1
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Roterman I, Stapor K, Konieczny L. Transmembrane proteins-Different anchoring systems. Proteins 2024; 92:593-609. [PMID: 38062872 DOI: 10.1002/prot.26646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 11/03/2023] [Accepted: 11/17/2023] [Indexed: 04/13/2024]
Abstract
Transmembrane proteins are active in amphipathic environments. To stabilize the protein in such surrounding the exposure of hydrophobic residues on the protein surface is required. Transmembrane proteins are responsible for the transport of various molecules. Therefore, they often represent structures in the form of channels. This analysis focused on the stability and local flexibility of transmembrane proteins, particularly those related to their biological activity. Different forms of anchorage were identified using the fuzzy oil-drop model (FOD) and its modified form, FOD-M. The mainly helical as well as β-barrel structural forms are compared with respect to the mechanism of stabilization in the cell membrane. The different anchoring system was found to stabilize protein molecules with possible local fluctuation.
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Affiliation(s)
- Irena Roterman
- Department of Bioinformatics and Telemedicine, Jagiellonian University-Medical College, Krakow, Poland
| | - Katarzyna Stapor
- Faculty of Automatic, Electronics and Computer Science, Department of Applied Informatics, Silesian University of Technology, Gliwice, Poland
| | - Leszek Konieczny
- Chair of Medical Biochemistry, Jagiellonian University-Medical College, Krakow, Poland
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2
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Vlasova AD, Bukhalovich SM, Bagaeva DF, Polyakova AP, Ilyinsky NS, Nesterov SV, Tsybrov FM, Bogorodskiy AO, Zinovev EV, Mikhailov AE, Vlasov AV, Kuklin AI, Borshchevskiy VI, Bamberg E, Uversky VN, Gordeliy VI. Intracellular microbial rhodopsin-based optogenetics to control metabolism and cell signaling. Chem Soc Rev 2024; 53:3327-3349. [PMID: 38391026 DOI: 10.1039/d3cs00699a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Microbial rhodopsin (MRs) ion channels and pumps have become invaluable optogenetic tools for neuroscience as well as biomedical applications. Recently, MR-optogenetics expanded towards subcellular organelles opening principally new opportunities in optogenetic control of intracellular metabolism and signaling via precise manipulations of organelle ion gradients using light. This new optogenetic field expands the opportunities for basic and medical studies of cancer, cardiovascular, and metabolic disorders, providing more detailed and accurate control of cell physiology. This review summarizes recent advances in studies of the cellular metabolic processes and signaling mediated by optogenetic tools targeting mitochondria, endoplasmic reticulum (ER), lysosomes, and synaptic vesicles. Finally, we discuss perspectives of such an optogenetic approach in both fundamental and applied research.
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Affiliation(s)
- Anastasiia D Vlasova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Siarhei M Bukhalovich
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Diana F Bagaeva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Aleksandra P Polyakova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Nikolay S Ilyinsky
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Semen V Nesterov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Fedor M Tsybrov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Andrey O Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Egor V Zinovev
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Anatolii E Mikhailov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Alexey V Vlasov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Alexander I Kuklin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Valentin I Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia
| | - Ernst Bamberg
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | - Vladimir N Uversky
- Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA.
| | - Valentin I Gordeliy
- Institut de Biologie Structurale Jean-Pierre Ebel, Université Grenoble Alpes-Commissariat à l'Energie Atomique et aux Energies Alternatives-CNRS, 38027 Grenoble, France.
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3
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Meng X, Ganapathy S, van Roemburg L, Post M, Brinks D. Voltage Imaging with Engineered Proton-Pumping Rhodopsins: Insights from the Proton Transfer Pathway. ACS PHYSICAL CHEMISTRY AU 2023; 3:320-333. [PMID: 37520318 PMCID: PMC10375888 DOI: 10.1021/acsphyschemau.3c00003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 08/01/2023]
Abstract
Voltage imaging using genetically encoded voltage indicators (GEVIs) has taken the field of neuroscience by storm in the past decade. Its ability to create subcellular and network level readouts of electrical dynamics depends critically on the kinetics of the response to voltage of the indicator used. Engineered microbial rhodopsins form a GEVI subclass known for their high voltage sensitivity and fast response kinetics. Here we review the essential aspects of microbial rhodopsin photocycles that are critical to understanding the mechanisms of voltage sensitivity in these proteins and link them to insights from efforts to create faster, brighter and more sensitive microbial rhodopsin-based GEVIs.
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Affiliation(s)
- Xin Meng
- Department
of Imaging Physics, Delft University of
Technology, 2628 CJ Delft, The
Netherlands
| | - Srividya Ganapathy
- Department
of Imaging Physics, Delft University of
Technology, 2628 CJ Delft, The
Netherlands
- Department
of Pediatrics & Cellular and Molecular Medicine, UCSD School of Medicine, La Jolla, California 92093, United States
| | - Lars van Roemburg
- Department
of Imaging Physics, Delft University of
Technology, 2628 CJ Delft, The
Netherlands
| | - Marco Post
- Department
of Imaging Physics, Delft University of
Technology, 2628 CJ Delft, The
Netherlands
| | - Daan Brinks
- Department
of Imaging Physics, Delft University of
Technology, 2628 CJ Delft, The
Netherlands
- Department
of Molecular Genetics, Erasmus University
Medical Center, 3015 GD Rotterdam, The Netherlands
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4
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Otomo A, Mizuno M, Inoue K, Kandori H, Mizutani Y. Protein dynamics of a light-driven Na + pump rhodopsin probed using a tryptophan residue near the retinal chromophore. Biophys Physicobiol 2023; 20:e201016. [PMID: 38362331 PMCID: PMC10865881 DOI: 10.2142/biophysico.bppb-v20.s016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 02/22/2023] [Indexed: 02/17/2024] Open
Abstract
Direct observation of protein structural changes during ion transport in ion pumps provides valuable insights into the mechanism of ion transport. In this study, we examined structural changes in the light-driven sodium ion (Na+) pump rhodopsin KR2 on the sub-millisecond time scale, corresponding with the uptake and release of Na+. We compared the ion-pumping activities and transient absorption spectra of WT and the W215F mutant, in which the Trp215 residue located near the retinal chromophore on the cytoplasmic side was replaced with a Phe residue. Our findings indicated that atomic contacts between the bulky side chain of Trp215 and the C20 methyl group of the retinal chromophore promote relaxation of the retinal chromophore from the 13-cis to the all-trans form. Since Trp215 is conserved in other ion-pumping rhodopsins, the present results suggest that this residue commonly acts as a mechanical transducer. In addition, we measured time-resolved ultraviolet resonance Raman (UVRR) spectra to show that the environment around Trp215 becomes less hydrophobic at 1 ms after photoirradiation and recovers to the unphotolyzed state with a time constant of around 10 ms. These time scales correspond to Na+ uptake and release, suggesting evolution of a transient ion channel at the cytoplasmic side for Na+ uptake, consistent with the alternating-access model of ion pumps. The time-resolved UVRR technique has potential for application to other ion-pumping rhodopsins and could provide further insights into the mechanism of ion transport.
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Affiliation(s)
- Akihiro Otomo
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
- Present address: Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, National Institutes of Natural Science, Okazaki, Aichi 444-8787, Japan
- Present address: Department of Functional Molecular Science, School of Physical Science, SOKENDAI, Hayama, Kanagawa 240-0193, Japan
| | - Misao Mizuno
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Keiichi Inoue
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Hideki Kandori
- Department of Life Chemistry, Graduate School of Science, Nagoya Institute of Technology, Nagoya, Aichi 466-8555, Japan
| | - Yasuhisa Mizutani
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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5
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Kataoka M. Structural studies of bacteriorhodopsin in BC era. Biophys Physicobiol 2023; 20:e201006. [PMID: 38362329 PMCID: PMC10865857 DOI: 10.2142/biophysico.bppb-v20.s006] [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: 12/23/2022] [Accepted: 01/17/2023] [Indexed: 01/19/2023] Open
Abstract
It marked half a century since the discovery of bacteriorhodopsin two years ago. On this occasion, I have revisited historically important diffraction studies of this membrane protein, based on my recollections. X-ray diffraction and electron diffraction, and electron microscopy, described the low-resolution structure of bacteriorhodopsin within the purple membrane. Neutron diffraction was effective to assign the helical regions in the primary structure with 7 rods revealed by low-resolution structure as well as to describe the retinal position. Substantial conformational changes upon light illumination were clarified by the structures of various photointermediates. Early trials of time-resolved studies were also introduced. Models for the mechanism of light-driven proton pump based on the low-resolution structural studies are also described. Significantly, they are not far from the today's understanding. I believe that the spirit of the early research scientists in this field and the essence of their studies, which constitute the foundations of the field, still actively fertilizes current membrane protein research.
