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Boussac A, Sugiura M, Nakamura M, Nagao R, Noguchi T, Viola S, Rutherford AW, Sellés J. Absorption changes in Photosystem II in the Soret band region upon the formation of the chlorophyll cation radical [P D1P D2] . PHOTOSYNTHESIS RESEARCH 2023:10.1007/s11120-023-01049-3. [PMID: 37751034 DOI: 10.1007/s11120-023-01049-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/07/2023] [Indexed: 09/27/2023]
Abstract
Flash-induced absorption changes in the Soret region arising from the [PD1PD2]+ state, the chlorophyll cation radical formed upon light excitation of Photosystem II (PSII), were measured in Mn-depleted PSII cores at pH 8.6. Under these conditions, TyrD is i) reduced before the first flash, and ii) oxidized before subsequent flashes. In wild-type PSII, when TyrD● is present, an additional signal in the [PD1PD2]+-minus-[PD1PD2] difference spectrum was observed when compared to the first flash when TyrD is not oxidized. The additional feature was "W-shaped" with troughs at 434 nm and 446 nm. This feature was absent when TyrD was reduced, but was present (i) when TyrD was physically absent (and replaced by phenylalanine) or (ii) when its H-bonding histidine (D2-His189) was physically absent (replaced by a Leucine). Thus, the simple difference spectrum without the double trough feature at 434 nm and 446 nm, seemed to require the native structural environment around the reduced TyrD and its H bonding partners to be present. We found no evidence of involvement of PD1, ChlD1, PheD1, PheD2, TyrZ, and the Cytb559 heme in the W-shaped difference spectrum. However, the use of a mutant of the PD2 axial His ligand, the D2-His197Ala, shows that the PD2 environment seems involved in the formation of "W-shaped" signal.
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Affiliation(s)
- Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR9198, CEA Saclay, 91191, Gif-Sur-Yvette, France.
| | - Miwa Sugiura
- Proteo-Science Research Center, and Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-Cho, Matsuyama, Ehime, 790-8577, Japan
| | - Makoto Nakamura
- Proteo-Science Research Center, and Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-Cho, Matsuyama, Ehime, 790-8577, Japan
| | - Ryo Nagao
- Faculty of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Takumi Noguchi
- Department of Physics, Graduate School of Science, Nagoya University, Furo-Cho, Chikusa-Ku, Nagoya, 464-8602, Japan
| | - Stefania Viola
- Institut de Biosciences Et Biotechnologies, UMR 7265, Aix-Marseille, CEA Cadarache, Cité des Énergies, 13115, Saint-Paul-Lez-Durance, France
| | | | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 Rue Pierre Et Marie Curie, 75005, Paris, France
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Murotomi K, Umeno A, Shichiri M, Tanito M, Yoshida Y. Significance of Singlet Oxygen Molecule in Pathologies. Int J Mol Sci 2023; 24:ijms24032739. [PMID: 36769060 PMCID: PMC9917472 DOI: 10.3390/ijms24032739] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 01/22/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
Reactive oxygen species, including singlet oxygen, play an important role in the onset and progression of disease, as well as in aging. Singlet oxygen can be formed non-enzymatically by chemical, photochemical, and electron transfer reactions, or as a byproduct of endogenous enzymatic reactions in phagocytosis during inflammation. The imbalance of antioxidant enzymes and antioxidant networks with the generation of singlet oxygen increases oxidative stress, resulting in the undesirable oxidation and modification of biomolecules, such as proteins, DNA, and lipids. This review describes the molecular mechanisms of singlet oxygen production in vivo and methods for the evaluation of damage induced by singlet oxygen. The involvement of singlet oxygen in the pathogenesis of skin and eye diseases is also discussed from the biomolecular perspective. We also present our findings on lipid oxidation products derived from singlet oxygen-mediated oxidation in glaucoma, early diabetes patients, and a mouse model of bronchial asthma. Even in these diseases, oxidation products due to singlet oxygen have not been measured clinically. This review discusses their potential as biomarkers for diagnosis. Recent developments in singlet oxygen scavengers such as carotenoids, which can be utilized to prevent the onset and progression of disease, are also described.
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Affiliation(s)
- Kazutoshi Murotomi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan
| | - Aya Umeno
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan
| | - Mototada Shichiri
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda 563-8577, Japan
- Correspondence: ; Tel.: +81-72-751-8234
| | - Masaki Tanito
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan
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Boussac A, Sellés J, Hamon M, Sugiura M. Properties of Photosystem II lacking the PsbJ subunit. PHOTOSYNTHESIS RESEARCH 2022; 152:347-361. [PMID: 34661808 DOI: 10.1007/s11120-021-00880-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
Photosystem II (PSII), the oxygen-evolving enzyme, consists of 17 trans-membrane and 3 extrinsic membrane proteins. Other subunits bind to PSII during assembly, like Psb27, Psb28, and Tsl0063. The presence of Psb27 has been proposed (Zabret et al. in Nat Plants 7:524-538, 2021; Huang et al. Proc Natl Acad Sci USA 118:e2018053118, 2021; Xiao et al. in Nat Plants 7:1132-1142, 2021) to prevent the binding of PsbJ, a single transmembrane α-helix close to the quinone QB binding site. Consequently, a PSII rid of Psb27, Psb28, and Tsl0034 prior to the binding of PsbJ would logically correspond to an assembly intermediate. The present work describes experiments aiming at further characterizing such a ∆PsbJ-PSII, purified from the thermophilic Thermosynechococcus elongatus, by means of MALDI-TOF spectroscopy, thermoluminescence, EPR spectroscopy, and UV-visible time-resolved spectroscopy. In the purified ∆PsbJ-PSII, an active Mn4CaO5 cluster is present in 60-70% of the centers. In these centers, although the forward electron transfer seems not affected, the Em of the QB/QB- couple increases by ≥ 120 mV , thus disfavoring the electron coming back on QA. The increase of the energy gap between QA/QA- and QB/QB- could contribute in a protection against the charge recombination between the donor side and QB-, identified at the origin of photoinhibition under low light (Keren et al. in Proc Natl Acad Sci USA 94:1579-1584, 1997), and possibly during the slow photoactivation process.
