediate state is populated at higher denaturant concentrations and a strong aggregation is not observed. As expected, protein aggregates are not formed in the presence of the urea. The aggregation of the protein upon neutralization of the charge on the macromolecule surface is the main indicator of the intermediate state of protein. The unfolded state of iRFP713, whose formation is accompanied by a significant decrease in the parameter A, was found to have a different residual structure in the denaturants used.
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19
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Gourinchas G, Heintz U, Winkler A. Asymmetric activation mechanism of a homodimeric red light-regulated photoreceptor. eLife 2018; 7:e34815. [PMID: 29869984 PMCID: PMC6005682 DOI: 10.7554/elife.34815] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 06/03/2018] [Indexed: 12/18/2022] Open
Abstract
Organisms adapt to environmental cues using diverse signaling networks. In order to sense and integrate light for regulating various biological functions, photoreceptor proteins have evolved in a modular way. This modularity is targeted in the development of optogenetic tools enabling the control of cellular events with high spatiotemporal precision. However, the limited understanding of signaling mechanisms impedes the rational design of innovative photoreceptor-effector couples. Here, we reveal molecular details of signal transduction in phytochrome-regulated diguanylyl cyclases. Asymmetric structural changes of the full-length homodimer result in a functional heterodimer featuring two different photoactivation states. Structural changes around the cofactors result in a quasi-translational rearrangement of the distant coiled-coil sensor-effector linker. Eventually, this regulates enzymatic activity by modulating the dimer interface of the output domains. Considering the importance of phytochrome heterodimerization in plant signaling, our mechanistic details of asymmetric photoactivation in a bacterial system reveal novel aspects of the evolutionary adaptation of phytochromes.
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Affiliation(s)
| | - Udo Heintz
- Max Planck Institute for Medical ResearchHeidelbergGermany
| | - Andreas Winkler
- Institute of Biochemistry, Graz University of TechnologyGrazAustria
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20
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Piatkevich KD, Suk HJ, Kodandaramaiah SB, Yoshida F, DeGennaro EM, Drobizhev M, Hughes TE, Desimone R, Boyden ES, Verkhusha VV. Near-Infrared Fluorescent Proteins Engineered from Bacterial Phytochromes in Neuroimaging. Biophys J 2017; 113:2299-2309. [PMID: 29017728 DOI: 10.1016/j.bpj.2017.09.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/03/2017] [Accepted: 09/06/2017] [Indexed: 11/17/2022] Open
Abstract
Several series of near-infrared (NIR) fluorescent proteins (FPs) were recently engineered from bacterial phytochromes but were not systematically compared in neurons. To fluoresce, NIR FPs utilize an enzymatic derivative of heme, the linear tetrapyrrole biliverdin, as a chromophore whose level in neurons is poorly studied. Here, we evaluated NIR FPs of the iRFP protein family, which were reported to be the brightest in non-neuronal mammalian cells, in primary neuronal culture, in brain slices of mouse and monkey, and in mouse brain in vivo. We applied several fluorescence imaging modes, such as wide-field and confocal one-photon and two-photon microscopy, to compare photochemical and biophysical properties of various iRFPs. The iRFP682 and iRFP670 proteins exhibited the highest brightness and photostability under one-photon and two-photon excitation modes, respectively. All studied iRFPs exhibited efficient binding of the endogenous biliverdin chromophore in cultured neurons and in the mammalian brain and can be readily applied to neuroimaging.
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Affiliation(s)
- Kiryl D Piatkevich
- Media Lab, MIT, Cambridge, Massachusetts; MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts
| | - Ho-Jun Suk
- Media Lab, MIT, Cambridge, Massachusetts; Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, Massachusetts
| | - Suhasa B Kodandaramaiah
- Media Lab, MIT, Cambridge, Massachusetts; MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts
| | - Fumiaki Yoshida
- MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts
| | - Ellen M DeGennaro
- MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts; Department of Brain and Cognitive Sciences, MIT, Cambridge, Massachusetts
| | - Mikhail Drobizhev
- Department of Cell Biology and Neuroscience, Montana State University, Bozeman, Montana
| | - Thomas E Hughes
- Department of Cell Biology and Neuroscience, Montana State University, Bozeman, Montana
| | - Robert Desimone
- MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts; Department of Brain and Cognitive Sciences, MIT, Cambridge, Massachusetts
| | - Edward S Boyden
- Media Lab, MIT, Cambridge, Massachusetts; MIT McGovern Institute for Brain Research, MIT, Cambridge, Massachusetts; Department of Brain and Cognitive Sciences, MIT, Cambridge, Massachusetts; Department of Biological Engineering, MIT, Cambridge, Massachusetts; MIT Center for Neurobiological Engineering, MIT, Cambridge, Massachusetts.
