1
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Nakasone Y, Murakami H, Tokonami S, Oda T, Terazima M. Time-resolved study on signaling pathway of photoactivated adenylate cyclase and its nonlinear optical response. J Biol Chem 2023; 299:105285. [PMID: 37742920 PMCID: PMC10634658 DOI: 10.1016/j.jbc.2023.105285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/06/2023] [Accepted: 09/18/2023] [Indexed: 09/26/2023] Open
Abstract
Photoactivated adenylate cyclases (PACs) are multidomain BLUF proteins that regulate the cellular levels of cAMP in a light-dependent manner. The signaling route and dynamics of PAC from Oscillatoria acuminata (OaPAC), which consists of a light sensor BLUF domain, an adenylate cyclase domain, and a connector helix (α3-helix), were studied by detecting conformational changes in the protein moiety. Although circular dichroism and small-angle X-ray scattering measurements did not show significant changes upon light illumination, the transient grating method successfully detected light-induced changes in the diffusion coefficient (diffusion-sensitive conformational change (DSCC)) of full-length OaPAC and the BLUF domain with the α3-helix. DSCC of full-length OaPAC was observed only when both protomers in a dimer were photoconverted. This light intensity dependence suggests that OaPAC is a cyclase with a nonlinear light intensity response. The enzymatic activity indeed nonlinearly depends on light intensity, that is, OaPAC is activated under strong light conditions. It was also found that both DSCC and enzymatic activity were suppressed by a mutation in the W90 residue, indicating the importance of the highly conserved Trp in many BLUF domains for the function. Based on these findings, a reaction scheme was proposed together with the reaction dynamics.
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Affiliation(s)
- Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Hiroto Murakami
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Shunrou Tokonami
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Takashi Oda
- Department of Life Science and Research Center for Life Science, College of Science, Rikkyo University, Tokyo, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan.
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2
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Tokonami S, Nakasone Y, Terazima M. Effects of N- and C-terminal regions on oligomeric formation of blue light sensor protein SyPixD. Protein Sci 2023; 32:e4658. [PMID: 37184370 PMCID: PMC10211260 DOI: 10.1002/pro.4658] [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: 04/06/2023] [Revised: 05/08/2023] [Accepted: 05/10/2023] [Indexed: 05/16/2023]
Abstract
A sensor of blue-light using flavin adenine dinucleotide (BLUF) is a typical blue light photoreceptor domain that is found in many photosensor proteins in bacteria and some eukaryotic algae. SyPixD in Synechocystis is one of the well-studied BLUF proteins. In the dark state, it forms a decamer and, upon photoexcitation, a dissociation reaction takes place to yield dimers. Such change in the intermolecular interactions of the protomers is important for the biological function. The effect of the N- and C-terminal sequences on the stability of SyPixD oligomeric states and photoreactions of SyPixD were studied to understand how the oligomeric form is maintained with weak interaction. It was found that a few residues that frequently persist at the N-terminus after removing a tag for purification are sensitive to the stability of the decamer structure. Even two or three residues at the N-terminus considerably reduces decamer stability, whereas four or more residues completely prevent decamer formation. Unexpectedly, truncating C-terminal sequences, which locate far from any protomer interface and of which structure is undetermined in crystal structure, also destabilizes the decamer structure. This destabilization is also apparent from the dissociation reaction dynamics detected by the transient grating and transient absorption measurements. The dissociation reaction is faster and the yield increases when the C-terminus does not contain seven amino acid residues. Photoexcitation induces a conformational change in the C-terminus of the decamer but not the dimer.