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Affiliation(s)
- Mikio Kataoka
- Nara Institute of Science and Technology, Ikoma, Nara 630-0189, Japan
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6
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Application of direct electrometry in studies of microbial rhodopsins reconstituted in proteoliposomes. Biophys Rev 2022; 14:771-778. [PMID: 36124261 PMCID: PMC9481854 DOI: 10.1007/s12551-022-00986-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 07/15/2022] [Indexed: 01/21/2023] Open
Abstract
Microbial rhodopsins are the family of retinal-containing proteins that perform primarily the light-driven transmembrane ion transport and sensory functions. They are widely distributed in nature and can be used for optogenetic control of the cellular activities by light. Functioning of microbial rhodopsins results in generation of the transmembrane electric potential in response to a flash that can be measured by direct time-resolved electrometry. This method was developed by L. Drachev and his colleagues at the Belozersky Institute and successfully applied in the functional studies of microbial rhodopsins. First measurements were performed using bacteriorhodopsin from Halobacterium salinarum-the prototype member of the microbial retinal protein family. Later, direct electrometric studies were conducted with proteorhodopsin from Exiguobacterium sibiricum (ESR), the sodium pump from Dokdonia, and other proteins. They allowed detailed characterization of the charge transfer steps during the photocycle of microbial rhodopsins and provided new insights for profound understanding of their mechanism of action.
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7
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Archaeal Lipids Regulating the Trimeric Structure Dynamics of Bacteriorhodopsin for Efficient Proton Release and Uptake. Int J Mol Sci 2022; 23:ijms23136913. [PMID: 35805918 PMCID: PMC9278134 DOI: 10.3390/ijms23136913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/19/2022] [Accepted: 06/20/2022] [Indexed: 11/30/2022] Open
Abstract
S-TGA-1 and PGP-Me are native archaeal lipids associated with the bacteriorhodopsin (bR) trimer and contribute to protein stabilization and native dynamics for proton transfer. However, little is known about the underlying molecular mechanism of how these lipids regulate bR trimerization and efficient photocycling. Here, we explored the specific binding of S-TGA-1 and PGP-Me with the bR trimer and elucidated how specific interactions modulate the bR trimeric structure and proton release and uptake using long-term atomistic molecular dynamic simulations. Our results showed that S-TGA-1 and PGP-Me are essential for stabilizing the bR trimer and maintaining the coherent conformational dynamics necessary for proton transfer. The specific binding of S-TGA-1 with W80 and K129 regulates proton release on the extracellular surface by forming a “Glu-shared” model. The interaction of PGP-Me with K40 ensures proton uptake by accommodating the conformation of the helices to recruit enough water molecules on the cytoplasmic side. The present study results could fill in the theoretical gaps of studies on the functional role of archaeal lipids and could provide a reference for other membrane proteins containing similar archaeal lipids.
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8
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Brown LS. Light-driven proton transfers and proton transport by microbial rhodopsins - A biophysical perspective. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183867. [PMID: 35051382 DOI: 10.1016/j.bbamem.2022.183867] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/30/2021] [Accepted: 01/10/2022] [Indexed: 12/31/2022]
Abstract
In the last twenty years, our understanding of the rules and mechanisms for the outward light-driven proton transport (and underlying proton transfers) by microbial rhodopsins has been changing dramatically. It transitioned from a very detailed atomic-level understanding of proton transport by bacteriorhodopsin, the prototypical proton pump, to a confounding variety of sequence motifs, mechanisms, directions, and modes of transport in its newly found homologs. In this review, we will summarize and discuss experimental data obtained on new microbial rhodopsin variants, highlighting their contribution to the refinement and generalization of the ideas crystallized in the previous century. In particular, we will focus on the proton transport (and transfers) vectoriality and their structural determinants, which, in many cases, remain unidentified.
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Affiliation(s)
- Leonid S Brown
- Department of Physics and Biophysics Interdepartmental Group, University of Guelph, Ontario N1G 2W1, Canada.
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9
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Shigeta A, Otani Y, Miyasa R, Makino Y, Kawamura I, Okitsu T, Wada A, Naito A. Photoreaction Pathways of Bacteriorhodopsin and Its D96N Mutant as Revealed by in Situ Photoirradiation Solid-State NMR. MEMBRANES 2022; 12:membranes12030279. [PMID: 35323754 PMCID: PMC8949607 DOI: 10.3390/membranes12030279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/25/2022] [Accepted: 02/26/2022] [Indexed: 11/18/2022]
Abstract
Bacteriorhodopsin (BR) functions as a light-driven proton pump that transitions between different states during the photocycle, such as all-trans (AT; BR568) and 13-cis, 15-syn (CS; BR548) state and K, L, M1, M2, N, and O intermediates. In this study, we used in situ photoirradiation 13C solid-state NMR to observe a variety of photo-intermediates and photoreaction pathways in [20-13C]retinal-WT-BR and its mutant [20-13C, 14-13C]retinal-D96N-BR. In WT-BR, the CS state converted to the CS* intermediate under photoirradiation with green light at −20 °C and consequently converted to the AT state in the dark. The AT state converted to the N intermediate under irradiation with green light. In D96N-BR, the CS state was converted to the CS* intermediate at −30 °C and consequently converted to the AT state. Simultaneously, the AT state converted to the M and L intermediates under green light illumination at −30 °C and subsequently converted to the AT state in the dark. The M intermediate was directly excited to the AT state by UV light illumination. We demonstrated that short-lived photo-intermediates could be observed in a stationary state using in situ photoirradiation solid-state NMR spectroscopy for WT-BR and D96N-BR, enabling insight into the light-driven proton pump activity of BR.
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Affiliation(s)
- Arisu Shigeta
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
| | - Yuto Otani
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
| | - Ryota Miyasa
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
| | - Yoshiteru Makino
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
| | - Izuru Kawamura
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
- Correspondence: (I.K.); (A.N.)
| | - Takashi Okitsu
- Laboratory of Organic Chemistry for Life Science, Kobe Pharmaceutical University, 4-19-1 Motoyamakitamachi, Higashinada-ku, Kobe 658-8558, Japan; (T.O.); (A.W.)
| | - Akimori Wada
- Laboratory of Organic Chemistry for Life Science, Kobe Pharmaceutical University, 4-19-1 Motoyamakitamachi, Higashinada-ku, Kobe 658-8558, Japan; (T.O.); (A.W.)
| | - Akira Naito
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; (A.S.); (Y.O.); (R.M.); (Y.M.)
- Correspondence: (I.K.); (A.N.)
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10
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Dynamic Coupling of Tyrosine 185 with the Bacteriorhodopsin Photocycle, as Revealed by Chemical Shifts, Assisted AF-QM/MM Calculations and Molecular Dynamic Simulations. Int J Mol Sci 2021; 22:ijms222413587. [PMID: 34948384 PMCID: PMC8709120 DOI: 10.3390/ijms222413587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 11/23/2022] Open
Abstract
Aromatic residues are highly conserved in microbial photoreceptors and play crucial roles in the dynamic regulation of receptor functions. However, little is known about the dynamic mechanism of the functional role of those highly conserved aromatic residues during the receptor photocycle. Tyrosine 185 (Y185) is one of the highly conserved aromatic residues within the retinal binding pocket of bacteriorhodopsin (bR). In this study, we explored the molecular mechanism of its dynamic coupling with the bR photocycle by automated fragmentation quantum mechanics/molecular mechanics (AF-QM/MM) calculations and molecular dynamic (MD) simulations based on chemical shifts obtained by 2D solid-state NMR correlation experiments. We observed that Y185 plays a significant role in regulating the retinal cis–trans thermal equilibrium, stabilizing the pentagonal H-bond network, participating in the orientation switch of Schiff Base (SB) nitrogen, and opening the F42 gate by interacting with the retinal and several key residues along the proton translocation channel. Our findings provide a detailed molecular mechanism of the dynamic couplings of Y185 and the bR photocycle from a structural perspective. The method used in this paper may be applied to the study of other microbial photoreceptors.
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11
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Nakai H, Takemura T, Ono J, Nishimura Y. Quantum-Mechanical Molecular Dynamics Simulations on Secondary Proton Transfer in Bacteriorhodopsin Using Realistic Models. J Phys Chem B 2021; 125:10947-10963. [PMID: 34582194 DOI: 10.1021/acs.jpcb.1c06231] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bacteriorhodopsin (BR) transports a proton from intracellular to extracellular (EC) sites through five proton transfers. The second proton transfer is the release of an excess proton stored in BR into the EC medium, and an atomistic understanding of this whole process has remained unexplored due to its ubiquitous environment. Here, fully quantum mechanical (QM) molecular dynamics (MD) and metadynamics (MTD) simulations for this process were performed at the divide-and-conquer density-functional tight-binding level using realistic models (∼50000 and ∼20000 atoms) based on the time-resolved photointermediate structures from an X-ray free electron laser. Regarding the proton storage process, the QM-MD/MTD simulations confirmed the Glu-shared mechanism, in which an excess proton is stored between Glu194 and Glu204, and clarified that the activation occurs by localizing the proton at Glu204 in the photocycle. Furthermore, the QM-MD/MTD simulations elucidated a release pathway from Glu204 through Ser193 to the EC water molecules and clarified that the proton release starts at ∼250 μs. In the ubiquitous proton diffusion in the EC medium, the transient proton receptors predicted experimentally were assigned to carboxylates in Glu9 and Glu74. Large-scale QM-MD/MTD simulations beyond the conventional sizes, which provided the above findings and confirmations, were possible by adopting our Dcdftbmd program.
