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  • 1.
    Benlloch, Reyes
    et al.
    Department of Forest Genetics and Plant Physiology, SLU.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hainzl, Tobias
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Grundström, Christin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shutova, Tatyana
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Samuelsson, Göran
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Sauer-Eriksson, Elisabeth
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Crystal structure and functional characterization of Photosystem II-associated carbonic anhydrase CAH3 in Chlamydomonas reinhardtii2015In: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 167, no 3, p. 950-962Article in journal (Refereed)
    Abstract [en]

    In oxygenic photosynthesis, light energy is stored in the form of chemical energy by converting CO2 and water into carbohydrates.The light-driven oxidation of water that provides the electrons and protons for the subsequent CO2 fixation takes place inphotosystem II (PSII). Recent studies show that in higher plants, HCO3– increases PSII activity by acting as a mobile acceptor ofthe protons produced by PSII. In the green alga Chlamydomonas reinhardtii, a luminal carbonic anhydrase, CrCAH3, was suggested toimprove proton removal from PSII, possibly by rapid reformation of HCO3– from CO2. In this study, we investigated the interplaybetween PSII and CrCAH3 by membrane inlet mass spectrometry and x-ray crystallography. Membrane inlet mass spectrometrymeasurements showed that CrCAH3 was most active at the slightly acidic pH values prevalent in the thylakoid lumen underillumination. Two crystal structures of CrCAH3 in complex with either acetazolamide or phosphate ions were determined at 2.6- and2.7-Å resolution, respectively. CrCAH3 is a dimer at pH 4.1 that is stabilized by swapping of the N-terminal arms, a feature notpreviously observed in a-type carbonic anhydrases. The structure contains a disulfide bond, and redox titration of CrCAH3 functionwith dithiothreitol suggested a possible redox regulation of the enzyme. The stimulating effect of CrCAH3 and CO2/HCO3– on PSIIactivity was demonstrated by comparing the flash-induced oxygen evolution pattern of wild-type and CrCAH3-less PSIIpreparations. We showed that CrCAH3 has unique structural features that allow this enzyme to maximize PSII activity at lowpH and CO2 concentration.

  • 2. Bryan, Samantha J.
    et al.
    Burroughs, Nigel J.
    Shevela, Dmitriy
    Department of Mathematics and Natural Science, University of Stavanger, Stavanger, Norway.
    Yu, Jianfeng
    Rupprecht, Eva
    Liu, Lu-Ning
    Mastroianni, Giulia
    Xue, Quan
    Llorente-Garcia, Isabel
    Leake, Mark C.
    Eichacker, Lutz A.
    Schneider, Dirk
    Nixon, Peter J.
    Mullineaux, Conrad W.
    Localisation and interaction of the Vipp1 protein in cyanobacteria2014In: Molecular Microbiology, ISSN 0950-382X, E-ISSN 1365-2958, Vol. 94, p. 1179-1195Article in journal (Refereed)
    Abstract [en]

    The Vipp1 protein is essential in cyanobacteria and chloroplasts for the maintenance of photosynthetic function and thylakoid membrane architecture. To investigate its mode of action we generated strains of the cyanobacteria Synechocystis sp. PCC6803 and Synechococcus sp. PCC7942 in which Vipp1 was tagged with green fluorescent protein at the C-terminus and expressed from the native chromosomal locus. There was little perturbation of function. Live-cell fluorescence imaging shows dramatic relocalisation of Vipp1 under high light. Under low light, Vipp1 is predominantly dispersed in the cytoplasm with occasional concentrations at the outer periphery of the thylakoid membranes. High light induces Vipp1 coalescence into localised puncta within minutes, with net relocation of Vipp1 to the vicinity of the cytoplasmic membrane and the thylakoid membranes. Pull-downs and mass spectrometry identify an extensive collection of proteins that are directly or indirectly associated with Vipp1 only after high-light exposure. These include not only photosynthetic and stress-related proteins but also RNA-processing, translation and protein assembly factors. This suggests that the Vipp1 puncta could be involved in protein assembly. One possibility is that Vipp1 is involved in the formation of stress-induced localised protein assembly centres, enabling enhanced protein synthesis and delivery to membranes under stress conditions.