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York; Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York.
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21
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Ding WL, Miao D, Hou YN, Jiang SP, Zhao BQ, Zhou M, Scheer H, Zhao KH. Small monomeric and highly stable near-infrared fluorescent markers derived from the thermophilic phycobiliprotein, ApcF2. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1877-1886. [DOI: 10.1016/j.bbamcr.2017.08.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/13/2017] [Accepted: 08/02/2017] [Indexed: 01/05/2023]
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22
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Oliinyk OS, Chernov KG, Verkhusha VV. Bacterial Phytochromes, Cyanobacteriochromes and Allophycocyanins as a Source of Near-Infrared Fluorescent Probes. Int J Mol Sci 2017; 18:E1691. [PMID: 28771184 PMCID: PMC5578081 DOI: 10.3390/ijms18081691] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 07/28/2017] [Accepted: 07/28/2017] [Indexed: 12/21/2022] Open
Abstract
Bacterial photoreceptors absorb light energy and transform it into intracellular signals that regulate metabolism. Bacterial phytochrome photoreceptors (BphPs), some cyanobacteriochromes (CBCRs) and allophycocyanins (APCs) possess the near-infrared (NIR) absorbance spectra that make them promising molecular templates to design NIR fluorescent proteins (FPs) and biosensors for studies in mammalian cells and whole animals. Here, we review structures, photochemical properties and molecular functions of several families of bacterial photoreceptors. We next analyze molecular evolution approaches to develop NIR FPs and biosensors. We then discuss phenotypes of current BphP-based NIR FPs and compare them with FPs derived from CBCRs and APCs. Lastly, we overview imaging applications of NIR FPs in live cells and in vivo. Our review provides guidelines for selection of existing NIR FPs, as well as engineering approaches to develop NIR FPs from the novel natural templates such as CBCRs.
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Affiliation(s)
- Olena S Oliinyk
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, 00290 Helsinki, Finland.
| | - Konstantin G Chernov
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, 00290 Helsinki, Finland.
| | - Vladislav V Verkhusha
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, 00290 Helsinki, Finland.
- Department of Anatomy and Structural Biology, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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23
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Stepanenko OV, Stepanenko OV, Bublikov G, Kuznetsova I, Verkhusha V, Turoverov K. Stabilization of structure in near-infrared fluorescent proteins by binding of biliverdin chromophore. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2016.10.095] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Baloban M, Shcherbakova DM, Pletnev S, Pletnev VZ, Lagarias JC, Verkhusha VV. Designing brighter near-infrared fluorescent proteins: insights from structural and biochemical studies. Chem Sci 2017; 8:4546-4557. [PMID: 28936332 PMCID: PMC5590093 DOI: 10.1039/c7sc00855d] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 04/11/2017] [Indexed: 11/22/2022] Open
Abstract
Brighter near-infrared (NIR) fluorescent proteins (FPs) are required for multicolor microscopy and deep-tissue imaging. Here, we present structural and biochemical analyses of three monomeric, spectrally distinct phytochrome-based NIR FPs, termed miRFPs. The miRFPs are closely related and differ by only a few amino acids, which define their molecular brightness, brightness in mammalian cells, and spectral properties. We have identified the residues responsible for the spectral red-shift, revealed a new chromophore bound simultaneously to two cysteine residues in the PAS and GAF domains in blue-shifted NIR FPs, and uncovered the importance of amino acid residues in the N-terminus of NIR FPs for their molecular and cellular brightness. The novel chromophore covalently links the N-terminus of NIR FPs with their C-terminal GAF domain, forming a topologically closed knot in the structure, and also contributes to the increased brightness. Based on our studies, we suggest a strategy to develop spectrally distinct NIR FPs with enhanced brightness.