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Affiliation(s)
- Hiromi Nakai
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.,Waseda Research Institute for Science and Engineering (WISE), Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.,Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University, 1-30 Goryo-Ohara, Nishikyo-ku, Kyoto 615-8245, Japan
| | - Toshiaki Takemura
- Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan
| | - Junichi Ono
- Waseda Research Institute for Science and Engineering (WISE), Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.,Elements Strategy Initiative for Catalysts & Batteries (ESICB), Kyoto University, 1-30 Goryo-Ohara, Nishikyo-ku, Kyoto 615-8245, Japan
| | - Yoshifumi Nishimura
- Waseda Research Institute for Science and Engineering (WISE), Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan
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12
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Unusual features of the c-ring of F 1F O ATP synthases. Sci Rep 2019; 9:18547. [PMID: 31811229 PMCID: PMC6897951 DOI: 10.1038/s41598-019-55092-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 11/19/2019] [Indexed: 11/23/2022] Open
Abstract
Membrane integral ATP synthases produce adenosine triphosphate, the universal “energy currency” of most organisms. However, important details of proton driven energy conversion are still unknown. We present the first high-resolution structure (2.3 Å) of the in meso crystallized c-ring of 14 subunits from spinach chloroplasts. The structure reveals molecular mechanisms of intersubunit contacts in the c14-ring, and it shows additional electron densities inside the c-ring which form circles parallel to the membrane plane. Similar densities were found in all known high-resolution structures of c-rings of F1FO ATP synthases from archaea and bacteria to eukaryotes. The densities might originate from isoprenoid quinones (such as coenzyme Q in mitochondria and plastoquinone in chloroplasts) that is consistent with differential UV-Vis spectroscopy of the c-ring samples, unusually large distance between polar/apolar interfaces inside the c-ring and universality among different species. Although additional experiments are required to verify this hypothesis, coenzyme Q and its analogues known as electron carriers of bioenergetic chains may be universal cofactors of ATP synthases, stabilizing c-ring and prevent ion leakage through it.
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13
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Imai Y, Inoshita T, Meng H, Shiba-Fukushima K, Hara KY, Sawamura N, Hattori N. Light-driven activation of mitochondrial proton-motive force improves motor behaviors in a Drosophila model of Parkinson's disease. Commun Biol 2019; 2:424. [PMID: 31799427 PMCID: PMC6874642 DOI: 10.1038/s42003-019-0674-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 11/01/2019] [Indexed: 02/06/2023] Open
Abstract
Mitochondrial degeneration is considered one of the major causes of Parkinson's disease (PD). Improved mitochondrial functions are expected to be a promising therapeutic strategy for PD. In this study, we introduced a light-driven proton transporter, Delta-rhodopsin (dR), to Drosophila mitochondria, where the mitochondrial proton-motive force (Δp) and mitochondrial membrane potential are maintained in a light-dependent manner. The loss of the PD-associated mitochondrial gene CHCHD2 resulted in reduced ATP production, enhanced mitochondrial peroxide production and lower Ca2+-buffering activity in dopaminergic (DA) terminals in flies. These cellular defects were improved by the light-dependent activation of mitochondrion-targeted dR (mito-dR). Moreover, mito-dR reversed the pathology caused by the CHCHD2 deficiency to suppress α-synuclein aggregation, DA neuronal loss, and elevated lipid peroxidation in brain tissue, improving motor behaviors. This study suggests the enhancement of Δp by mito-dR as a therapeutic mechanism that ameliorates neurodegeneration by protecting mitochondrial functions.
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Affiliation(s)
- Yuzuru Imai
- Department of Research for Parkinson’s Disease, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
| | - Tsuyoshi Inoshita
- Department of Treatment and Research in Multiple Sclerosis and Neuro-intractable Disease, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
| | - Hongrui Meng
- Department of Neurodegenerative and Demented Disorders, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
| | - Kahori Shiba-Fukushima
- Department of Treatment and Research in Multiple Sclerosis and Neuro-intractable Disease, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
| | - Kiyotaka Y. Hara
- Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, 422-8526 Japan
| | - Naoya Sawamura
- Research Organization for Nano & Life Innovation, Waseda University, Tokyo, 162-8480 Japan
- Faculty of Science and Engineering, Waseda University, Tokyo, 162-8480 Japan
| | - Nobutaka Hattori
- Department of Research for Parkinson’s Disease, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
- Department of Treatment and Research in Multiple Sclerosis and Neuro-intractable Disease, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
- Department of Neurodegenerative and Demented Disorders, Juntendo University Graduate School of Medicine, Tokyo, 113-8421 Japan
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14
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Wickstrand C, Nogly P, Nango E, Iwata S, Standfuss J, Neutze R. Bacteriorhodopsin: Structural Insights Revealed Using X-Ray Lasers and Synchrotron Radiation. Annu Rev Biochem 2019; 88:59-83. [DOI: 10.1146/annurev-biochem-013118-111327] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Directional transport of protons across an energy transducing membrane—proton pumping—is ubiquitous in biology. Bacteriorhodopsin (bR) is a light-driven proton pump that is activated by a buried all- trans retinal chromophore being photoisomerized to a 13- cis conformation. The mechanism by which photoisomerization initiates directional proton transport against a proton concentration gradient has been studied by a myriad of biochemical, biophysical, and structural techniques. X-ray free electron lasers (XFELs) have created new opportunities to probe the structural dynamics of bR at room temperature on timescales from femtoseconds to milliseconds using time-resolved serial femtosecond crystallography (TR-SFX). Wereview these recent developments and highlight where XFEL studies reveal new details concerning the structural mechanism of retinal photoisomerization and proton pumping. We also discuss the extent to which these insights were anticipated by earlier intermediate trapping studies using synchrotron radiation. TR-SFX will open up the field for dynamical studies of other proteins that are not naturally light-sensitive.
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Affiliation(s)
- Cecilia Wickstrand
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-40530 Gothenburg, Sweden
| | - Przemyslaw Nogly
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Eriko Nango
- RIKEN SPring-8 Center, Hyogo 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - So Iwata
- RIKEN SPring-8 Center, Hyogo 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Jörg Standfuss
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Richard Neutze
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-40530 Gothenburg, Sweden
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15
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Naito A, Makino Y, Shigeta A, Kawamura I. Photoreaction pathways and photointermediates of retinal-binding photoreceptor proteins as revealed by in situ photoirradiation solid-state NMR spectroscopy. Biophys Rev 2019; 11:167-181. [PMID: 30811009 DOI: 10.1007/s12551-019-00501-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 01/28/2019] [Indexed: 12/20/2022] Open
Abstract
Photoirradiation solid-state NMR spectroscopy is a powerful means to study photoreceptor retinal-binding proteins by the detection of short-lived photointermediates to elucidate the photoreaction cycle and photoactivated structural changes. An in situ photoirradiation solid-state NMR apparatus has been developed for the irradiation of samples with extremely high efficiency to enable observation of photointermediates which are stationary trapped states. Such observation enables elucidation of the photoreaction processes of photoreceptor membrane proteins. Therefore, in situ photoirradiation is particularly useful study the photocycle of retinal-binding proteins such as sensory rhodopsin I (SRI) and sensory rhodopsin II (SRII) because functional photointermediates have relatively longer half-lives than other photointermediates. As a result, several photointermediates have been trapped as stationary state and their detailed structures and photoreaction cycles have been revealed using photoirradiation solid-state NMR spectroscopy at low temperature. Photoreaction intermediates of bacteriorhodopsin, which functions to provide light-driven proton pump activity, were difficult to trap because the half-lives of the photointermediates were shorter than those of sensory rhodopsin. Therefore, these photointermediates are trapped in a freeze-trapped state at a very low temperature and the NMR signals were observed using a combination of photoirradiation and dynamic nuclear polarization (DNP) experiments.
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Affiliation(s)
- Akira Naito
- Graduate School of Engineering, Yokohama National University, Yokohama, 240-8501, Japan.
| | - Yoshiteru Makino
- Graduate School of Engineering, Yokohama National University, Yokohama, 240-8501, Japan
| | - Arisu Shigeta
- Graduate School of Engineering, Yokohama National University, Yokohama, 240-8501, Japan
| | - Izuru Kawamura
- Graduate School of Engineering, Yokohama National University, Yokohama, 240-8501, Japan
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16
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Cheng C, Kamiya M, Takemoto M, Ishitani R, Nureki O, Yoshida N, Hayashi S. An Atomistic Model of a Precursor State of Light-Induced Channel Opening of Channelrhodopsin. Biophys J 2018; 115:1281-1291. [PMID: 30236783 PMCID: PMC6170652 DOI: 10.1016/j.bpj.2018.08.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/11/2018] [Accepted: 08/13/2018] [Indexed: 01/01/2023] Open
Abstract
Channelrhodopsins (ChRs) are microbial light-gated ion channels with a retinal chromophore and are widely utilized in optogenetics to precisely control neuronal activity with light. Despite increasing understanding of their structures and photoactivation kinetics, the atomistic mechanism of light gating and ion conduction remains elusive. Here, we present an atomic structural model of a chimeric ChR in a precursor state of the channel opening determined by an accurate hybrid molecular simulation technique and a statistical theory of internal water distribution. The photoactivated structure features extensive tilt of the chromophore accompanied by redistribution of water molecules in its binding pocket, which is absent in previously known photoactivated structures of analogous photoreceptors, and widely agrees with structural and spectroscopic experimental evidence of ChRs. The atomistic model manifests a photoactivated ion-conduction pathway that is markedly different from a previously proposed one and successfully explains experimentally observed mutagenic effects on key channel properties.