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Affiliation(s)
- Shunrou Tokonami
- Department of Chemistry, Graduate School of ScienceKyoto UniversityKyotoJapan
| | - Yusuke Nakasone
- Department of Chemistry, Graduate School of ScienceKyoto UniversityKyotoJapan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of ScienceKyoto UniversityKyotoJapan
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3
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Hontani Y, Mehlhorn J, Domratcheva T, Beck S, Kloz M, Hegemann P, Mathes T, Kennis JTM. Spectroscopic and Computational Observation of Glutamine Tautomerization in the Blue Light Sensing Using Flavin Domain Photoreaction. J Am Chem Soc 2023; 145:1040-1052. [PMID: 36607126 PMCID: PMC9853863 DOI: 10.1021/jacs.2c10621] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Blue light sensing using flavin (BLUF) domains constitute a family of flavin-binding photoreceptors of bacteria and eukaryotic algae. BLUF photoactivation proceeds via a light-driven hydrogen-bond switch among flavin adenine dinucleotide (FAD) and glutamine and tyrosine side chains, whereby FAD undergoes electron and proton transfer with tyrosine and is subsequently re-oxidized by a hydrogen back-shuttle in picoseconds, constituting an important model system to understand proton-coupled electron transfer in biology. The specific structure of the hydrogen-bond patterns and the prevalence of glutamine tautomeric states in dark-adapted (DA) and light-activated (LA) states have remained controversial. Here, we present a combined femtosecond stimulated Raman spectroscopy (FSRS), computational chemistry, and site-selective isotope labeling Fourier-transform infrared spectroscopy (FTIR) study of the Slr1694 BLUF domain. FSRS showed distinct vibrational bands from the FADS1 singlet excited state. We observed small but significant shifts in the excited-state vibrational frequency patterns of the DA and LA states, indicating that these frequencies constitute a sensitive probe for the hydrogen-bond arrangement around FAD. Excited-state model calculations utilizing four different realizations of hydrogen bond patterns and glutamine tautomeric states were consistent with a BLUF reaction model that involved glutamine tautomerization to imidic acid, accompanied by a rotation of its side chain. A combined FTIR and double-isotope labeling study, with 13C labeling of FAD and 15N labeling of glutamine, identified the glutamine imidic acid C═N stretch vibration in the LA state and the Gln C═O in the DA state. Hence, our study provides support for glutamine tautomerization and side-chain rotation in the BLUF photoreaction.
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Affiliation(s)
- Yusaku Hontani
- Department
of Physics and Astronomy, Vrije Universiteit
Amsterdam, 1081 HV Amsterdam, De Boelelaan, The Netherlands
| | - Jennifer Mehlhorn
- Institut
für Biologie, Experimentelle Biophysik, Humboldt Universität zu Berlin, Invalidenstrasse 42, D-10115 Berlin, Germany
| | - Tatiana Domratcheva
- Department
of Biomolecular Mechanisms, Max Planck Institute
for Medical Research, 69120 Heidelberg, Germany,Department
of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Sebastian Beck
- Department
of Chemistry, Humboldt-Universität
zu Berlin, Brook-Taylor-Str.
2, 12489 Berlin, Germany
| | - Miroslav Kloz
- Department
of Physics and Astronomy, Vrije Universiteit
Amsterdam, 1081 HV Amsterdam, De Boelelaan, The Netherlands,Institute
of Physics, ELI-Beamlines, Na Slovance 2, 182
21 Praha 8, Czech Republic
| | - Peter Hegemann
- Institut
für Biologie, Experimentelle Biophysik, Humboldt Universität zu Berlin, Invalidenstrasse 42, D-10115 Berlin, Germany
| | - Tilo Mathes
- Department
of Physics and Astronomy, Vrije Universiteit
Amsterdam, 1081 HV Amsterdam, De Boelelaan, The Netherlands,Institut
für Biologie, Experimentelle Biophysik, Humboldt Universität zu Berlin, Invalidenstrasse 42, D-10115 Berlin, Germany
| | - John T. M. Kennis
- Department
of Physics and Astronomy, Vrije Universiteit
Amsterdam, 1081 HV Amsterdam, De Boelelaan, The Netherlands,
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4
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Tokonami S, Onose M, Nakasone Y, Terazima M. Slow Conformational Changes of Blue Light Sensor BLUF Proteins in Milliseconds. J Am Chem Soc 2022; 144:4080-4090. [PMID: 35196858 DOI: 10.1021/jacs.1c13121] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Blue light sensor using flavin (BLUF) proteins consist of flavin-binding BLUF domains and functional domains. Upon blue light excitation, the hydrogen bond network around the flavin chromophore changes, and the absorption spectrum in the visible region exhibits a red shift. Ultimately, the light information received in the BLUF domain is transmitted to the functional region. It has been believed that this red shift is complete within nanoseconds. In this study, slow reaction kinetics were discovered in milliseconds (τ1- and τ2-phase) for all the BLUF proteins examined (AppA, OaPAC, BlrP1, YcgF, PapB, SyPixD, and TePixD). Despite extensive reports on BLUF, this is the first clear observation of the BLUF protein absorption change with the duration in the millisecond time region. From the measurements of some domain-deleted mutants of OaPAC and two chimeric mutants of PixD proteins, it was found that the slower dynamics (τ2-phase) are strongly affected by the size and nature of the C-terminal region adjacent to the BLUF domain. Hence, this millisecond reaction is a significant indicator of conformational changes in the C-terminal region, which is essential for the biological functions. On the other hand, the τ1-phase commonly exists in all BLUF proteins, including any mutants. The origin of the slow dynamics was studied using site-specific mutants. These results clearly show the importance of Trp in the BLUF domain. Based on this, a reaction scheme for the BLUF reaction is proposed.