  • 3.
    Burén, Stefan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Ortega-Villasante, Cristina
    Blanco-Rivero, Amaya
    Martínez-Bernardini, Andrea
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Shutova, Tatiana
    Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC). Umeå University, Faculty of Science and Technology, Department of Plant Physiology.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Bako, Laszlo
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Villarejo, Arsenio
    Samuelsson, Göran
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Importance of post-translational modifications for functionality of a chloroplast-localized carbonic anhydrase (CAH1) in Arabidopsis thaliana2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 6, p. e21021-Article in journal (Refereed)
    Abstract [en]

    Background

    The Arabidopsis CAH1 alpha-type carbonic anhydrase is one of the few plant proteins known to be targeted to the chloroplast through the secretory pathway. CAH1 is post-translationally modified at several residues by the attachment of N-glycans, resulting in a mature protein harbouring complex-type glycans. The reason of why trafficking through this non-canonical pathway is beneficial for certain chloroplast resident proteins is not yet known. Therefore, to elucidate the significance of glycosylation in trafficking and the effect of glycosylation on the stability and function of the protein, epitope-labelled wild type and mutated versions of CAH1 were expressed in plant cells.

    Methodology/Principal Findings

    Transient expression of mutant CAH1 with disrupted glycosylation sites showed that the protein harbours four, or in certain cases five, N-glycans. While the wild type protein trafficked through the secretory pathway to the chloroplast, the non-glycosylated protein formed aggregates and associated with the ER chaperone BiP, indicating that glycosylation of CAH1 facilitates folding and ER-export. Using cysteine mutants we also assessed the role of disulphide bridge formation in the folding and stability of CAH1. We found that a disulphide bridge between cysteines at positions 27 and 191 in the mature protein was required for correct folding of the protein. Using a mass spectrometric approach we were able to measure the enzymatic activity of CAH1 protein. Under circumstances where protein N-glycosylation is blocked in vivo, the activity of CAH1 is completely inhibited.

    Conclusions/Significance

    We show for the first time the importance of post-translational modifications such as N-glycosylation and intramolecular disulphide bridge formation in folding and trafficking of a protein from the secretory pathway to the chloroplast in higher plants. Requirements for these post-translational modifications for a fully functional native protein explain the need for an alternative route to the chloroplast.

  • 4. Christianson, Helena C.
    et al.
    Menard, Julien A.
    Chandran, Vineesh Indira
    Bourseau-Guilmain, Erika
    Shevela, Dmitry
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Lidfeldt, Jon
    Mansson, Ann-Sofie
    Pastorekova, Silvia
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Skane Univ Hosp, Lund, Sweden.
    Belting, Mattias
    Tumor antigen glycosaminoglycan modification regulates antibody-drug conjugate delivery and cytotoxicity2017In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 8, no 40, p. 66960-66974Article in journal (Refereed)
    Abstract [en]

    Aggressive cancers are characterized by hypoxia, which is a key driver of tumor development and treatment resistance. Proteins specifically expressed in the hypoxic tumor microenvironment thus represent interesting candidates for targeted drug delivery strategies. Carbonic anhydrase (CAIX) has been identified as an attractive treatment target as it is highly hypoxia specific and expressed at the cell-surface to promote cancer cell aggressiveness. Here, we find that cancer cell internalization of CAIX is negatively regulated by post-translational modification with chondroitin or heparan sulfate glycosaminoglycan chains. We show that perturbed glycosaminoglycan modification results in increased CAIX endocytosis. We hypothesized that perturbation of CAIX glycosaminoglycan conjugation may provide opportunities for enhanced drug delivery to hypoxic tumor cells. In support of this concept, pharmacological inhibition of glycosaminoglycan biosynthesis with xylosides significantly potentiated the internalization and cytotoxic activity of an antibody-drug conjugate (ADC) targeted at CAIX. Moreover, cells expressing glycosaminoglycan-deficient CAIX were significantly more sensitive to ADC treatment as compared with cells expressing wild-type CAIX. We find that inhibition of CAIX endocytosis is associated with an increased localization of glycosaminoglycan-conjugated CAIX in membrane lipid raft domains stabilized by caveolin-1 clusters. The association of CAIX with caveolin-1 was partially attenuated by acidosis, i.e. another important feature of malignant tumors. Accordingly, we found increased internalization of CAIX at acidic conditions. These findings provide first evidence that intracellular drug delivery at pathophysiological conditions of malignant tumors can be attenuated by tumor antigen glycosaminoglycan modification, which is of conceptual importance in the future development of targeted cancer treatments.