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Affiliation(s)
- Mikhail Baloban
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center , Albert Einstein College of Medicine , Bronx , New York 10461 , USA .
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center , Albert Einstein College of Medicine , Bronx , New York 10461 , USA .
| | - Sergei Pletnev
- Macromolecular Crystallography Laboratory , National Cancer Institute , Leidos Biomedical Research Inc. , Basic Research Program , Argonne , Illinois 60439 , USA
| | - Vladimir Z Pletnev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry , Russian Academy of Sciences , Moscow 117997 , Russian Federation
| | - J Clark Lagarias
- Department of Molecular and Cellular Biology , University of California in Davis , California 95616 , USA
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center , Albert Einstein College of Medicine , Bronx , New York 10461 , USA .
- Department of Biochemistry and Developmental Biology , Faculty of Medicine , University of Helsinki , Helsinki 00029 , Finland
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25
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Stepanenko OV, Stepanenko OV, Kuznetsova IM, Shcherbakova DM, Verkhusha VV, Turoverov KK. Interaction of Biliverdin Chromophore with Near-Infrared Fluorescent Protein BphP1-FP Engineered from Bacterial Phytochrome. Int J Mol Sci 2017; 18:E1009. [PMID: 28481303 PMCID: PMC5454922 DOI: 10.3390/ijms18051009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 04/30/2017] [Accepted: 05/04/2017] [Indexed: 11/17/2022] Open
Abstract
Near-infrared (NIR) fluorescent proteins (FPs) designed from PAS (Per-ARNT-Sim repeats) and GAF (cGMP phosphodiesterase/adenylate cyclase/FhlA transcriptional activator) domains of bacterial phytochromes covalently bind biliverdin (BV) chromophore via one or two Cys residues. We studied BV interaction with a series of NIR FP variants derived from the recently reported BphP1-FP protein. The latter was engineered from a bacterial phytochrome RpBphP1, and has two reactive Cys residues (Cys15 in the PAS domain and Cys256 in the GAF domain), whereas its mutants contain single Cys residues either in the PAS domain or in the GAF domain, or no Cys residues. We characterized BphP1-FP and its mutants biochemically and spectroscopically in the absence and in the presence of denaturant. We found that all BphP1-FP variants are monomers. We revealed that spectral properties of the BphP1-FP variants containing either Cys15 or Cys256, or both, are determined by the covalently bound BV chromophore only. Consequently, this suggests an involvement of the inter-monomeric allosteric effects in the BV interaction with monomers in dimeric NIR FPs, such as iRFPs. Likely, insertion of the Cys15 residue, in addition to the Cys256 residue, in dimeric NIR FPs influences BV binding by promoting the BV chromophore covalent cross-linking to both PAS and GAF domains.
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Affiliation(s)
- Olesya V Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russian.
| | - Olga V Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russian.
| | - Irina M Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russian.
- Department of Biophysics, Peter the Great St. Petersburg Polytechnic University, 29 Polytechnicheskaya st., St. Petersburg 195251, Russian.
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park ave., Bronx, NY 10461, USA.
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park ave., Bronx, NY 10461, USA.
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, 8 Haartmaninkatu st., Helsinki 00290, Finland.
| | - Konstantin K Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky ave., St. Petersburg 194064, Russian.
- Department of Biophysics, Peter the Great St. Petersburg Polytechnic University, 29 Polytechnicheskaya st., St. Petersburg 195251, Russian.