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Affiliation(s)
- Alain Boussac
- I2BC, UMR CNRS 9198, CEA Saclay, 91191, Gif-sur-Yvette, France.
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Marion Hamon
- Institut de Biologie Physico-Chimique, UMR8226/FRC550 CNRS and Sorbonne-Université, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Miwa Sugiura
- Proteo-Science Research Center, and Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan.
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Viola S, Roseby W, Santabarbara S, Nürnberg D, Assunção R, Dau H, Sellés J, Boussac A, Fantuzzi A, Rutherford AW. Impact of energy limitations on function and resilience in long-wavelength Photosystem II. eLife 2022; 11:79890. [PMID: 35852834 PMCID: PMC9439682 DOI: 10.7554/elife.79890] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/18/2022] [Indexed: 01/06/2023] Open
Abstract
Photosystem II (PSII) uses the energy from red light to split water and reduce quinone, an energy-demanding process based on chlorophyll a (Chl-a) photochemistry. Two types of cyanobacterial PSII can use chlorophyll d (Chl-d) and chlorophyll f (Chl-f) to perform the same reactions using lower energy, far-red light. PSII from Acaryochloris marina has Chl-d replacing all but one of its 35 Chl-a, while PSII from Chroococcidiopsis thermalis, a facultative far-red species, has just 4 Chl-f and 1 Chl-d and 30 Chl-a. From bioenergetic considerations, the far-red PSII were predicted to lose photochemical efficiency and/or resilience to photodamage. Here, we compare enzyme turnover efficiency, forward electron transfer, back-reactions and photodamage in Chl-f-PSII, Chl-d-PSII, and Chl-a-PSII. We show that: (i) all types of PSII have a comparable efficiency in enzyme turnover; (ii) the modified energy gaps on the acceptor side of Chl-d-PSII favour recombination via PD1+Phe- repopulation, leading to increased singlet oxygen production and greater sensitivity to high-light damage compared to Chl-a-PSII and Chl-f-PSII; (iii) the acceptor-side energy gaps in Chl-f-PSII are tuned to avoid harmful back reactions, favouring resilience to photodamage over efficiency of light usage. The results are explained by the differences in the redox tuning of the electron transfer cofactors Phe and QA and in the number and layout of the chlorophylls that share the excitation energy with the primary electron donor. PSII has adapted to lower energy in two distinct ways, each appropriate for its specific environment but with different functional penalties.
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Affiliation(s)
- Stefania Viola
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
| | - William Roseby
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
| | | | | | | | - Holger Dau
- Physics Department, Freie Universität BerlinBerlinGermany
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne UniversitéParisFrance
| | - Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR9198, CEA SaclayGif-Sur-YvetteFrance
| | - Andrea Fantuzzi
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
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A metabolomic study of Gomphrena agrestis in Brazilian Cerrado suggests drought-adaptive strategies on metabolism. Sci Rep 2021; 11:12933. [PMID: 34155311 PMCID: PMC8217525 DOI: 10.1038/s41598-021-92449-9] [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: 12/23/2020] [Accepted: 06/03/2021] [Indexed: 11/23/2022] Open
Abstract
Drought is the main factor that limits the distribution and productivity of plant species. In the Brazilian Cerrado, the vegetation is adapted to a seasonal climate with long- and short-term periods of drought. To analyze the metabolic strategies under such conditions, a metabolomic approach was used to characterize Gomphrena agrestis Mart. (Amaranthaceae) a native species that grows under natural conditions, in a rock-field area. Roots and leaves material from native specimens were sampled along different seasons of the year and LC–MS and GC–MS analyzed for multiple chemical constituents. The datasets derived from the different measurements were combined and evaluated using multivariate analysis. Principal component analysis was used to obtain an overview of the samples and identify outliers. Later, the data was analyzed with orthogonal projection to latent structures discriminant analysis to obtain valid models that could explain the metabolite variations in the different seasons. Two hundred and eighty metabolites were annotated, generating a unique database to characterize metabolic strategies used to cope with the effects of drought. The accumulation of fructans in the thickened roots is consistent with the storage of carbons during the rainy season to support the energy demand during a long period of drought. The accumulation of Abscisic acid, sugars and sugar alcohols, phenolics, and pigment in the leaves suggests physiological adaptations. To cope with long-term drought, the data suggests that tissue water status and storage of reserves are important to support plant survival and regrowth. However, during short-term drought, osmoregulation and oxidative protection seems to be essential, probably to support the maintenance of active photosynthesis.