  • 5. Govindjee,
    et al.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Björn, Lars Olof
    Evolution of the Z-scheme of photosynthesis: a perspective2017In: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 133, no 1-3, p. 5-15Article in journal (Refereed)
    Abstract [en]

    The concept of the Z-scheme of oxygenic photosynthesis is in all the textbooks. However, its evolution is not. We focus here mainly on some of the history of its biophysical aspects. We have arbitrarily divided here the 1941-2016 period into three sub-periods: (a) Origin of the concept of two light reactions: first hinted at, in 1941, by James Franck and Karl Herzfeld; described and explained, in 1945, by Eugene Rabinowitch; and a clear hypothesis, given in 1956 by Rabinowitch, of the then available cytochrome experiments: one light oxidizing it and another reducing it; (b) Experimental discovery of the two light reactions and two pigment systems and the Z-scheme of photosynthesis: Robert Emerson's discovery, in 1957, of enhancement in photosynthesis when two light beams (one in the far-red region, and the other of shorter wavelengths) are given together than when given separately; and the 1960 scheme of Robin Hill & Fay Bendall; and (c) Evolution of the many versions of the Z-Scheme: Louis Duysens and Jan Amesz's 1961 experiments on oxidation and reduction of cytochrome f by two different wavelengths of light, followed by the work of many others for more than 50 years.

  • 6. Kern, Jan
    et al.
    Chatterjee, Ruchira
    Young, Iris D.
    Fuller, Franklin D.
    Lassalle, Louise
    Ibrahim, Mohamed
    Gul, Sheraz
    Fransson, Thomas
    Brewster, Aaron S.
    Alonso-Mori, Roberto
    Hussein, Rana
    Zhang, Miao
    Douthit, Lacey
    de Lichtenberg, Casper
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Chemistry—Ångström, Molecular Biomimetics, Uppsala University, Uppsala, Sweden.
    Cheah, Mun Hon
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Wersig, Julia
    Seuffert, Ina
    Sokaras, Dimosthenis
    Pastor, Ernest
    Weninger, Clemens
    Kroll, Thomas
    Sierra, Raymond G.
    Aller, Pierre
    Butryn, Agata
    Orville, Allen M.
    Liang, Mengning
    Batyuk, Alexander
    Koglin, Jason E.
    Carbajo, Sergio
    Boutet, Sébastien
    Moriarty, Nigel W.
    Holton, James M.
    Dobbek, Holger
    Adams, Paul D.
    Bergmann, Uwe
    Sauter, Nicholas K.
    Zouni, Athina
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Yano, Junko
    Yachandra, Vittal K.
    Structures of the intermediates of Kok’s photosynthetic water oxidation clock2018In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 563, p. 421-425Article in journal (Refereed)
    Abstract [en]

    Inspired by the period-four oscillation in flash-induced oxygen evolution of photosystem II discovered by Joliot in 1969, Kok performed additional experiments and proposed a five-state kinetic model for photosynthetic oxygen evolution, known as Kok’s S-state clock or cycle1,2. The model comprises four (meta)stable intermediates (S0, S1, S2 and S3) and one transient S4 state, which precedes dioxygen formation occurring in a concerted reaction from two water-derived oxygens bound at an oxo-bridged tetra manganese calcium (Mn4CaO5) cluster in the oxygen-evolving complex3–7. This reaction is coupled to the two-step reduction and protonation of the mobile plastoquinone QB at the acceptor side of PSII. Here, using serial femtosecond X-ray crystallography and simultaneous X-ray emission spectroscopy with multi-flash visible laser excitation at room temperature, we visualize all (meta)stable states of Kok’s cycle as high-resolution structures (2.04–2.08 Å). In addition, we report structures of two transient states at 150 and 400 µs, revealing notable structural changes including the binding of one additional ‘water’, Ox, during the S2→S3 state transition. Our results suggest that one water ligand to calcium (W3) is directly involved in substrate delivery. The binding of the additional oxygen Ox in the S3 state between Ca and Mn1 supports O–O bond formation mechanisms involving O5 as one substrate, where Ox is either the other substrate oxygen or is perfectly positioned to refill the O5 position during O2 release. Thus, our results exclude peroxo-bond formation in the S3 state, and the nucleophilic attack of W3 onto W2 is unlikely.