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Affiliation(s)
- Shunrou Tokonami
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Morihiko Onose
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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5
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Shibata K, Nakasone Y, Terazima M. Selective Photoinduced Dimerization and Slow Recovery of a BLUF Domain of EB1. J Phys Chem B 2022; 126:1024-1033. [PMID: 35089048 DOI: 10.1021/acs.jpcb.1c10100] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The EAL-BLUF fragment from Magnetococcus marinus BldP1 (EB1) light-dependently hydrolyzes c-di-GMP. Herein, the photoreaction of the BLUF domain of EB1 (eBLUF) is studied. It is found for the first time that a monomeric BLUF domain forms a dimer upon illumination and its dark recovery is very slow. The dimer of light- and dark-state protomers (LD-dimer) is much more stable than that of two light-state protomers (LL-dimer), and the dark recovery of the LD-dimer is approximately 20 times slower than that of the LL-dimer, which is suitable for optogenetic tools. The secondary structure of the L-monomer is different from those of the D-monomer and the LD-dimer. The transient grating measurements reveal that this conformational change occurs simultaneously with dimerization. Although the W91A mutant exhibits a spectral red shift, it forms a heterodimer with the L-monomer of wild-type eBLUF with similar stability to the LD-dimer. This suggests that the conformation of the dimerization site of W91A is similar to that of the dark state (dark-mimic mutant); that is, the light-induced structural changes in the chromophore cavity are not transferred to the other part of the protein. The selective photoinduced dimerization of eBLUF is potentially useful to control interprotein interactions between two different effector domains bound to these proteins.
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Affiliation(s)
- Kosei Shibata
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yusuke Nakasone
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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6
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Kang X, Chen Z, Zhou Z, Zhou Y, Tang S, Zhang Y, Zhang T, Ding B, Zhong D. Direct Observation of Ultrafast Proton Rocking in the BLUF Domain. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiu‐Wen Kang
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Zijing Chen
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Zhongneng Zhou
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Yalin Zhou
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Siwei Tang
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Yifei Zhang
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Tianyi Zhang
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Bei Ding
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
| | - Dongping Zhong
- Center for Ultrafast Science and Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China
- Department of Physics Department of Chemistry and Biochemistry and Programs of Biophysics Chemical Physics, and Biochemistry The Ohio State University Columbus OH 43210 USA
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7
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Ding B, Kang XW, Chen Z, Zhou Z, Zhou Y, Tang S, Zhang Y, Zhang T, Zhong D. Direct Observation of Ultrafast Proton Rocking in the BLUF Domain. Angew Chem Int Ed Engl 2021; 61:e202114423. [PMID: 34927328 DOI: 10.1002/anie.202114423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Indexed: 11/10/2022]
Abstract
We present direct observation of ultrafast proton rocking in the central motif of a BLUF domain protein scaffold. The mutant design has taken considerations of modulating the proton-coupled electron transfer (PCET) driving forces by replacing Tyr in the original motif with Trp, as well as of removing the interference of a competing electron transfer pathway. Using femtosecond pump-probe spectroscopy and detailed kinetics analysis, we resolved an electron-transfer-coupled Grotthuss-type forward and reversed proton rocking along the FMN-Gln-Trp proton relay chain. The rates of forward and reversed proton transfer are determined to be very close, namely 51 ps vs 52 ps. The kinetic isotope effect (KIE) constants associated with the forward and reversed proton transfer are 3.9 and 5.3, respectively. The observation of ultrafast proton rocking is not only a crucial step towards revealing the nature of proton relay in BLUF domain, but also provides a new paradigm of proton transfer in proteins for theoretical investigations.