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Affiliation(s)
- Cheng Cheng
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Motoshi Kamiya
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Mizuki Takemoto
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Ryuichiro Ishitani
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Osamu Nureki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Norio Yoshida
- Department of Chemistry, Graduate School of Science, Kyushu University, Fukuoka, Japan.
| | - Shigehiko Hayashi
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan.
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17
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Ding X, Sun C, Cui H, Chen S, Gao Y, Yang Y, Wang J, He X, Iuga D, Tian F, Watts A, Zhao X. Functional roles of tyrosine 185 during the bacteriorhodopsin photocycle as revealed by in situ spectroscopic studies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:1006-1014. [PMID: 29800547 DOI: 10.1016/j.bbabio.2018.05.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 04/15/2018] [Accepted: 05/20/2018] [Indexed: 01/22/2023]
Abstract
Tyrosine 185 (Y185), one of the aromatic residues within the retinal (Ret) chromophore binding pocket in helix F of bacteriorhodopsin (bR), is highly conserved among the microbial rhodopsin family proteins. Many studies have investigated the functions of Y185, but its underlying mechanism during the bR photocycle remains unclear. To address this research gap, in situ two-dimensional (2D) magic-angle spinning (MAS) solid-state NMR (ssNMR) of specifically labelled bR, combined with light-induced transient absorption change measurements, dynamic light scattering (DLS) measurements, titration analysis and site-directed mutagenesis, was used to elucidate the functional roles of Y185 during the bR photocycle in the native membrane environment. Different interaction modes were identified between Y185 and the Ret chromophore in the dark-adapted (inactive) state and M (active) state, indicating that Y185 may serve as a rotamer switch maintaining the protein dynamics, and plays an important role in the efficient proton-pumping mechanism in the bR purple membrane.
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Affiliation(s)
- Xiaoyan Ding
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China; Department of Biochemistry and Molecular Biology, Penn State College of Medicine, PA 17033-0850, USA
| | - Chao Sun
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Haolin Cui
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Sijin Chen
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Yujiao Gao
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Yanan Yang
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Juan Wang
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China
| | - Xiao He
- Shang Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, PR China
| | - Dinu Iuga
- The UK 850 MHz Solid-State NMR Facility, Department of Physics, University of Warwick, Coventry CV4 7AL, UK
| | - Fang Tian
- Department of Biochemistry and Molecular Biology, Penn State College of Medicine, PA 17033-0850, USA.
| | - Anthony Watts
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
| | - Xin Zhao
- Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Materials Science, East China Normal University, Shanghai 200062, PR China.
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18
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Tamogami J, Kikukawa T, Ohkawa K, Ohsawa N, Nara T, Demura M, Miyauchi S, Kimura-Someya T, Shirouzu M, Yokoyama S, Shimono K, Kamo N. Interhelical interactions between D92 and C218 in the cytoplasmic domain regulate proton uptake upon N-decay in the proton transport of Acetabularia rhodopsin II. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 183:35-45. [PMID: 29684719 DOI: 10.1016/j.jphotobiol.2018.04.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/07/2018] [Accepted: 04/07/2018] [Indexed: 01/01/2023]
Abstract
Acetabularia rhodopsin II (ARII or Ace2), an outward light-driven algal proton pump found in the giant unicellular marine alga Acetabularia acetabulum, has a unique property in the cytoplasmic (CP) side of its channel. The X-ray crystal structure of ARII in a dark state suggested the formation of an interhelical hydrogen bond between C218ARII and D92ARII, an internal proton donor to the Schiff base (Wada et al., 2011). In this report, we investigated the photocycles of two mutants at position C218ARII: C218AARII which disrupts the interaction with D92ARII, and C218SARII which potentially forms a stronger hydrogen bond. Both mutants exhibited slower photocycles compared to the wild-type pump. Together with several kinetic changes of the photoproducts in the first half of the photocycle, these replacements led to specific retardation of the N-to-O transition in the second half of the photocycle. In addition, measurements of the flash-induced proton uptake and release using a pH-sensitive indium-tin oxide electrode revealed a concomitant delay in the proton uptake. These observations strongly suggest the importance of a native weak hydrogen bond between C218ARII and D92ARII for proper proton translocation in the CP channel during N-decay. A putative role for the D92ARII-C218ARII interhelical hydrogen bond in the function of ARII is discussed.
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Affiliation(s)
- Jun Tamogami
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan.
| | - Takashi Kikukawa
- Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan; Global Station for Soft Matter, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo 001-0021, Japan
| | - Keisuke Ohkawa
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan
| | - Noboru Ohsawa
- RIKEN Systems and Structural Biology Center, Yokohama 230-0045, Japan; RIKEN Center for Life Science Technologies, Yokohama 230-0045, Japan
| | - Toshifumi Nara
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan
| | - Makoto Demura
- Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan; Global Station for Soft Matter, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo 001-0021, Japan
| | - Seiji Miyauchi
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan; Graduate School of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Tomomi Kimura-Someya
- RIKEN Systems and Structural Biology Center, Yokohama 230-0045, Japan; RIKEN Center for Life Science Technologies, Yokohama 230-0045, Japan
| | - Mikako Shirouzu
- RIKEN Systems and Structural Biology Center, Yokohama 230-0045, Japan; RIKEN Center for Life Science Technologies, Yokohama 230-0045, Japan
| | - Shigeyuki Yokoyama
- RIKEN Systems and Structural Biology Center, Yokohama 230-0045, Japan; RIKEN Structural Biology Laboratory, Yokohama 230-0045, Japan
| | - Kazumi Shimono
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan; Graduate School of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Naoki Kamo
- College of Pharmaceutical Sciences, Matsuyama University, Matsuyama, Ehime 790-8578, Japan; Faculty of Advanced Life Science, Hokkaido University, Sapporo 060-0810, Japan
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19
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Gozem S, Luk HL, Schapiro I, Olivucci M. Theory and Simulation of the Ultrafast Double-Bond Isomerization of Biological Chromophores. Chem Rev 2017; 117:13502-13565. [DOI: 10.1021/acs.chemrev.7b00177] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Samer Gozem
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30302, United States
| | - Hoi Ling Luk
- Chemistry
Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, United States
| | - Igor Schapiro
- Fritz
Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Massimo Olivucci
- Chemistry
Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, United States
- Dipartimento
di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro
2, 53100 Siena, Italy
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20
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Nango E, Royant A, Kubo M, Nakane T, Wickstrand C, Kimura T, Tanaka T, Tono K, Song C, Tanaka R, Arima T, Yamashita A, Kobayashi J, Hosaka T, Mizohata E, Nogly P, Sugahara M, Nam D, Nomura T, Shimamura T, Im D, Fujiwara T, Yamanaka Y, Jeon B, Nishizawa T, Oda K, Fukuda M, Andersson R, Båth P, Dods R, Davidsson J, Matsuoka S, Kawatake S, Murata M, Nureki O, Owada S, Kameshima T, Hatsui T, Joti Y, Schertler G, Yabashi M, Bondar AN, Standfuss J, Neutze R, Iwata S. A three-dimensional movie of structural changes in bacteriorhodopsin. Science 2016; 354:1552-1557. [DOI: 10.1126/science.aah3497] [Citation(s) in RCA: 294] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 11/21/2016] [Indexed: 01/24/2023]
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21
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Electrogenic steps of light-driven proton transport in ESR, a retinal protein from Exiguobacterium sibiricum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1741-1750. [DOI: 10.1016/j.bbabio.2016.08.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 08/06/2016] [Accepted: 08/11/2016] [Indexed: 02/01/2023]
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22
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Abe-Yoshizumi R, Inoue K, Kato HE, Nureki O, Kandori H. Role of Asn112 in a Light-Driven Sodium Ion-Pumping Rhodopsin. Biochemistry 2016; 55:5790-5797. [DOI: 10.1021/acs.biochem.6b00741] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rei Abe-Yoshizumi
- Department
of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
| | - Keiichi Inoue
- Department
of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology
Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- Frontier
Research Institute for Material Science, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Hideaki E. Kato
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Osamu Nureki
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hideki Kandori
- Department
of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- OptoBioTechnology
Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
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23
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Berbasova T, Santos EM, Nosrati M, Vasileiou C, Geiger JH, Borhan B. Light-Activated Reversible Imine Isomerization: Towards a Photochromic Protein Switch. Chembiochem 2016; 17:407-14. [PMID: 26684483 PMCID: PMC4835339 DOI: 10.1002/cbic.201500613] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Indexed: 01/07/2023]
Abstract
Mutants of cellular retinoic acid-binding protein II (CRABPII), engineered to bind all-trans-retinal as an iminium species, demonstrate photochromism upon irradiation with light at different wavelengths. UV light irradiation populates the cis-imine geometry, which has a high pKa , leading to protonation of the imine and subsequent "turn-on" of color. Yellow light irradiation yields the trans-imine isomer, which has a depressed pKa , leading to loss of color because the imine is not protonated. The protein-bound retinylidene chromophore undergoes photoinduced reversible interconversion between the colored and uncolored species, with excellent fatigue resistance.