  • 7.
    Koroidov, Sergey
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shutova, Tatyana
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Mobile hydrogen carbonate acts as proton acceptor in photosynthetic water oxidation2014In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 11, no 17, p. 6299-6304Article in journal (Refereed)
    Abstract [en]

    Cyanobacteria, algae and plants oxidize water to the O2 we breathe, and consume CO2 during the synthesis of biomass. Although these vital processes are functionally and structurally well separated in photosynthetic organisms, there is a long-debated role for CO2/HCO3 in water oxidation. Using membrane-inlet mass spectrometry we demonstrate that HCO3 acts as a mobile proton acceptor that helps to transport the protons produced inside of photosystem II by water-oxidation out into the chloroplast's lumen, resulting in a light-driven production of O2 and CO2. Depletion of HCO3 from the media leads, in the absence of added buffers, to a reversible down-regulation of O2 production by about 20%. These findings add a previously unidentified component to the regulatory network of oxygenic photosynthesis, and conclude the more than 50-y-long quest for the function of CO2/ HCO3 in photosynthetic water oxidation.

  • 8. Melder, Jens
    et al.
    Kwong, Wai Ling
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Molecular Biomimetics, Department of Chemistry, Ångström Laboratory, Uppsala Universitet.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Molecular Biomimetics, Department of Chemistry, Ångström Laboratory, Uppsala Universitet.
    Kurz, Philipp
    Electrocatalytic Water Oxidation by MnOx/C: In Situ Catalyst Formation, Carbon Substrate Variations, and Direct O2/CO2 Monitoring by Membrane-Inlet Mass Spectrometry2017In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 10, no 22, p. 4491-4502Article in journal (Refereed)
    Abstract [en]

    Layers of amorphous manganese oxides were directly formed on the surfaces of different carbon materials by exposing the carbon to aqueous solutions of permanganate (MnO4- ) followed by sintering at 100-400 °C. During electrochemical measurements in neutral aqueous buffer, nearly all of the MnOx /C electrodes show significant oxidation currents at potentials relevant for the oxygen evolution reaction (OER). However, by combining electrolysis with product detection by using mass spectrometry, it was found that these currents were only strictly linked to water oxidation if MnOx was deposited on graphitic carbon materials (faradaic O2 yields >90 %). On the contrary, supports containing sp3 -C were found to be unsuitable as the OER is accompanied by carbon corrosion to CO2 . Thus, choosing the "right" carbon material is crucial for the preparation of stable and efficient MnOx /C anodes for water oxidation catalysis. For MnOx on graphitic substrates, current densities of >1 mA cm-2 at η=540 mV could be maintained for at least 16 h of continuous operation at pH 7 (very good values for electrodes containing only abundant elements such as C, O, and Mn) and post-operando measurements proved the integrity of both the catalyst coating and the underlying carbon at OER conditions.