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Tocopherol controls D1 amino acid oxidation by oxygen radicals in Photosystem II. Proc Natl Acad Sci U S A 2021; 118:2019246118. [PMID: 33479170 DOI: 10.1073/pnas.2019246118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Photosystem II (PSII) is an intrinsic membrane protein complex that functions as a light-driven water:plastoquinone oxidoreductase in oxygenic photosynthesis. Electron transport in PSII is associated with formation of reactive oxygen species (ROS) responsible for oxidative modifications of PSII proteins. In this study, oxidative modifications of the D1 and D2 proteins by the superoxide anion (O2 •-) and the hydroxyl (HO•) radicals were studied in WT and a tocopherol cyclase (vte1) mutant, which is deficient in the lipid-soluble antioxidant α-tocopherol. In the absence of this antioxidant, high-resolution tandem mass spectrometry was used to identify oxidation of D1:130E to hydroxyglutamic acid by O2 •- at the PheoD1 site. Additionally, D1:246Y was modified to either tyrosine hydroperoxide or dihydroxyphenylalanine by O2 •- and HO•, respectively, in the vicinity of the nonheme iron. We propose that α-tocopherol is localized near PheoD1 and the nonheme iron, with its chromanol head exposed to the lipid-water interface. This helps to prevent oxidative modification of the amino acid's hydrogen that is bonded to PheoD1 and the nonheme iron (via bicarbonate), and thus protects electron transport in PSII from ROS damage.
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Sugiura M, Taniguchi T, Tango N, Nakamura M, Sellés J, Boussac A. Probing the role of arginine 323 of the D1 protein in photosystem II function. PHYSIOLOGIA PLANTARUM 2021; 171:183-199. [PMID: 32359083 DOI: 10.1111/ppl.13115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 06/11/2023]
Abstract
The Mn4 CaO5 cluster of photosystem II (PSII) advances sequentially through five oxidation states (S0 to S4 ). Under the enzyme cycle, two water molecules are oxidized, O2 is generated and four protons are released into the lumen. Umena et al. (2011) have proposed that, with other charged amino acids, the R323 residue of the D1 protein could contribute to regulate a proton egress pathway from the Mn4 CaO5 cluster and TyrZ via a proton channel identified from the 3D structure. To test this suggestion, a PsbA3/R323E site-directed mutant has been constructed and the properties of its PSII have been compared to those of the PsbA3-PSII by using EPR spectroscopy, polarography, thermoluminescence and time-resolved UV-visible absorption spectroscopy. Neither the oscillations with a period four nor the kinetics and S-state-dependent stoichiometry of the proton release were affected. However, several differences have been found: (1) the P680 + decay in the hundreds of ns time domain was much slower in the mutant, (2) the S2 QA - /DCMU and S3 QA - /DCMU radiative charge recombination occurred at higher temperatures and (3) the S0 TyrZ • , S1 TyrZ • , S2 TyrZ • split EPR signals induced at 4.2 K by visible light from the S0 TyrZ , S1 TyrZ , S2 TyrZ , respectively, and the (S2 TyrZ • )' induced by NIR illumination at 4.2 K of the S3 TyrZ state differed. It is proposed that the R323 residue of the D1 protein interacts with TyrZ likely via the H-bond network previously proposed to be a proton channel. Therefore, rather than participating in the egress of protons to the lumen, this channel could be involved in the relaxations of the H-bonds around TyrZ by interacting with the bulk, thus tuning the driving force required for TyrZ oxidation.
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Affiliation(s)
- Miwa Sugiura
- Proteo-Science Research Center, Ehime University, Matsuyama, 790-8577, Japan
| | - Tomonori Taniguchi
- Department of Chemistry, Graduate School of Science and Technology, Ehime University, Matsuyama, 790-8577, Japan
| | - Nanami Tango
- Department of Chemistry, Graduate School of Science and Technology, Ehime University, Matsuyama, 790-8577, Japan
| | - Makoto Nakamura
- Department of Chemistry, Graduate School of Science and Technology, Ehime University, Matsuyama, 790-8577, Japan
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, Paris, 75005, France
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Boussac A, Sellés J, Sugiura M. What can we still learn from the electrochromic band-shifts in Photosystem II? BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148176. [PMID: 32061653 DOI: 10.1016/j.bbabio.2020.148176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 01/29/2020] [Accepted: 02/10/2020] [Indexed: 11/17/2022]
Abstract
Electrochromic band-shifts have been investigated in Photosystem II (PSII) from Thermosynechoccocus elongatus. Firstly, by using Mn-depleted PsbA1-PSII and PsbA3-PSII in which the QX absorption of PheD1 differs, a band-shift in the QX region of PheD2 centered at ~ 544 nm has been identified upon the oxidation, at pH 8.6, of TyrD. In contrast, a band-shift due to the formation of either QA•- or TyrZ• is observed in PsbA3-PSII at ~ 546 nm, as expected with E130 H-bonded to PheD1 and at ~ 544 nm as expected with Q130 H-bonded to PheD1. Secondly, electrochromic band-shifts in the Chla Soret region have been measured in O2-evolving PSII in PsbA3-PSII, in the PsbA3/H198Q mutant in which the Soret band of PD1 is blue shifted and in the PsbA3/T179H mutant. Upon TyrZ•QA•- formation the Soret band of PD1 is red shifted and the Soret band of ChlD1 is blue shifted. In contrast, only PD1 undergoes a detectable S-state dependent electrochromism. Thirdly, the time resolved S-state dependent electrochromism attributed to PD1 is biphasic for all the S-state transitions except for S1 to S2, and shows that: i) the proton release in S0 to S1 occurs after the electron transfer and ii) the proton release and the electron transfer kinetics in S2 to S3, in T. elongatus, are significantly faster than often considered. The nature of S2TyrZ• is discussed in view of the models in the literature involving intermediate states in the S2 to S3 transition.