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Affiliation(s)
- Tetyana Berbasova
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Elizabeth M Santos
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Meisam Nosrati
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Chrysoula Vasileiou
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - James H Geiger
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Babak Borhan
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
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24
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Conversion of a light-driven proton pump into a light-gated ion channel. Sci Rep 2015; 5:16450. [PMID: 26597707 PMCID: PMC4657025 DOI: 10.1038/srep16450] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 10/14/2015] [Indexed: 12/19/2022] Open
Abstract
Interest in microbial rhodopsins with ion pumping activity has been revitalized in the context of optogenetics, where light-driven ion pumps are used for cell hyperpolarization and voltage sensing. We identified an opsin-encoding gene (CsR) in the genome of the arctic alga Coccomyxa subellipsoidea C-169 that can produce large photocurrents in Xenopus oocytes. We used this property to analyze the function of individual residues in proton pumping. Modification of the highly conserved proton shuttling residue R83 or its interaction partner Y57 strongly reduced pumping power. Moreover, this mutation converted CsR at moderate electrochemical load into an operational proton channel with inward or outward rectification depending on the amino acid substitution. Together with molecular dynamics simulations, these data demonstrate that CsR-R83 and its interacting partner Y57 in conjunction with water molecules forms a proton shuttle that blocks passive proton flux during the dark-state but promotes proton movement uphill upon illumination.
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25
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Abstract
Rhodopsins are light-sensing proteins used in optogenetics. The word "rhodopsin" originates from the Greek words "rhodo" and "opsis," indicating rose and sight, respectively. Although the classical meaning of rhodopsin is the red-colored pigment in our eyes, the modern meaning of rhodopsin encompasses photoactive proteins containing a retinal chromophore in animals and microbes. Animal and microbial rhodopsins possess 11-cis and all-trans retinal, respectively, to capture light in seven transmembrane α-helices, and photoisomerizations into all-trans and 13-cis forms, respectively, initiate each function. Ion-transporting proteins can be found in microbial rhodopsins, such as light-gated channels and light-driven pumps, which are the main tools in optogenetics. Light-driven pumps, such as archaeal H(+) pump bacteriorhodopsin (BR) and Cl(-) pump halorhodopsin (HR), were discovered in the 1970s, and their mechanism has been extensively studied. On the other hand, different kinds of H(+) and Cl(-) pumps have been found in marine bacteria, such as proteorhodopsin (PR) and Fulvimarina pelagi rhodopsin (FR), respectively. In addition, a light-driven Na(+) pump was found, Krokinobacter eikastus rhodopsin 2 (KR2). These light-driven ion-pumping microbial rhodopsins are classified as DTD, TSA, DTE, NTQ, and NDQ rhodopsins for BR, HR, PR, FR, and KR2, respectively. Recent understanding of ion-pumping microbial rhodopsins is reviewed in this paper.
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Affiliation(s)
- Hideki Kandori
- Department of Frontier Materials and OptoBioTechnology Research Center, Nagoya Institute of Technology Nagoya, Japan
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26
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Wolf S, Freier E, Cui Q, Gerwert K. Infrared spectral marker bands characterizing a transient water wire inside a hydrophobic membrane protein. J Chem Phys 2015; 141:22D524. [PMID: 25494795 DOI: 10.1063/1.4902237] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Proton conduction along protein-bound "water wires" is an essential feature in membrane proteins. Here, we analyze in detail a transient water wire, which conducts protons via a hydrophobic barrier within a membrane protein to create a proton gradient. It is formed only for a millisecond out of three water molecules distributed at inactive positions in a polar environment in the ground state. The movement into a hydrophobic environment causes characteristic shifts of the water bands reflecting their different chemical properties. These band shifts are identified by time-resolved Fourier Transform Infrared difference spectroscopy and analyzed by biomolecular Quantum Mechanical/Molecular Mechanical simulations. A non-hydrogen bonded ("dangling") O-H stretching vibration band and a broad continuum absorbance caused by a combined vibration along the water wire are identified as characteristic marker bands of such water wires in a hydrophobic environment. The results provide a basic understanding of water wires in hydrophobic environments.
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Affiliation(s)
- Steffen Wolf
- Department of Biophysics, Ruhr-University Bochum, Universitätsstraße 150, 44780 Bochum, Germany
| | - Erik Freier
- Department of Biophysics, Chinese Academy of Sciences, Max-Planck-Gesellschaft Partner Institute for Computational Biology, 320 Yue Yang Road, 200031 Shanghai, China
| | - Qiang Cui
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin, Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
| | - Klaus Gerwert
- Department of Biophysics, Ruhr-University Bochum, Universitätsstraße 150, 44780 Bochum, Germany
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27
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Oshima K, Shigeta A, Makino Y, Kawamura I, Okitsu T, Wada A, Tuzi S, Iwasa T, Naito A. Characterization of photo-intermediates in the photo-reaction pathways of a bacteriorhodopsin Y185F mutant using in situ photo-irradiation solid-state NMR spectroscopy. Photochem Photobiol Sci 2015; 14:1694-702. [PMID: 26169449 DOI: 10.1039/c5pp00154d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photo-reaction pathways of a bacteriorhodopsin Y185F mutant were examined using in situ photo-irradiation solid-state NMR spectroscopy. (13)C CP MAS NMR spectra were recorded at -40 °C in the dark (D1), under irradiation with 520 nm light (L1), subsequently in the dark (D2), and again under irradiation with 520 nm light (L2). In the process from D1 to L1, the 13-cis, 15-syn (CS; bR548) state changed to a CS*- (13-cis, 15-syn) intermediate, which was highly stable at -40 °C, and the all-trans (AT; bR568) state transformed to an N-intermediate. Under the D2 conditions, the N-intermediate transformed to an O-intermediate, which was highly stable at -40 °C in the dark. During subsequent irradiation with 520 nm light (L2), the O-intermediate transformed to the N-intermediate through the AT state, whereas the CS*-intermediate did not change. The CS*-intermediate was converted to the AT state (or O-intermediate) after the temperature was increased to -20 °C. Upon subsequent increase of the temperature to 20 °C, the AT state (or O-intermediate) was converted to the CS state until reaching equilibrium. In this experiment, the chemical shift values of [20-(13)C, 14-(13)C]retinal provided the 13C[double bond, length as m-dash]C and 15C[double bond, length as m-dash]N configurations, respectively. From these data, the configurations of the AT and CS states and the CS*-, N-, and O-intermediates were determined to be (13-trans, 15-anti), (13-cis, 15-syn), (13-cis, 15-syn), (13-cis, 15-anti), and (13-trans, 15-anti), respectively. (13)C NMR signals of the CS*- and O-intermediates were observed for the first time for the Y185F bR mutant by in situ photo-irradiation solid-state NMR spectroscopy and the configuration of the CS*-intermediate was revealed to be significantly twisted from that of the CS state although both were assigned as (13-cis, 15-syn) configurations.
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Affiliation(s)
- Kyosuke Oshima
- Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
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Petrovskaya LE, Balashov SP, Lukashev EP, Imasheva ES, Gushchin IY, Dioumaev AK, Rubin AB, Dolgikh DA, Gordeliy VI, Lanyi JK, Kirpichnikov MP. ESR — A retinal protein with unusual properties from Exiguobacterium sibiricum. BIOCHEMISTRY (MOSCOW) 2015; 80:688-700. [DOI: 10.1134/s000629791506005x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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29
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Ogren JI, Yi A, Mamaev S, Li H, Spudich JL, Rothschild KJ. Proton transfers in a channelrhodopsin-1 studied by Fourier transform infrared (FTIR) difference spectroscopy and site-directed mutagenesis. J Biol Chem 2015; 290:12719-30. [PMID: 25802337 DOI: 10.1074/jbc.m114.634840] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Indexed: 11/06/2022] Open
Abstract
Channelrhodopsin-1 from the alga Chlamydomonas augustae (CaChR1) is a low-efficiency light-activated cation channel that exhibits properties useful for optogenetic applications such as a slow light inactivation and a red-shifted visible absorption maximum as compared with the more extensively studied channelrhodopsin-2 from Chlamydomonas reinhardtii (CrChR2). Previously, both resonance Raman and low-temperature FTIR difference spectroscopy revealed that unlike CrChR2, CaChR1 under our conditions exhibits an almost pure all-trans retinal composition in the unphotolyzed ground state and undergoes an all-trans to 13-cis isomerization during the primary phototransition typical of other microbial rhodopsins such as bacteriorhodopsin (BR). Here, we apply static and rapid-scan FTIR difference spectroscopy along with site-directed mutagenesis to characterize the proton transfer events occurring upon the formation of the long-lived conducting P2 (380) state of CaChR1. Assignment of carboxylic C=O stretch bands indicates that Asp-299 (homolog to Asp-212 in BR) becomes protonated and Asp-169 (homolog to Asp-85 in BR) undergoes a net change in hydrogen bonding relative to the unphotolyzed ground state of CaChR1. These data along with earlier FTIR measurements on the CaChR1 → P1 transition are consistent with a two-step proton relay mechanism that transfers a proton from Glu-169 to Asp-299 during the primary phototransition and from the Schiff base to Glu-169 during P2 (380) formation. The unusual charge neutrality of both Schiff base counterions in the P2 (380) conducting state suggests that these residues may function as part of a cation selective filter in the open channel state of CaChR1 as well as other low-efficiency ChRs.