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Affiliation(s)
- Bei Ding
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, 800 Dongchuan Road, 200240, Shanghai, CHINA
| | - Xiu-Wen Kang
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Zijing Chen
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Zhongneng Zhou
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Yalin Zhou
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Siwei Tang
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Yifei Zhang
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Tianyi Zhang
- Shanghai Jiao Tong University, School of Chemistry and Chemical Engineering, CHINA
| | - Dongping Zhong
- The Ohio State University, Department of Chemical and Biomolecular Engineering, CHINA
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8
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Sayfutyarova ER, Goings JJ, Hammes-Schiffer S. Electron-Coupled Double Proton Transfer in the Slr1694 BLUF Photoreceptor: A Multireference Electronic Structure Study. J Phys Chem B 2018; 123:439-447. [DOI: 10.1021/acs.jpcb.8b10973] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Elvira R. Sayfutyarova
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Joshua J. Goings
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
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9
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Goings JJ, Reinhardt CR, Hammes-Schiffer S. Propensity for Proton Relay and Electrostatic Impact of Protein Reorganization in Slr1694 BLUF Photoreceptor. J Am Chem Soc 2018; 140:15241-15251. [DOI: 10.1021/jacs.8b07456] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Joshua J. Goings
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Clorice R. Reinhardt
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Sharon Hammes-Schiffer
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
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10
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Abstract
The first stage in biological signaling is based on changes in the functional state of a receptor protein triggered by interaction of the receptor with its ligand(s). The light-triggered nature of photoreceptors allows studies on the mechanism of such changes in receptor proteins using a wide range of biophysical methods and with superb time resolution. Here, we critically evaluate current understanding of proton and electron transfer in photosensory proteins and their involvement both in primary photochemistry and subsequent processes that lead to the formation of the signaling state. An insight emerging from multiple families of photoreceptors is that ultrafast primary photochemistry is followed by slower proton transfer steps that contribute to triggering large protein conformational changes during signaling state formation. We discuss themes and principles for light sensing shared by the six photoreceptor families: rhodopsins, phytochromes, photoactive yellow proteins, light-oxygen-voltage proteins, blue-light sensors using flavin, and cryptochromes.
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Affiliation(s)
- Tilman Kottke
- Department of Chemistry, Bielefeld University, 33615 Bielefeld, Germany
| | - Aihua Xie
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
| | - Delmar S. Larsen
- Department of Chemistry, University of California, Davis, California 95616, USA
| | - Wouter D. Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma 74078, USA
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11
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Fujisawa T, Masuda S. Light-induced chromophore and protein responses and mechanical signal transduction of BLUF proteins. Biophys Rev 2017; 10:327-337. [PMID: 29235080 PMCID: PMC5899715 DOI: 10.1007/s12551-017-0355-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/15/2017] [Indexed: 11/26/2022] Open
Abstract
Photoreceptor proteins have been used to study how protein conformational changes are induced by alterations in their environments and how their signals are transmitted to downstream factors to dictate physiological responses. These proteins are attractive models because their signal transduction aspects and structural changes can be precisely regulated in vivo and in vitro based on light intensity. Among the known photoreceptors, members of the blue light–using flavin (BLUF) protein family have been well characterized with regard to how they control various light-dependent physiological responses in several microorganisms. Herein, we summarize our current understanding of their photoactivation and signal-transduction mechanisms. For signal transduction, we review recent studies concerning how the BLUF protein, PixD, transmits a light-induced signal to its downstream factor, PixE, to modulate phototaxis of the cyanobacterium Synechocystis sp. PCC6803.