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Affiliation(s)
- Alain Boussac
- I(2)BC, CNRS UMR 9198, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, CNRS UMR 7141 and Sorbonne Université, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Miwa Sugiura
- Proteo-Science Research Center and Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
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Hamilton TL. The trouble with oxygen: The ecophysiology of extant phototrophs and implications for the evolution of oxygenic photosynthesis. Free Radic Biol Med 2019; 140:233-249. [PMID: 31078729 DOI: 10.1016/j.freeradbiomed.2019.05.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 04/03/2019] [Accepted: 05/02/2019] [Indexed: 12/11/2022]
Abstract
The ability to harvest light to drive chemical reactions and gain energy provided microbes access to high energy electron donors which fueled primary productivity, biogeochemical cycles, and microbial evolution. Oxygenic photosynthesis is often cited as the most important microbial innovation-the emergence of oxygen-evolving photosynthesis, aided by geologic events, is credited with tipping the scale from a reducing early Earth to an oxygenated world that eventually lead to complex life. Anoxygenic photosynthesis predates oxygen-evolving photosynthesis and played a key role in developing and fine-tuning the photosystem architecture of modern oxygenic phototrophs. The release of oxygen as a by-product of metabolic activity would have caused oxidative damage to anaerobic microbiota that evolved under the anoxic, reducing conditions of early Earth. Photosynthetic machinery is particularly susceptible to the adverse effects of oxygen and reactive oxygen species and these effects are compounded by light. As a result, phototrophs employ additional detoxification mechanisms to mitigate oxidative stress and have evolved alternative oxygen-dependent enzymes for chlorophyll biosynthesis. Phylogenetic reconstruction studies and biochemical characterization suggest photosynthetic reactions centers, particularly in Cyanobacteria, evolved to both increase efficiency of electron transfer and avoid photodamage caused by chlorophyll radicals that is acute in the presence of oxygen. Here we review the oxygen and reactive oxygen species detoxification mechanisms observed in extant anoxygenic and oxygenic photosynthetic bacteria as well as the emergence of these mechanisms over evolutionary time. We examine the distribution of phototrophs in modern systems and phylogenetic reconstructions to evaluate the emergence of mechanisms to mediate oxidative damage and highlight changes in photosystems and reaction centers, chlorophyll biosynthesis, and niche space in response to oxygen production. This synthesis supports an emergence of H2S-driven anoxygenic photosynthesis in Cyanobacteria prior to the evolution of oxygenic photosynthesis and underscores a role for the former metabolism in fueling fine-tuning of the oxygen evolving complex and mechanisms to repair oxidative damage. In contrast, we note the lack of elaborate mechanisms to deal with oxygen in non-cyanobacterial anoxygenic phototrophs suggesting these microbes have occupied similar niche space throughout Earth's history.
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Affiliation(s)
- Trinity L Hamilton
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, 55108, USA; Biotechnology Institute, University of Minnesota, St. Paul, MN, 55108, USA.
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Abstract
Sam Granick opened his seminal 1957 paper titled 'Speculations on the origins and evolution of photosynthesis' with the assertion that there is a constant urge in human beings to seek beginnings (I concur). This urge has led to an incessant stream of speculative ideas and debates on the evolution of photosynthesis that started in the first half of the twentieth century and shows no signs of abating. Some of these speculative ideas have become commonplace, are taken as fact, but find little support. Here, I review and scrutinize three widely accepted ideas that underpin the current study of the evolution of photosynthesis: first, that the photochemical reaction centres used in anoxygenic photosynthesis are more primitive than those in oxygenic photosynthesis; second, that the probability of acquiring photosynthesis via horizontal gene transfer is greater than the probability of losing photosynthesis; and third, and most important, that the origin of anoxygenic photosynthesis pre-dates the origin of oxygenic photosynthesis. I shall attempt to demonstrate that these three ideas are often grounded in incorrect assumptions built on more assumptions with no experimental or observational support. I hope that this brief review will not only serve as a cautionary tale but also that it will open new avenues of research aimed at disentangling the complex evolution of photosynthesis and its impact on the early history of life and the planet.