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Affiliation(s)
- John I Ogren
- From the Molecular Biophysics Laboratory, Photonics Center and Department of Physics, Boston University, Boston, Massachusetts 02215 and
| | - Adrian Yi
- From the Molecular Biophysics Laboratory, Photonics Center and Department of Physics, Boston University, Boston, Massachusetts 02215 and
| | - Sergey Mamaev
- From the Molecular Biophysics Laboratory, Photonics Center and Department of Physics, Boston University, Boston, Massachusetts 02215 and
| | - Hai Li
- the Center for Membrane Biology, Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center, Houston, Texas 77030
| | - John L Spudich
- the Center for Membrane Biology, Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center, Houston, Texas 77030
| | - Kenneth J Rothschild
- From the Molecular Biophysics Laboratory, Photonics Center and Department of Physics, Boston University, Boston, Massachusetts 02215 and
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30
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Dynamic regulation of lipid-protein interactions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1849-59. [PMID: 25666872 DOI: 10.1016/j.bbamem.2015.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/27/2015] [Accepted: 01/29/2015] [Indexed: 02/07/2023]
Abstract
We review the importance of helix motions for the function of several important categories of membrane proteins and for the properties of several model molecular systems. For voltage-gated potassium or sodium channels, sliding, tilting and/or rotational movements of the S4 helix accompanied by a swapping of cognate side-chain ion-pair interactions regulate the channel gating. In the seven-helix G protein-coupled receptors, exemplified by the rhodopsins, collective helix motions serve to activate the functional signaling. Peptides which initially associate with lipid-bilayer membrane surfaces may undergo dynamic transitions from surface-bound to tilted-transmembrane orientations, sometimes accompanied by changes in the molecularity, formation of a pore or, more generally, the activation of biological function. For single-span membrane proteins, such as the tyrosine kinases, an interplay between juxtamembrane and transmembrane domains is likely to be crucial for the regulation of dimer assembly that in turn is associated with the functional responses to external signals. Additionally, we note that experiments with designed single-span transmembrane helices offer fundamental insights into the molecular features that govern protein-lipid interactions. This article is part of a Special Issue entitled: Lipid-protein interactions.
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31
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Wickstrand C, Dods R, Royant A, Neutze R. Bacteriorhodopsin: Would the real structural intermediates please stand up? Biochim Biophys Acta Gen Subj 2014; 1850:536-53. [PMID: 24918316 DOI: 10.1016/j.bbagen.2014.05.021] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/23/2014] [Accepted: 05/29/2014] [Indexed: 11/18/2022]
Abstract
BACKGROUND Bacteriorhodopsin (bR) is the simplest known light driven proton pump and has been heavily studied using structural methods: eighty four X-ray diffraction, six electron diffraction and three NMR structures of bR are deposited within the protein data bank. Twenty one X-ray structures report light induced structural changes and changes induced by mutation, changes in pH, thermal annealing or X-ray induced photo-reduction have also been examined. SCOPE OF REVIEW We argue that light-induced structural changes that are replicated across several studies by independent research groups are those most likely to represent what is happening in reality. We present both internal distance matrix analyses that sort deposited bR structures into hierarchal trees, and difference Fourier analysis of deposited X-ray diffraction data. MAJOR CONCLUSIONS An internal distance matrix analysis separates most wild-type bR structures according to their different crystal forms, indicating how the protein's structure is influenced by crystallization conditions. A similar analysis clusters eleven studies of illuminated bR crystals as one branch of a hierarchal tree with reproducible movements of the extracellular portion of helix C towards helix G, and of the cytoplasmic portion of helix F away from helices A, B and G. All crystallographic data deposited for illuminated crystals show negative difference density on a water molecule (Wat402) that forms H-bonds to the retinal Schiff Base and two aspartate residues (Asp85, Asp212) in the bR resting state. Other recurring difference density features indicated reproducible side-chain, backbone and water molecule displacements. X-ray induced radiation damage also disorders Wat402 but acts via cleaving the head-groups of Asp85 and Asp212. GENERAL SIGNIFICANCE A remarkable level of agreement exists when deposited structures and crystallographic observations are viewed as a whole. From this agreement a unified picture of the structural mechanism of light-induced proton pumping by bR emerges. This article is part of a Special Issue entitled Structural biochemistry and biophysics of membrane proteins.
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Affiliation(s)
- Cecilia Wickstrand
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-40530 Gothenburg, Sweden
| | - Robert Dods
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-40530 Gothenburg, Sweden
| | - Antoine Royant
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France; CNRS, IBS, F-38044 Grenoble, France; CEA, IBS, F-38044 Grenoble, France; European Synchrotron Radiation Facility, F-38043 Grenoble, France.
| | - Richard Neutze
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, SE-40530 Gothenburg, Sweden.
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Wang T, Oppawsky C, Duan Y, Tittor J, Oesterhelt D, Facciotti MT. Stable closure of the cytoplasmic half-channel is required for efficient proton transport at physiological membrane potentials in the bacteriorhodopsin catalytic cycle. Biochemistry 2014; 53:2380-90. [PMID: 24660845 PMCID: PMC4004217 DOI: 10.1021/bi4013808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The bacteriorhodopsin (BR) Asp96Gly/Phe171Cys/Phe219Leu
triple
mutant has been shown to translocate protons 66% as efficiently as
the wild-type protein. Light-dependent ATP synthesis in haloarchaeal
cells expressing the triple mutant is 85% that of the wild-type BR
expressing cells. Therefore, the functional activity of BR seems to
be largely preserved in the triple mutant despite the observations
that its ground-state structure resembles that of the wild-type M
state (i.e., the so-called cytoplasmically open state) and that the
mutant shows no significant structural changes during its photocycle,
in sharp contrast to what occurs in the wild-type protein in which
a large structural opening and closing occurs on the cytoplasmic side.
To resolve the contradiction between the apparent functional robustness
of the triple mutant and the presumed importance of the opening and
closing that occurs in the wild-type protein, we conducted additional
experiments to compare the behavior of wild-type and mutant proteins
under different operational loads. Specifically, we characterized
the ability of the two proteins to generate light-driven proton currents
against a range of membrane potentials. The wild-type protein showed
maximal conductance between −150 and −50 mV, whereas
the mutant showed maximal conductance at membrane potentials >+50
mV. Molecular dynamics (MD) simulations of the triple mutant were
also conducted to characterize structural changes in the protein and
in solvent accessibility that might help to functionally contextualize
the current–voltage data. These simulations revealed that the
cytoplasmic half-channel of the triple mutant is constitutively open
and dynamically exchanges water with the bulk. Collectively, the data
and simulations help to explain why this mutant BR does not mediate
photosynthetic growth of haloarchaeal cells, and they suggest that
the structural closing observed in the wild-type protein likely plays
a key role in minimizing substrate back flow in the face of electrochemical
driving forces present at physiological membrane potentials.
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Affiliation(s)
- Ting Wang
- Department of Biomedical Engineering and Genome Center, 451 East Health Science Drive, University of California , Davis, California 95616-8816, United States
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Ernst OP, Lodowski DT, Elstner M, Hegemann P, Brown L, Kandori H. Microbial and animal rhodopsins: structures, functions, and molecular mechanisms. Chem Rev 2014; 114:126-63. [PMID: 24364740 PMCID: PMC3979449 DOI: 10.1021/cr4003769] [Citation(s) in RCA: 759] [Impact Index Per Article: 75.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Oliver P. Ernst
- Departments
of Biochemistry and Molecular Genetics, University of Toronto, 1 King’s College Circle, Medical Sciences Building, Toronto, Ontario M5S 1A8, Canada
| | - David T. Lodowski
- Center
for Proteomics and Bioinformatics, Case
Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Marcus Elstner
- Institute
for Physical Chemistry, Karlsruhe Institute
of Technology, Kaiserstrasse
12, 76131 Karlsruhe, Germany
| | - Peter Hegemann
- Institute
of Biology, Experimental Biophysics, Humboldt-Universität
zu Berlin, Invalidenstrasse
42, 10115 Berlin, Germany
| | - Leonid
S. Brown
- Department
of Physics and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Hideki Kandori
- Department
of Frontier Materials, Nagoya Institute
of Technology, Showa-ku, Nagoya 466-8555, Japan
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34
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Rodríguez-Hernández F, Martínez-Mesa A, Uranga-Piña L. Hybrid quantum–classical study of the non-adiabatic cis–trans photoisomerization in a model polyatomic molecule. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2013.11.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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35
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Gerwert K, Freier E, Wolf S. The role of protein-bound water molecules in microbial rhodopsins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1837:606-13. [PMID: 24055285 DOI: 10.1016/j.bbabio.2013.09.006] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 09/08/2013] [Accepted: 09/10/2013] [Indexed: 02/06/2023]
Abstract
Protein-bound internal water molecules are essential features of the structure and function of microbial rhodopsins. Besides structural stabilization, they act as proton conductors and even proton storage sites. Currently, the most understood model system exhibiting such features is bacteriorhodopsin (bR). During the last 20 years, the importance of water molecules for proton transport has been revealed through this protein. It has been shown that water molecules are as essential as amino acids for proton transport and biological function. In this review, we present an overview of the historical development of this research on bR. We furthermore summarize the recently discovered protein-bound water features associated with proton transport. Specifically, we discuss a pentameric water/amino acid arrangement close to the protonated Schiff base as central proton-binding site, a protonated water cluster as proton storage site at the proton-release site, and a transient linear water chain at the proton uptake site. We highlight how protein conformational changes reposition or reorient internal water molecules, thereby guiding proton transport. Last, we compare the water positions in bR with those in other microbial rhodopsins to elucidate how protein-bound water molecules guide the function of microbial rhodopsins. This article is part of a Special Issue entitled: Retinal Proteins - You can teach an old dog new tricks.