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Chernov KG, Redchuk TA, Omelina ES, Verkhusha VV. Near-Infrared Fluorescent Proteins, Biosensors, and Optogenetic Tools Engineered from Phytochromes. Chem Rev 2017; 117:6423-6446. [DOI: 10.1021/acs.chemrev.6b00700] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Konstantin G. Chernov
- Department
of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
| | - Taras A. Redchuk
- Department
of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
| | - Evgeniya S. Omelina
- Department
of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
| | - Vladislav V. Verkhusha
- Department
of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
- Department
of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York 10461, United States
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Hawley TS, Hawley RG, Telford WG. Fluorescent Proteins for Flow Cytometry. ACTA ACUST UNITED AC 2017; 80:9.12.1-9.12.20. [PMID: 28369764 DOI: 10.1002/cpcy.17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Fluorescent proteins have become standard tools for cell and molecular biologists. The color palette of fluorescent proteins spans the ultraviolet, visible, and near-infrared spectrum. Utility of fluorescent proteins has been greatly facilitated by the availability of compact and affordable solid state lasers capable of providing various excitation wavelengths. In theory, the plethora of fluorescent proteins and lasers make it easy to detect multiple fluorescent proteins simultaneously. However, in practice, heavy spectral overlap due to broad excitation and emission spectra presents a challenge. In conventional flow cytometry, careful selection of excitation wavelengths and detection filters is necessary. Spectral flow cytometry, an emerging methodology that is not confined by the "one color, one detector" paradigm, shows promise in the facile detection of multiple fluorescent proteins. This chapter provides a synopsis of fluorescent protein development, a list of commonly used fluorescent proteins, some practical considerations and strategies for detection, and examples of applications. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Teresa S Hawley
- Flow Cytometry Core Facility, Laboratory of Genome Integrity, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Robert G Hawley
- Department of Anatomy and Regenerative Biology, George Washington University School of Medicine and Health Sciences, Washington, D.C
| | - William G Telford
- Flow Cytometry Core Facility, Experimental Transplantation and Immunology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Hontani Y, Shcherbakova DM, Baloban M, Zhu J, Verkhusha VV, Kennis JTM. Bright blue-shifted fluorescent proteins with Cys in the GAF domain engineered from bacterial phytochromes: fluorescence mechanisms and excited-state dynamics. Sci Rep 2016; 6:37362. [PMID: 27857208 PMCID: PMC5114657 DOI: 10.1038/srep37362] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 10/25/2016] [Indexed: 11/21/2022] Open
Abstract
Near-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes (BphPs) are of great interest for in vivo imaging. They utilize biliverdin (BV) as a chromophore, which is a heme degradation product, and therefore they are straightforward to use in mammalian tissues. Here, we report on fluorescence properties of NIR FPs with key alterations in their BV binding sites. BphP1-FP, iRFP670 and iRFP682 have Cys residues in both PAS and GAF domains, rather than in the PAS domain alone as in wild-type BphPs. We found that NIR FP variants with Cys in the GAF or with Cys in both PAS and GAF show blue-shifted emission with long fluorescence lifetimes. In contrast, mutants with Cys in the PAS only or no Cys residues at all exhibit red-shifted emission with shorter lifetimes. Combining these results with previous biochemical and BphP1-FP structural data, we conclude that BV adducts bound to Cys in the GAF are the origin of bright blue-shifted fluorescence. We propose that the long fluorescence lifetime follows from (i) a sterically more constrained thioether linkage, leaving less mobility for ring A than in canonical BphPs, and (ii) that π-electron conjugation does not extend on ring A, making excited-state deactivation less sensitive to ring A mobility.