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Affiliation(s)
- Tomotsumi Fujisawa
- Department of Chemistry, Graduate School of Science and Engineering, Saga University, Saga, 840-8502 Japan
| | - Shinji Masuda
- Center for Biological Resources & Informatics, Tokyo Institute of Technology, Yokohama, 226-8501 Japan
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12
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Gil AA, Laptenok SP, Iuliano JN, Lukacs A, Verma A, Hall CR, Yoon GE, Brust R, Greetham GM, Towrie M, French JB, Meech SR, Tonge PJ. Photoactivation of the BLUF Protein PixD Probed by the Site-Specific Incorporation of Fluorotyrosine Residues. J Am Chem Soc 2017; 139:14638-14648. [PMID: 28876066 DOI: 10.1021/jacs.7b07849] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The flavin chromophore in blue-light-using FAD (BLUF) photoreceptors is surrounded by a hydrogen bond network that senses and responds to changes in the electronic structure of the flavin on the ultrafast time scale. The hydrogen bond network includes a strictly conserved Tyr residue, and previously we explored the role of this residue, Y21, in the photoactivation mechanism of the BLUF protein AppABLUF by the introduction of fluorotyrosine (F-Tyr) analogues that modulated the pKa and reduction potential of Y21 by 3.5 pH units and 200 mV, respectively. Although little impact on the forward (dark- to light-adapted form) photoreaction was observed, the change in Y21 pKa led to a 4000-fold increase in the rate of dark-state recovery. In the present work we have extended these studies to the BLUF protein PixD, where, in contrast to AppABLUF, modulation in the Tyr (Y8) pKa has a profound impact on the forward photoreaction. In particular, a decrease in Y8 pKa by 2 or more pH units prevents formation of a stable light state, consistent with a photoactivation mechanism that involves proton transfer or proton-coupled electron transfer from Y8 to the electronically excited FAD. Conversely, the effect of pKa on the rate of dark recovery is markedly reduced in PixD. These observations highlight very significant differences between the photocycles of PixD and AppABLUF, despite their sharing highly conserved FAD binding architectures.
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Affiliation(s)
| | - Sergey P Laptenok
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | | | - Andras Lukacs
- Department of Biophysics, Medical School, University of Pecs , Pecs H-7622, Hungary
| | - Anil Verma
- Central Laser Facility, Harwell Science and Innovation Campus , Didcot, Oxon OX11 0QX, U.K
| | - Christopher R Hall
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | | | | | - Gregory M Greetham
- Central Laser Facility, Harwell Science and Innovation Campus , Didcot, Oxon OX11 0QX, U.K
| | - Michael Towrie
- Central Laser Facility, Harwell Science and Innovation Campus , Didcot, Oxon OX11 0QX, U.K
| | | | - Stephen R Meech
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
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13
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Hadži S, Garcia-Pino A, Haesaerts S, Jurenas D, Gerdes K, Lah J, Loris R. Ribosome-dependent Vibrio cholerae mRNAse HigB2 is regulated by a β-strand sliding mechanism. Nucleic Acids Res 2017; 45:4972-4983. [PMID: 28334932 PMCID: PMC5416850 DOI: 10.1093/nar/gkx138] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 02/25/2017] [Indexed: 11/12/2022] Open
Abstract
Toxin–antitoxin (TA) modules are small operons involved in bacterial stress response and persistence. higBA operons form a family of TA modules with an inverted gene organization and a toxin belonging to the RelE/ParE superfamily. Here, we present the crystal structures of chromosomally encoded Vibrio cholerae antitoxin (VcHigA2), toxin (VcHigB2) and their complex, which show significant differences in structure and mechanisms of function compared to the higBA module from plasmid Rts1, the defining member of the family. The VcHigB2 is more closely related to Escherichia coli RelE both in terms of overall structure and the organization of its active site. VcHigB2 is neutralized by VcHigA2, a modular protein with an N-terminal intrinsically disordered toxin-neutralizing segment followed by a C-terminal helix-turn-helix dimerization and DNA binding domain. VcHigA2 binds VcHigB2 with picomolar affinity, which is mainly a consequence of entropically favorable de-solvation of a large hydrophobic binding interface and enthalpically favorable folding of the N-terminal domain into an α-helix followed by a β-strand. This interaction displaces helix α3 of VcHigB2 and at the same time induces a one-residue shift in the register of β-strand β3, thereby flipping the catalytically important Arg64 out of the active site.