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Affiliation(s)
- Tanai Cardona
- Department of Life Sciences, Imperial College London, London, UK
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Takegawa Y, Nakamura M, Nakamura S, Noguchi T, Sellés J, Rutherford AW, Boussac A, Sugiura M. New insights on Chl D1 function in Photosystem II from site-directed mutants of D1/T179 in Thermosynechococcus elongatus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:297-309. [PMID: 30703365 DOI: 10.1016/j.bbabio.2019.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/17/2018] [Accepted: 01/26/2019] [Indexed: 01/16/2023]
Abstract
The monomeric chlorophyll, ChlD1, which is located between the PD1PD2 chlorophyll pair and the pheophytin, PheoD1, is the longest wavelength chlorophyll in the heart of Photosystem II and is thought to be the primary electron donor. Its central Mg2+ is liganded to a water molecule that is H-bonded to D1/T179. Here, two site-directed mutants, D1/T179H and D1/T179V, were made in the thermophilic cyanobacterium, Thermosynechococcus elongatus, and characterized by a range of biophysical techniques. The Mn4CaO5 cluster in the water-splitting site is fully active in both mutants. Changes in thermoluminescence indicate that i) radiative recombination occurs via the repopulation of *ChlD1 itself; ii) non-radiative charge recombination reactions appeared to be faster in the T179H-PSII; and iii) the properties of PD1PD2 were unaffected by this mutation, and consequently iv) the immediate precursor state of the radiative excited state is the ChlD1+PheoD1- radical pair. Chlorophyll bleaching due to high intensity illumination correlated with the amount of 1O2 generated. Comparison of the bleaching spectra with the electrochromic shifts attributed to ChlD1 upon QA- formation, indicates that in the T179H-PSII and in the WT*3-PSII, the ChlD1 itself is the chlorophyll that is first damaged by 1O2, whereas in the T179V-PSII a more red chlorophyll is damaged, the identity of which is discussed. Thus, ChlD1 appears to be one of the primary damage site in recombination-mediated photoinhibition. Finally, changes in the absorption of ChlD1 very likely contribute to the well-known electrochromic shifts observed at ~430 nm during the S-state cycle.
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Affiliation(s)
- Yuki Takegawa
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Makoto Nakamura
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Shin Nakamura
- Division of Material Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Takumi Noguchi
- Division of Material Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | | | - Alain Boussac
- I(2)BC, UMR CNRS 9198, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Miwa Sugiura
- Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan; Proteo-Science Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan.
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12
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Nürnberg DJ, Morton J, Santabarbara S, Telfer A, Joliot P, Antonaru LA, Ruban AV, Cardona T, Krausz E, Boussac A, Fantuzzi A, Rutherford AW. Photochemistry beyond the red limit in chlorophyll f-containing photosystems. Science 2018; 360:1210-1213. [PMID: 29903971 DOI: 10.1126/science.aar8313] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/18/2018] [Indexed: 11/02/2022]
Abstract
Photosystems I and II convert solar energy into the chemical energy that powers life. Chlorophyll a photochemistry, using red light (680 to 700 nm), is near universal and is considered to define the energy "red limit" of oxygenic photosynthesis. We present biophysical studies on the photosystems from a cyanobacterium grown in far-red light (750 nm). The few long-wavelength chlorophylls present are well resolved from each other and from the majority pigment, chlorophyll a. Charge separation in photosystem I and II uses chlorophyll f at 745 nm and chlorophyll f (or d) at 727 nm, respectively. Each photosystem has a few even longer-wavelength chlorophylls f that collect light and pass excitation energy uphill to the photochemically active pigments. These photosystems function beyond the red limit using far-red pigments in only a few key positions.
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Affiliation(s)
| | | | - Stefano Santabarbara
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, via Celoria 26, 20133 Milano, Italy
| | - Alison Telfer
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Pierre Joliot
- Institut de Biologie Physico-Chimique, Unité Mixte de Recherche 7141 Centre National de la Recherche Scientifique-Université Pierre et Marie Curie, 13 Rue Pierre et Marie Curie, 75005 Paris, France
| | - Laura A Antonaru
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Alexander V Ruban
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, UK
| | - Tanai Cardona
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Elmars Krausz
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, via Celoria 26, 20133 Milano, Italy
| | - Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR 9198, Bât 532, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Andrea Fantuzzi
- Department of Life Sciences, Imperial College, London SW7 2AZ, UK.
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Sugiura M, Ozaki Y, Rappaport F, Boussac A. Corrigendum to "Influence of Histidine-198 of the D1 subunit on the properties of the primary electron donor, P 680 , of photosystem II in Thermosynechococcus elongatus". BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1943-1948. [DOI: 10.1016/j.bbabio.2016.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 09/26/2016] [Accepted: 09/28/2016] [Indexed: 11/25/2022]
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Bicarbonate-induced redox tuning in Photosystem II for regulation and protection. Proc Natl Acad Sci U S A 2016; 113:12144-12149. [PMID: 27791001 DOI: 10.1073/pnas.1608862113] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The midpoint potential (Em) of [Formula: see text], the one-electron acceptor quinone of Photosystem II (PSII), provides the thermodynamic reference for calibrating PSII bioenergetics. Uncertainty exists in the literature, with two values differing by ∼80 mV. Here, we have resolved this discrepancy by using spectroelectrochemistry on plant PSII-enriched membranes. Removal of bicarbonate (HCO3-) shifts the Em from ∼-145 mV to -70 mV. The higher values reported earlier are attributed to the loss of HCO3- during the titrations (pH 6.5, stirred under argon gassing). These findings mean that HCO3- binds less strongly when QA-• is present. Light-induced QA-• formation triggered HCO3- loss as manifest by the slowed electron transfer and the upshift in the Em of QA HCO3--depleted PSII also showed diminished light-induced 1O2 formation. This finding is consistent with a model in which the increase in the Em of [Formula: see text] promotes safe, direct [Formula: see text] charge recombination at the expense of the damaging back-reaction route that involves chlorophyll triplet-mediated 1O2 formation [Johnson GN, et al. (1995) Biochim Biophys Acta 1229:202-207]. These findings provide a redox tuning mechanism, in which the interdependence of the redox state of QA and the binding by HCO3- regulates and protects PSII. The potential for a sink (CO2) to source (PSII) feedback mechanism is discussed.