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Affiliation(s)
- Klaus Gerwert
- Department of Biophysics, University of Bochum, ND 04 North, 44780 Bochum, Germany; Department of Biophysics, Chinese Academy of Sciences-Max-Planck Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences (SIBS), 320 Yue Yang Lu, 200031 Shanghai, PR China.
| | - Erik Freier
- Department of Biophysics, University of Bochum, ND 04 North, 44780 Bochum, Germany
| | - Steffen Wolf
- Department of Biophysics, Chinese Academy of Sciences-Max-Planck Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences (SIBS), 320 Yue Yang Lu, 200031 Shanghai, PR China
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36
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Wang T, Sessions AO, Lunde CS, Rouhani S, Glaeser RM, Duan Y, Facciotti MT. Deprotonation of D96 in bacteriorhodopsin opens the proton uptake pathway. Structure 2013; 21:290-7. [PMID: 23394942 DOI: 10.1016/j.str.2012.12.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2012] [Revised: 12/08/2012] [Accepted: 12/12/2012] [Indexed: 11/18/2022]
Abstract
Despite extensive investigation, the precise mechanism controlling the opening of the cytoplasmic proton uptake pathway in bacteriorhodopsin (bR) has remained a mystery. From an analysis of the X-ray structure of the D96G/F171C/F219L triple mutant of bR and 60 independent molecular dynamics simulations of bR photointermediates, we report that the deprotonation of D96, a key residue in proton transfer reactions, serves two roles that occur sequentially. First, D96 donates a proton to the Schiff base. Subsequently, the deprotonation of D96 serves to "unlatch" the cytoplasmic side. The latching function of D96 appears to be remarkably robust, functioning to open hydration channels in all photointermediate structures. These results suggest that the protonation state of D96 may be the critical biophysical cue controlling the opening and closing of the cytoplasmic half-channel in bR. We suspect that this protonation-switch mechanism could also be utilized in other proton pumps to minimize backflow and reinforce directionality.
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Affiliation(s)
- Ting Wang
- Genome Center and Department of Biomedical Engineering, University of California at Davis, One Shields Avenue, Davis, CA 95616, USA
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37
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Wang T, Facciotti MT, Duan Y. Schiff base switch II precedes the retinal thermal isomerization in the photocycle of bacteriorhodopsin. PLoS One 2013; 8:e69882. [PMID: 23922839 PMCID: PMC3726731 DOI: 10.1371/journal.pone.0069882] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 06/13/2013] [Indexed: 11/21/2022] Open
Abstract
In bacteriorhodopsin, the order of molecular events that control the cytoplasmic or extracellular accessibility of the Schiff bases (SB) are not well understood. We use molecular dynamics simulations to study a process involved in the second accessibility switch of SB that occurs after its reprotonation in the N intermediate of the photocycle. We find that once protonated, the SB C15 = NZ bond switches from a cytoplasmic facing (13-cis, 15-anti) configuration to an extracellular facing (13-cis, 15-syn) configuration on the pico to nanosecond timescale. Significantly, rotation about the retinal’s C13 = C14 double bond is not observed. The dynamics of the isomeric state transitions of the protonated SB are strongly influenced by the surrounding charges and dielectric effects of other buried ions, particularly D96 and D212. Our simulations indicate that the thermal isomerization of retinal from 13-cis back to all-trans likely occurs independently from and after the SB C15 = NZ rotation in the N-to-O transition.
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Affiliation(s)
- Ting Wang
- UC Davis Genome Center, University of California Davis, Davis, California, United States of America
- Department of Biomedical Engineering, University of California Davis, Davis, California, United States of America
| | - Marc T. Facciotti
- UC Davis Genome Center, University of California Davis, Davis, California, United States of America
- Department of Biomedical Engineering, University of California Davis, Davis, California, United States of America
- * E-mail: (MF); (YD)
| | - Yong Duan
- UC Davis Genome Center, University of California Davis, Davis, California, United States of America
- Department of Biomedical Engineering, University of California Davis, Davis, California, United States of America
- * E-mail: (MF); (YD)
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38
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Simón-Vázquez R, Domínguez M, Lórenz-Fonfría VA, Alvarez S, Bourdelande JL, de Lera AR, Padrós E, Perálvarez-Marín A. Probing a polar cluster in the retinal binding pocket of bacteriorhodopsin by a chemical design approach. PLoS One 2012; 7:e42447. [PMID: 22879987 PMCID: PMC3411786 DOI: 10.1371/journal.pone.0042447] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 07/06/2012] [Indexed: 11/24/2022] Open
Abstract
Bacteriorhodopsin has a polar cluster of amino acids surrounding the retinal molecule, which is responsible for light harvesting to fuel proton pumping. From our previous studies, we have shown that threonine 90 is the pivotal amino acid in this polar cluster, both functionally and structurally. In an attempt to perform a phenotype rescue, we have chemically designed a retinal analogue molecule to compensate the drastic effects of the T90A mutation in bacteriorhodopsin. This analogue substitutes the methyl group at position C13 of the retinal hydrocarbon chain by and ethyl group (20-methyl retinal). We have analyzed the effect of reconstituting the wild-type and the T90A mutant apoproteins with all-trans-retinal and its 20-methyl derivative (hereafter, 13-ethyl retinal). Biophysical characterization indicates that recovering the steric interaction between the residue 90 and retinal, eases the accommodation of the chromophore, however it is not enough for a complete phenotype rescue. The characterization of these chemically engineered chromoproteins provides further insight into the role of the hydrogen bond network and the steric interactions involving the retinal binding pocket in bacteriorhodopsin and other microbial sensory rhodopsins.
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Affiliation(s)
- Rosana Simón-Vázquez
- Departament de Bioquímica i de Biologia Molecular and Centre d'Estudis en Biofísica, Universitat Autònoma de Barcelona, Barcelona, Spain
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39
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Zhang J, Yamazaki Y, Hikake M, Murakami M, Ihara K, Kouyama T. Crystal structure of the O intermediate of the Leu93→Ala mutant of bacteriorhodopsin. Proteins 2012; 80:2384-96. [DOI: 10.1002/prot.24124] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 05/05/2012] [Accepted: 05/14/2012] [Indexed: 12/23/2022]
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40
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Fan Y, Solomon P, Oliver RP, Brown LS. Photochemical characterization of a novel fungal rhodopsin from Phaeosphaeria nodorum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1457-66. [PMID: 21791197 DOI: 10.1016/j.bbabio.2011.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 07/11/2011] [Accepted: 07/12/2011] [Indexed: 02/09/2023]
Abstract
Eukaryotic microbial rhodopsins are widespread bacteriorhodopsin-like proteins found in many lower eukaryotic groups including fungi. Many fungi contain multiple rhodopsins, some significantly diverged from the original bacteriorhodopsin template. Although few fungal rhodopsins have been studied biophysically, both fast-cycling light-driven proton pumps and slow-cycling photosensors have been found. The purpose of this study was to characterize photochemically a new subgroup of fungal rhodopsins, the so-called auxiliary group. The study used the two known rhodopsin genes from the fungal wheat pathogen, Phaeosphaeria nodorum. One of the genes is a member of the auxiliary group while the other is highly similar to previously characterized proton-pumping Leptosphaeria rhodopsin. Auxiliary rhodopsin genes from a range of species form a distinct group with a unique primary structure and are located in carotenoid biosynthesis gene cluster. Amino acid conservation pattern suggests that auxiliary rhodopsins retain the transmembrane core of bacteriorhodopsins, including all residues important for proton transport, but have unique polar intramembrane residues. Spectroscopic characterization of the two yeast-expressed Phaeosphaeria rhodopsins showed many similarities: absorption spectra, conformation of the retinal chromophore, fast photocycling, and carboxylic acid protonation changes. It is likely that both Phaeosphaeria rhodopsins are proton-pumping, at least in vitro. We suggest that auxiliary rhodopsins have separated from their ancestors fairly recently and have acquired the ability to interact with as yet unidentified transducers, performing a photosensory function without changing their spectral properties and basic photochemistry.
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Affiliation(s)
- Ying Fan
- Department of Physics and Biophysics Interdepartmental Group, University of Guelph, Ontario, Canada, N1G 2W1
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41
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Proton transfer via a transient linear water-molecule chain in a membrane protein. Proc Natl Acad Sci U S A 2011; 108:11435-9. [PMID: 21709261 DOI: 10.1073/pnas.1104735108] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
High-resolution protein ground-state structures of proton pumps and channels have revealed internal protein-bound water molecules. Their possible active involvement in protein function has recently come into focus. An illustration of the formation of a protonated protein-bound water cluster that is actively involved in proton transfer was described for the membrane protein bacteriorhodopsin (bR) [Garczarek F, Gerwert K (2006) Nature 439:109-112]. Here we show through a combination of time-resolved FTIR spectroscopy and molecular dynamics simulations that three protein-bound water molecules are rearranged by a protein conformational change that resulted in a transient Grotthuss-type proton-transfer chain extending through a hydrophobic protein region of bR. This transient linear water chain facilitates proton transfer at an intermediate conformation only, thereby directing proton transfer within the protein. The rearrangement of protein-bound water molecules that we describe, from inactive positions in the ground state to an active chain in an intermediate state, appears to be energetically favored relative to transient incorporation of water molecules from the bulk. Our discovery provides insight into proton-transfer mechanisms through hydrophobic core regions of ubiquitous membrane spanning proteins such as G-protein coupled receptors or cytochrome C oxidases.