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Affiliation(s)
- San Hadži
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, B-1050 Brussel, Belgium.,Molecular Recognition Unit, Center for Structural Biology, Vlaams Instituut voor Biotechnologie, B-1050 Brussel, Belgium.,Department of Physical Chemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Abel Garcia-Pino
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, B-1050 Brussel, Belgium.,Biologie Structurale et Biophysique, IBMM-DBM, Université Libre de Bruxelles (ULB), B-6041 Gosselies, Belgium
| | - Sarah Haesaerts
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, B-1050 Brussel, Belgium.,Molecular Recognition Unit, Center for Structural Biology, Vlaams Instituut voor Biotechnologie, B-1050 Brussel, Belgium
| | - Dukas Jurenas
- Biologie Structurale et Biophysique, IBMM-DBM, Université Libre de Bruxelles (ULB), B-6041 Gosselies, Belgium
| | - Kenn Gerdes
- Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Jurij Lah
- Department of Physical Chemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Remy Loris
- Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, B-1050 Brussel, Belgium.,Molecular Recognition Unit, Center for Structural Biology, Vlaams Instituut voor Biotechnologie, B-1050 Brussel, Belgium
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14
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Sebastián M, Lira-Navarrete E, Serrano A, Marcuello C, Velázquez-Campoy A, Lostao A, Hurtado-Guerrero R, Medina M, Martínez-Júlvez M. The FAD synthetase from the human pathogen Streptococcus pneumoniae: a bifunctional enzyme exhibiting activity-dependent redox requirements. Sci Rep 2017; 7:7609. [PMID: 28790457 PMCID: PMC5548840 DOI: 10.1038/s41598-017-07716-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 06/28/2017] [Indexed: 11/12/2022] Open
Abstract
Prokaryotic bifunctional FAD synthetases (FADSs) catalyze the biosynthesis of FMN and FAD, whereas in eukaryotes two enzymes are required for the same purpose. FMN and FAD are key cofactors to maintain the flavoproteome homeostasis in all type of organisms. Here we shed light to the properties of the hitherto unstudied bacterial FADS from the human pathogen Streptococcus pneumoniae (SpnFADS). As other members of the family, SpnFADS catalyzes the three typical activities of prokaryotic FADSs: riboflavin kinase (RFK), ATP:FMN:adenylyltransferase (FMNAT), and FAD pyrophosphorylase (FADpp). However, several SpnFADS biophysical properties differ from those of other family members. In particular; i) the RFK activity is not inhibited by the riboflavin (RF) substrate, ii) the FMNAT and FADSpp activities require flavin substrates in the reduced state, iii) binding of adenine nucleotide ligands is required for the binding of flavinic substrates/products and iv) the monomer is the preferred state. Collectively, our results add interesting mechanistic differences among the few prokaryotic bifunctional FADSs already characterized, which might reflect the adaptation of the enzyme to relatively different environments. In a health point of view, differences among FADS family members provide us with a framework to design selective compounds targeting these enzymes for the treatment of diverse infectious diseases.