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Affiliation(s)
- Yusaku Hontani
- Department of Physics and Astronomy, VU University Amsterdam, Amsterdam 1081 HV, The Netherlands
| | - Daria M Shcherbakova
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | - Mikhail Baloban
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA
| | - Jingyi Zhu
- Department of Physics and Astronomy, VU University Amsterdam, Amsterdam 1081 HV, The Netherlands
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA.,Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki 00290, Finland
| | - John T M Kennis
- Department of Physics and Astronomy, VU University Amsterdam, Amsterdam 1081 HV, The Netherlands
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Near-infrared bioluminescent proteins for two-color multimodal imaging. Sci Rep 2016; 6:36588. [PMID: 27833162 PMCID: PMC5105121 DOI: 10.1038/srep36588] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/17/2016] [Indexed: 12/29/2022] Open
Abstract
Bioluminescence imaging became a widely used technique for noninvasive study of biological processes in small animals. Bioluminescent probes with emission in near-infrared (NIR) spectral region confer the advantage of having deep tissue penetration capacity. However, there are a very limited number of currently available luciferases that exhibit NIR bioluminescence. Here, we engineered two novel chimeric probes based on RLuc8 luciferase fused with iRFP670 and iRFP720 NIR fluorescent proteins. Due to an intramolecular bioluminescence resonance energy transfer (BRET) between RLuc8 and iRFPs, the chimeric luciferases exhibit NIR bioluminescence with maxima at 670 nm and 720 nm, respectively. The 50 nm spectral shift between emissions of the two iRFP chimeras enables combined multicolor bioluminescence imaging (BLI) and the respective multicolor fluorescence imaging (FLI) of the iRFPs. We show that for subcutaneously implanted cells, NIR bioluminescence provided a 10-fold increase in sensitivity compared to NIR FLI. In deep tissues, NIR BLI enabled detection of as low as 104 cells. Both BLI and FLI allowed monitoring of tumor growth and metastasis from early to late stages. Multimodal imaging, which combines concurrent BLI and FLI, provides continuous spatiotemporal analysis of metastatic cells in animals, including their localization and quantification.
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Liu C, Gong X, Lin R, Liu F, Chen J, Wang Z, Song L, Chu J. Advances in Imaging Techniques and Genetically Encoded Probes for Photoacoustic Imaging. Am J Cancer Res 2016; 6:2414-2430. [PMID: 27877244 PMCID: PMC5118604 DOI: 10.7150/thno.15878] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 05/31/2016] [Indexed: 11/05/2022] Open
Abstract
Photoacoustic (PA) imaging is a rapidly emerging biomedical imaging modality that is capable of visualizing cellular and molecular functions with high detection sensitivity and spatial resolution in deep tissue. Great efforts and progress have been made on the development of various PA imaging technologies with improved resolution and sensitivity over the past two decades. Various PA probes with high contrast have also been extensively developed, with many important biomedical applications. In comparison with chemical dyes and nanoparticles, genetically encoded probes offer easier labeling of defined cells within tissues or proteins of interest within a cell, have higher stability in vivo, and eliminate the need for delivery of exogenous substances. Genetically encoded probes have thus attracted increasing attention from researchers in engineering and biomedicine. In this review, we aim to provide an overview of the existing PA imaging technologies and genetically encoded PA probes, and describe further improvements in PA imaging techniques and the near-infrared photochromic protein BphP1, the most sensitive genetically encoded probe thus far, as well as the potential biomedical applications of BphP1-based PA imaging in vivo.
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Yuan C, Li HZ, Tang K, Gärtner W, Scheer H, Zhou M, Zhao KH. Near infrared fluorescent biliproteins generated from bacteriophytochrome AphB of Nostoc sp. PCC 7120. Photochem Photobiol Sci 2016; 15:546-53. [PMID: 27004456 DOI: 10.1039/c5pp00442j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The genome of the cyanobacterium Nostoc sp. PCC 7120 encodes a large number of putative bacteriophytochrome and cyanobacteriochrome photoreceptors that, due to their long-wavelength absorption and fluorescence emission, might serve as fluorescent tags in intracellular investigations. We show that the PAS-GAF domain of the bacteriophytochrome, AphB, binds biliverdin covalently and exhibits, besides its reversible photochemistry, a moderate fluorescence in the near infrared (NIR) spectral region. It was selected for further increasing the brightness while retaining the NIR fluorescence. In the first step, amino acids assumed to improve fluorescence were selectively mutated. The resulting variants were then subjected to several rounds of random mutagenesis and screened for enhanced fluorescence in the NIR. The brightness of optimized PAS-GAF variants increased more than threefold compared to that of wt AphB(1-321), with only insignificant spectral shifts (Amax around 695 nm, and Fmax around 720 nm). In general, the brightness increases with decreasing wavelengths, which allows for a selection of the fluorophore depending on the optical properties of the tissue. A spectral heterogeneity was observed when residue His260, located in close proximity to the chromophore, was mutated to Tyr, emphasizing the strong effects of the environment on the electronic properties of the bound biliverdin chromophore.
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Affiliation(s)
- Che Yuan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, P.R. China.
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