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Cardona T. A fresh look at the evolution and diversification of photochemical reaction centers. PHOTOSYNTHESIS RESEARCH 2015; 126:111-34. [PMID: 25512103 PMCID: PMC4582080 DOI: 10.1007/s11120-014-0065-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 12/05/2014] [Indexed: 05/18/2023]
Abstract
In this review, I reexamine the origin and diversification of photochemical reaction centers based on the known phylogenetic relations of the core subunits, and with the aid of sequence and structural alignments. I show, for example, that the protein folds at the C-terminus of the D1 and D2 subunits of Photosystem II, which are essential for the coordination of the water-oxidizing complex, were already in place in the most ancestral Type II reaction center subunit. I then evaluate the evolution of reaction centers in the context of the rise and expansion of the different groups of bacteria based on recent large-scale phylogenetic analyses. I find that the Heliobacteriaceae family of Firmicutes appears to be the earliest branching of the known groups of phototrophic bacteria; however, the origin of photochemical reaction centers and chlorophyll synthesis cannot be placed in this group. Moreover, it becomes evident that the Acidobacteria and the Proteobacteria shared a more recent common phototrophic ancestor, and this is also likely for the Chloroflexi and the Cyanobacteria. Finally, I argue that the discrepancies among the phylogenies of the reaction center proteins, chlorophyll synthesis enzymes, and the species tree of bacteria are best explained if both types of photochemical reaction centers evolved before the diversification of the known phyla of phototrophic bacteria. The primordial phototrophic ancestor must have had both Type I and Type II reaction centers.
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Affiliation(s)
- Tanai Cardona
- Department of Life Sciences, Imperial College London, Exhibition Road, London, SW7 2AZ, UK.
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Sano Y, Endo K, Tomo T, Noguchi T. Modified molecular interactions of the pheophytin and plastoquinone electron acceptors in photosystem II of chlorophyll D-containing Acaryochloris marina as revealed by FTIR spectroscopy. PHOTOSYNTHESIS RESEARCH 2015; 125:105-114. [PMID: 25560630 DOI: 10.1007/s11120-014-0073-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/20/2014] [Indexed: 06/04/2023]
Abstract
Acaryochloris marina is a unique cyanobacterium that contains chlorophyll (Chl) d as a major pigment. Because Chl d has smaller excitation energy than Chl a used in ordinary photosynthetic organisms, the energetics of the photosystems of A. marina have been the subject of interest. It was previously shown that the redox potentials (E m's) of the redox-active pheophytin a (Pheo) and the primary plastoquinone electron acceptor (QA) in photosystem II (PSII) of A. marina are higher than those in Chl a-containing PSII, to compensate for the smaller excitation energy of Chl d (Allakhverdiev et al., Proc Natl Acad Sci USA 107: 3924-3929, 2010; ibid. 108: 8054-8058, 2011). To clarify the mechanisms of these E m increases, in this study, we have investigated the molecular interactions of Pheo and QA in PSII core complexes from A. marina using Fourier transform infrared (FTIR) spectroscopy. Light-induced FTIR difference spectra upon single reduction of Pheo and QA showed that spectral features in the regions of the keto and ester C=O stretches and the chlorin ring vibrations of Pheo and in the CO/CC stretching region of the Q A (-) semiquinone anion in A. marina are significantly different from those of the corresponding spectra in Chl a-containing cyanobacteria. These observations indicate that the molecular interactions, including the hydrogen bond interactions at the C=O groups, of these cofactors are modified in their binding sites of PSII proteins. From these results, along with the sequence information of the D1 and D2 proteins, it is suggested that A. marina tunes the E m's of Pheo and QA by altering nearby hydrogen bond networks to modify the structures of the binding pockets of these cofactors.
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Affiliation(s)
- Yuko Sano
- Division of Material Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
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Chukhutsina V, Bersanini L, Aro EM, van Amerongen H. Cyanobacterial flv4-2 Operon-Encoded Proteins Optimize Light Harvesting and Charge Separation in Photosystem II. MOLECULAR PLANT 2015; 8:747-61. [PMID: 25704162 DOI: 10.1016/j.molp.2014.12.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/09/2014] [Accepted: 12/21/2014] [Indexed: 05/11/2023]
Abstract
Photosystem II (PSII) complexes drive the water-splitting reaction necessary to transform sunlight into chemical energy. However, too much light can damage and disrupt PSII. In cyanobacteria, the flv4-2 operon encodes three proteins (Flv2, Flv4, and Sll0218), which safeguard PSII activity under air-level CO2 and in high light conditions. However, the exact mechanism of action of these proteins has not been clarified yet. We demonstrate that the PSII electron transfer properties are influenced by the flv4-2 operon-encoded proteins. Accelerated secondary charge separation kinetics was observed upon expression/overexpression of the flv4-2 operon. This is likely induced by docking of the Flv2/Flv4 heterodimer in the vicinity of the QB pocket of PSII, which, in turn, increases the QB redox potential and consequently stabilizes forward electron transfer. The alternative electron transfer route constituted by Flv2/Flv4 sequesters electrons from QB(-) guaranteeing the dissipation of excess excitation energy in PSII under stressful conditions. In addition, we demonstrate that in the absence of the flv4-2 operon-encoded proteins, about 20% of the phycobilisome antenna becomes detached from the reaction centers, thus decreasing light harvesting. Phycobilisome detachment is a consequence of a decreased relative content of PSII dimers, a feature observed in the absence of the Sll0218 protein.