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Affiliation(s)
- María Sebastián
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain.,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain
| | - Erandi Lira-Navarrete
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.,Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, School of Dentistry, University of Copenhagen, Copenhagen, DK-2200, Denmark
| | - Ana Serrano
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain.,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040, Madrid, Spain
| | - Carlos Marcuello
- Laboratorio de Microscopías Avanzadas (LMA), Instituto de Nanociencia de Aragón (INA), and Fundación INA, Universidad de Zaragoza, Zaragoza, Spain.,Univ Reims, Lab Rech Nanosci, EA4682, F-51100 Reims and INRA, FARE Lab, F-51100, Reims, France
| | - Adrián Velázquez-Campoy
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain.,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.,Fundación ARAID, Diputación General de Aragón, Aragón, Spain.,Aragon Institute for Health Research (IIS Aragon), Zaragoza, 50009, Spain
| | - Anabel Lostao
- Laboratorio de Microscopías Avanzadas (LMA), Instituto de Nanociencia de Aragón (INA), and Fundación INA, Universidad de Zaragoza, Zaragoza, Spain.,Fundación ARAID, Diputación General de Aragón, Aragón, Spain
| | - Ramón Hurtado-Guerrero
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.,Fundación ARAID, Diputación General de Aragón, Aragón, Spain
| | - Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain. .,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.
| | - Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain. .,Instituto de Biocomputación y Física de Sistemas Complejos (BIFI) and GBsC-CSIC and BIFI-CSIC Joint Units, Universidad de Zaragoza, Zaragoza, Spain.
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15
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Molecular mechanism of photoactivation of a light-regulated adenylate cyclase. Proc Natl Acad Sci U S A 2017; 114:8562-8567. [PMID: 28739908 DOI: 10.1073/pnas.1704391114] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The photoactivated adenylate cyclase (PAC) from the photosynthetic cyanobacterium Oscillatoria acuminata (OaPAC) detects light through a flavin chromophore within the N-terminal BLUF domain. BLUF domains have been found in a number of different light-activated proteins, but with different relative orientations. The two BLUF domains of OaPAC are found in close contact with each other, forming a coiled coil at their interface. Crystallization does not impede the activity switching of the enzyme, but flash cooling the crystals to cryogenic temperatures prevents the signature spectral changes that occur on photoactivation/deactivation. High-resolution crystallographic analysis of OaPAC in the fully activated state has been achieved by cryocooling the crystals immediately after light exposure. Comparison of the isomorphous light- and dark-state structures shows that the active site undergoes minimal changes, yet enzyme activity may increase up to 50-fold, depending on conditions. The OaPAC models will assist the development of simple, direct means to raise the cyclic AMP levels of living cells by light, and other tools for optogenetics.
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16
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Park SY, Tame JRH. Seeing the light with BLUF proteins. Biophys Rev 2017; 9:169-176. [PMID: 28510088 DOI: 10.1007/s12551-017-0258-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 03/05/2017] [Indexed: 10/19/2022] Open
Abstract
First described about 15 years ago, BLUF (Blue Light Using Flavin) domains are light-triggered switches that control enzyme activity or gene expression in response to blue light, remaining activated for seconds or even minutes after stimulation. The conserved, ferredoxin-like fold holds a flavin chromophore that captures the light and somehow triggers downstream events. BLUF proteins are found in both prokaryotes and eukaryotes and have a variety of architectures and oligomeric forms, but the BLUF domain itself seems to have a well-preserved structure and mechanism that have been the focus of intense study for a number of years. Crystallographic and NMR structures of BLUF domains have been solved, but the conflicting models have led to considerable debate about the atomic details of photo-activation. Advanced spectroscopic and computational methods have been used to analyse the early events after photon absorption, but these too have led to widely differing conclusions. New structural models are improving our understanding of the details of the mechanism and may lead to novel tailor-made tools for optogenetics.
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Affiliation(s)
- Sam-Yong Park
- Drug Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045, Japan
| | - Jeremy R H Tame
- Drug Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045, Japan.
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