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42
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Borshchevskiy VI, Round ES, Popov AN, Büldt G, Gordeliy VI. X-ray-radiation-induced changes in bacteriorhodopsin structure. J Mol Biol 2011; 409:813-25. [PMID: 21530535 DOI: 10.1016/j.jmb.2011.04.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 04/12/2011] [Accepted: 04/13/2011] [Indexed: 11/29/2022]
Abstract
Bacteriorhodopsin (bR) provides light-driven vectorial proton transport across a cell membrane. Creation of electrochemical potential at the membrane is a universal step in energy transformation in a cell. Published atomic crystallographic models of early intermediate states of bR show a significant difference between them, and conclusions about pumping mechanisms have been contradictory. Here, we present a quantitative high-resolution crystallographic study of conformational changes in bR induced by X-ray absorption. It is shown that X-ray doses that are usually accumulated during data collection for intermediate-state studies are sufficient to significantly alter the structure of the protein. X-ray-induced changes occur primarily in the active site of bR. Structural modeling showed that X-ray absorption triggers retinal isomerization accompanied by the disappearance of electron densities corresponding to the water molecule W402 bound to the Schiff base. It is demonstrated that these and other X-ray-induced changes may mimic functional conformational changes of bR leading to misinterpretation of the earlier obtained X-ray crystallographic structures of photointermediates.
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Affiliation(s)
- Valentin I Borshchevskiy
- Laboratoire des Protéines Membranaires, Institut de Biologie Structurale J.-P. Ebel, UMR5075 CEA-CNRS-UJF, Grenoble 38027, France
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Bondar AN, Fischer S, Smith JC. Water Pathways in the Bacteriorhodopsin Proton Pump. J Membr Biol 2010; 239:73-84. [DOI: 10.1007/s00232-010-9329-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 11/05/2010] [Indexed: 01/18/2023]
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Tehan BG, Lloyd EJ, Wong MG, Chalmers DK. Analysis of agonism by dopamine at the dopaminergic D 2 G-protein coupled receptor based on comparative modelling of rhodopsin. MOLECULAR SIMULATION 2010. [DOI: 10.1080/0892702021000002548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Irie M. Photochromism of diarylethene single molecules and single crystals. Photochem Photobiol Sci 2010; 9:1535-42. [PMID: 20959925 DOI: 10.1039/c0pp00251h] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photochromism is characterized as a reversible colour change of a chemical species upon photoirradiation. Although vast numbers of photochromic molecules have been so far synthesized, molecules which exhibit thermally irreversible photochromic reactivity are limited within a few families of compounds. Among the thermally irreversible photochromic molecules, diarylethene derivatives are the most promising candidates for applications to opto-electronic devices because of their fatigue resistance, high sensitivity and rapid response. In this review, characteristic photochromic performances of the derivatives, detection and analysis of the photochromic reactions at a single-molecule level and application of the single-crystalline photochromism to molecular machinery will be described.
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Affiliation(s)
- Masahiro Irie
- Department of Chemistry and Research Center for Smart Molecules, Rikkyo University, Nishi-Ikebukuro 3-34-1, Toshima-ku, Tokyo, 171-8501, Japan.
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Westenhoff S, Nazarenko E, Malmerberg E, Davidsson J, Katona G, Neutze R. Time-resolved structural studies of protein reaction dynamics: a smorgasbord of X-ray approaches. Acta Crystallogr A 2010; 66:207-19. [PMID: 20164644 PMCID: PMC2824530 DOI: 10.1107/s0108767309054361] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 12/16/2009] [Indexed: 11/26/2022] Open
Abstract
Time-resolved structural studies of proteins have undergone several significant developments during the last decade. Recent developments using time-resolved X-ray methods, such as time-resolved Laue diffraction, low-temperature intermediate trapping, time-resolved wide-angle X-ray scattering and time-resolved X-ray absorption spectroscopy, are reviewed. Proteins undergo conformational changes during their biological function. As such, a high-resolution structure of a protein’s resting conformation provides a starting point for elucidating its reaction mechanism, but provides no direct information concerning the protein’s conformational dynamics. Several X-ray methods have been developed to elucidate those conformational changes that occur during a protein’s reaction, including time-resolved Laue diffraction and intermediate trapping studies on three-dimensional protein crystals, and time-resolved wide-angle X-ray scattering and X-ray absorption studies on proteins in the solution phase. This review emphasizes the scope and limitations of these complementary experimental approaches when seeking to understand protein conformational dynamics. These methods are illustrated using a limited set of examples including myoglobin and haemoglobin in complex with carbon monoxide, the simple light-driven proton pump bacteriorhodopsin, and the superoxide scavenger superoxide reductase. In conclusion, likely future developments of these methods at synchrotron X-ray sources and the potential impact of emerging X-ray free-electron laser facilities are speculated upon.
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Affiliation(s)
- Sebastian Westenhoff
- Department of Chemistry, Biochemistry and Biophysics, University of Gothenburg, Box 462, SE-40530 Gothenburg, Sweden
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Saitô H, Kira A, Arakawa T, Tanio M, Tuzi S, Naito A. Suppressed or recovered intensities analysis in site-directed 13C NMR: Assessment of low-frequency fluctuations in bacteriorhodopsin and D85N mutants revisited. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:167-76. [DOI: 10.1016/j.bbamem.2009.06.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 06/08/2009] [Accepted: 06/30/2009] [Indexed: 11/16/2022]
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Andersson M, Malmerberg E, Westenhoff S, Katona G, Cammarata M, Wöhri AB, Johansson LC, Ewald F, Eklund M, Wulff M, Davidsson J, Neutze R. Structural Dynamics of Light-Driven Proton Pumps. Structure 2009; 17:1265-75. [DOI: 10.1016/j.str.2009.07.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Revised: 07/07/2009] [Accepted: 07/09/2009] [Indexed: 10/20/2022]
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Yamamoto M, Hayakawa N, Murakami M, Kouyama T. Crystal structures of different substrates of bacteriorhodopsin's M intermediate at various pH levels. J Mol Biol 2009; 393:559-73. [PMID: 19712684 DOI: 10.1016/j.jmb.2009.08.047] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 08/18/2009] [Accepted: 08/19/2009] [Indexed: 11/16/2022]
Abstract
The hexagonal P622 crystal of bacteriorhodopsin, which is made up of stacked membranes, is stable provided that the precipitant concentration in the soaking solution is higher than a critical value (i.e., 1.5 M ammonium sulfate). Diffraction data showed that the crystal lattice shrank linearly with increasing precipitant concentration, due primarily to narrowing of intermembrane spaces. Although the crystal shrinkage did not affect the rate of formation of the photoreaction M intermediate, its lifetime increased exponentially with the precipitant concentration. It was suggested that the energetic barrier of the M-to-N transition becomes higher when the motional freedom of the EF loop is reduced by crystal lattice force. As a result of this property, the M state accumulated predominantly when the crystal that was soaked at a high precipitant concentration was illuminated at room temperature. Structural data obtained at various pH levels showed that the overall structure of M is not strongly dependent on pH, except that Glu194 and Glu204 in the proton release complex are more separated at pH 7 than at pH 4.4. This result suggests that light-induced disruption of the paired structure of Glu194 and Glu204 is incomplete when external pH is lower than the pK(a) value of the proton release group in the M state.
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Affiliation(s)
- Masataka Yamamoto
- Department of Physics, Graduate School of Science, Nagoya University, Nagoya, Japan
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Hirai T, Subramaniam S, Lanyi JK. Structural snapshots of conformational changes in a seven-helix membrane protein: lessons from bacteriorhodopsin. Curr Opin Struct Biol 2009; 19:433-9. [PMID: 19643594 DOI: 10.1016/j.sbi.2009.07.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 07/09/2009] [Accepted: 07/10/2009] [Indexed: 11/28/2022]
Abstract
Recent advances in crystallizing integral membrane proteins have led to atomic models for the structures of several seven-helix membrane proteins, including those in the G-protein-coupled receptor family. Further steps toward exploring structure-function relationships will undoubtedly involve determination of the structural changes that occur during the various stages of receptor activation and deactivation. We expect that these efforts will bear many parallels to the studies of conformational changes in bacteriorhodopsin, which still remains the best-studied seven-helix membrane protein. Here, we provide a brief review of some of the lessons learned, the challenges faced, and the controversies over the last decade with determining conformational changes in bacteriorhodopsin. Our hope is that this analysis will be instructive for similar structural studies, especially of other seven-helix membrane proteins, in the coming decade.
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Affiliation(s)
- Teruhisa Hirai
- Three-dimensional Microscopy Research Team, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
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