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Affiliation(s)
- Volha Chukhutsina
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; MicroSpectroscopy Centre, Wageningen University, 6703HA Wageningen, The Netherlands; BioSolarCells, P.O. Box 98, 6700AB Wageningen, The Netherlands
| | - Luca Bersanini
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland
| | - Eva-Mari Aro
- Department of Biochemistry, Molecular Plant Biology, University of Turku, FI-20014 Turku, Finland
| | - Herbert van Amerongen
- Laboratory of Biophysics, Wageningen University, P.O. Box 8128, 6700 ET Wageningen, The Netherlands; MicroSpectroscopy Centre, Wageningen University, 6703HA Wageningen, The Netherlands; BioSolarCells, P.O. Box 98, 6700AB Wageningen, The Netherlands.
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Cardona T, Murray JW, Rutherford AW. Origin and Evolution of Water Oxidation before the Last Common Ancestor of the Cyanobacteria. Mol Biol Evol 2015; 32:1310-28. [PMID: 25657330 PMCID: PMC4408414 DOI: 10.1093/molbev/msv024] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Photosystem II, the water oxidizing enzyme, altered the course of evolution by filling the atmosphere with oxygen. Here, we reconstruct the origin and evolution of water oxidation at an unprecedented level of detail by studying the phylogeny of all D1 subunits, the main protein coordinating the water oxidizing cluster (Mn4CaO5) of Photosystem II. We show that D1 exists in several forms making well-defined clades, some of which could have evolved before the origin of water oxidation and presenting many atypical characteristics. The most ancient form is found in the genome of Gloeobacter kilaueensis JS-1 and this has a C-terminus with a higher sequence identity to D2 than to any other D1. Two other groups of early evolving D1 correspond to those expressed under prolonged far-red illumination and in darkness. These atypical D1 forms are characterized by a dramatically different Mn4CaO5 binding site and a Photosystem II containing such a site may assemble an unconventional metal cluster. The first D1 forms with a full set of ligands to the Mn4CaO5 cluster are grouped with D1 proteins expressed only under low oxygen concentrations and the latest evolving form is the dominant type of D1 found in all cyanobacteria and plastids. In addition, we show that the plastid ancestor had a D1 more similar to those in early branching Synechococcus. We suggest each one of these forms of D1 originated from transitional forms at different stages toward the innovation and optimization of water oxidation before the last common ancestor of all known cyanobacteria.
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Affiliation(s)
- Tanai Cardona
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - James W Murray
- Department of Life Sciences, Imperial College London, London, United Kingdom
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Chu HA, Chiu YF. The Roles of Cytochrome b 559 in Assembly and Photoprotection of Photosystem II Revealed by Site-Directed Mutagenesis Studies. FRONTIERS IN PLANT SCIENCE 2015; 6:1261. [PMID: 26793230 PMCID: PMC4709441 DOI: 10.3389/fpls.2015.01261] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/24/2015] [Indexed: 05/05/2023]
Abstract
Cytochrome b 559 (Cyt b 559) is one of the essential components of the Photosystem II reaction center (PSII). Despite recent accomplishments in understanding the structure and function of PSII, the exact physiological function of Cyt b 559 remains unclear. Cyt b 559 is not involved in the primary electron transfer pathway in PSII but may participate in secondary electron transfer pathways that protect PSII against photoinhibition. Site-directed mutagenesis studies combined with spectroscopic and functional analysis have been used to characterize Cyt b 559 mutant strains and their mutant PSII complex in higher plants, green algae, and cyanobacteria. These integrated studies have provided important in vivo evidence for possible physiological roles of Cyt b 559 in the assembly and stability of PSII, protecting PSII against photoinhibition, and modulating photosynthetic light harvesting. This mini-review presents an overview of recent important progress in site-directed mutagenesis studies of Cyt b 559 and implications for revealing the physiological functions of Cyt b 559 in PSII.
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Sugiura M, Nakamura M, Koyama K, Boussac A. Assembly of oxygen-evolving Photosystem II efficiently occurs with the apo-Cytb559 but the holo-Cytb559 accelerates the recovery of a functional enzyme upon photoinhibition. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:276-285. [PMID: 25481108 DOI: 10.1016/j.bbabio.2014.11.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/17/2014] [Accepted: 11/26/2014] [Indexed: 10/24/2022]
Abstract
Cytb559 in Photosystem II is a heterodimeric b-type cytochrome. The subunits, PsbE and PsbF, consist each in a membrane α-helix. Roles for Cytb559 remain elusive. In Thermosynechococcus elongatus, taking advantage of the robustness of the PSII variant with PsbA3 as the D1 subunit (WT*3), 4 mutants were designed hoping to get mutants nevertheless the obligatory phototrophy of this cyanobacterium. In two of them, an axial histidine ligand of the haem-iron was substituted for either a methionine, PsbE/H23M, which could be potentially a ligand or for an alanine, PsbE/H23A, which cannot. In the other mutants, PsbE/Y19F and PsbE/T26P, the environment around PsbE/H23 was expected to be modified. From EPR, MALDI-TOF and O2 evolution activity measurements, the following results were obtained: Whereas the PsbE/H23M and PsbE/H23A mutants assemble only an apo-Cytb559 the steady-state level of active PSII was comparable to that in WT*3. The lack of the haem or, in PsbE/T26P, conversion of the high-potential into a lower potential form, slowed-down the recovery rate of the O2 activity after high-light illumination but did not affect the photoinhibition rate. This resulted in the following order for the steady-state level of active PSII centers under high-light conditions: PsbE/H23M≈PsbE/H23A<< PsbE/Y19F≤PsbE/T26P≤WT*3. These data show i) that the haem has no structural role provided that PsbE and PsbF are present, ii) a lack of correlation between the rate of photoinhibition and the Em of the haem and iii) that the holo-Cytb559 favors the recovery of a functional enzyme upon photoinhibition.
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Affiliation(s)
- Miwa Sugiura
- Proteo-Science Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan; Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan; PRESTO, Japan Science and Technology Agency (JST), 4-1-8, Honcho, Kawauchi, Saitama 332-0012, Japan.
| | - Makoto Nakamura
- Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Kazumi Koyama
- Proteo-Science Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Alain Boussac
- iBiTec-S, CNRS UMR 8221, CEA Saclay, 91191 Gif-sur-Yvette, France.
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The D1-173 amino acid is a structural determinant of the critical interaction between D1-Tyr161 (Tyr Z ) and D1-His190 in Photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1922-1931. [DOI: 10.1016/j.bbabio.2014.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 08/20/2014] [Accepted: 08/26/2014] [Indexed: 02/01/2023]
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Vinyard DJ, Gimpel J, Ananyev GM, Mayfield SP, Dismukes GC. Engineered Photosystem II reaction centers optimize photochemistry versus photoprotection at different solar intensities. J Am Chem Soc 2014; 136:4048-55. [PMID: 24548276 DOI: 10.1021/ja5002967] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The D1 protein of Photosystem II (PSII) provides most of the ligating amino acid residues for the Mn4CaO5 water-oxidizing complex (WOC) and half of the reaction center cofactors, and it is present as two isoforms in the cyanobacterium Synechococcus elongatus PCC 7942. These isoforms, D1:1 and D1:2, confer functional advantages for photosynthetic growth at low and high light intensities, respectively. D1:1, D1:2, and seven point mutations in the D1:2 background that are native to D1:1 were expressed in the green alga Chlamydomonas reinhardtii. We used these nine strains to show that those strains that confer a higher yield of PSII charge separation under light-limiting conditions (where charge recombination is significant) have less efficient photochemical turnover, measured in terms of both a lower WOC turnover probability and a longer WOC cycle period. Conversely, these same strains under light saturation (where charge recombination does not compete) confer a correspondingly faster O2 evolution rate and greater protection against photoinhibition. Taken together, the data clearly establish that PSII primary charge separation is a trade-off between photochemical productivity (water oxidation and plastoquinone reduction) and charge recombination (photoprotection). These trade-offs add up to a significant growth advantage for the two natural isoforms. These insights provide fundamental design principles for engineering of PSII reaction centers with optimal photochemical efficiencies for growth at low versus high light intensities.
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Affiliation(s)
- David J Vinyard
- Department of Chemistry and Chemical Biology and ‡Waksman Institute of Microbiology, Rutgers, The State University of New Jersey , Piscataway, New Jersey 08854, United States
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Sugiura M, Boussac A. Some Photosystem II properties depending on the D1 protein variants in Thermosynechococcus elongatus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1427-34. [PMID: 24388918 DOI: 10.1016/j.bbabio.2013.12.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 12/17/2013] [Accepted: 12/25/2013] [Indexed: 10/25/2022]
Abstract
Cyanobacteria have multiple psbA genes encoding PsbA, the D1 reaction center protein of the Photosystem II complex which bears together with PsbD, the D2 protein, most of the cofactors involved in electron transfer reactions. The thermophilic cyanobacterium Thermosynechococcus elongatus has three psbA genes differently expressed depending on the environmental conditions. Among the 344 residues constituting each of the 3 possible PsbA variants there are 21 substitutions between PsbA1 and PsbA3, 31 between PsbA1 and PsbA2 and 27 between PsbA2 and PsbA3. In this review, we summarize the changes already identified in the properties of the redox cofactors depending on the D1 variant constituting Photosystem II in T. elongatus. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.
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Affiliation(s)
- Miwa Sugiura
- Proteo-science Research Center, Ehime University, Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan; PRESTO, Japan Science and Technology Agency (JST), 4-1-8, Honcho, Kawauchi, Saitama 332-0012, Japan.
| | - Alain Boussac
- iBiTec-S, CNRS UMR 8221, CEA Saclay, 91191 Gif-sur-Yvette, France.
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