  • 9.
    Messinger, Johannes
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Principles of photosynthesis2012In: Fundamentals of materials for energy and environmental sustainability / [ed] David S. Ginley and David Cahen, Cambridge University Press, 2012, p. 302-314Chapter in book (Refereed)
  • 10. Mork-Jansson, Astrid Elisabeth
    et al.
    Gargano, Daniela
    Kmiec, Karol
    Fumes, Clemens
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Center for Organelle Research, University of Stavanger, Stavanger, Norway.
    Eichacker, Lutz Andreas
    Lil3 dimerization and chlorophyll binding in Arabidopsis thaliana2015In: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 589, no 20, p. 3064-3070Article in journal (Refereed)
    Abstract [en]

    The two-helix light harvesting like (Lil) protein Lil3 belongs to the family of chlorophyll binding light harvesting proteins of photosynthetic membranes. A function in tetrapyrrol synthesis and stabilization of geranylgeraniol reductase has been shown. Lil proteins contain the chlorophyll a/b-binding motif; however, binding of chlorophyll has not been demonstrated. We find that Lil3.2 from Arabidopsis thaliana forms heterodimers with Lil3.1 and binds chlorophyll. Lil3.2 heterodimerization (25 +/- 7.8 nM) is favored relative to homodimerization (431 +/- 59 nM). Interaction of Lil3.2 with chlorophyll a (231 +/- 49 nM) suggests that heterodimerization precedes binding of chlorophyll in Arabidopsis thatiana. 

  • 11. Nöring, Birgit
    et al.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Renger, Gernot
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Effects of methanol on the S( i )-state transitions in photosynthetic water-splitting.2008In: Photosynthesis Research, ISSN 0166-8595, Vol. 98, no 1-3, p. 251-60Article in journal (Refereed)
    Abstract [en]

    From a chemical point of view methanol is one of the closest analogues of water. Consistent with this idea EPR spectroscopy studies have shown that methanol binds at—or at least very close to—the Mn4O x Ca cluster of photosystem II (PSII). In contrast, Clark-type oxygen rate measurements demonstrate that the O2 evolving activity of PSII is surprisingly unaffected by methanol concentrations of up to 10%. Here we study for the first time in detail the effect of methanol on photosynthetic water-splitting by employing a Joliot-type bare platinum electrode. We demonstrate a linear dependence of the miss parameter for S i state advancement on the methanol concentrations in the range of 0–10% (v/v). This finding is consistent with the idea that methanol binds in PSII with similar affinity as water to one or both substrate binding sites at the Mn4O x Ca cluster. The possibility is discussed that the two substrate water molecules bind at different stages of the cycle, one during the S4 → S0 and the other during the S2 → S3 transition.

  • 12.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ananyev, Gennady
    Vatland, Ann K.
    Arnold, Janine
    Mamedov, Fikret
    Eichacker, Lutz A.
    Dismukes, G. Charles
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    'Birth defects' of photosystem II make it highly susceptible to photodamage during chloroplast biogenesis2019In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 166, no 1, p. 165-180Article in journal (Refereed)
    Abstract [en]

    High solar flux is known to diminish photosynthetic growth rates, reducing biomass productivity and lowering disease tolerance. Photosystem II (PSII) of plants is susceptible to photodamage (also known as photoinactivation) in strong light, resulting in severe loss of water oxidation capacity and destruction of the water‐oxidizing complex (WOC). The repair of damaged PSIIs comes at a high energy cost and requires de novo biosynthesis of damaged PSII subunits, reassembly of the WOC inorganic cofactors and membrane remodeling. Employing membrane‐inlet mass spectrometry and O2‐polarography under flashing light conditions, we demonstrate that newly synthesized PSII complexes are far more susceptible to photodamage than are mature PSII complexes. We examined these ‘PSII birth defects’ in barley seedlings and plastids (etiochloroplasts and chloroplasts) isolated at various times during de‐etiolation as chloroplast development begins and matures in synchronization with thylakoid membrane biogenesis and grana membrane formation. We show that the degree of PSII photodamage decreases simultaneously with biogenesis of the PSII turnover efficiency measured by O2‐polarography, and with grana membrane stacking, as determined by electron microscopy. Our data from fluorescence, QB‐inhibitor binding, and thermoluminescence studies indicate that the decline of the high‐light susceptibility of PSII to photodamage is coincident with appearance of electron transfer capability QA− → QB during de‐etiolation. This rate depends in turn on the downstream clearing of electrons upon buildup of the complete linear electron transfer chain and the formation of stacked grana membranes capable of longer‐range energy transfer.

  • 13.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Centre for Organelle Research, Faculty of Science and Technology, University of Stavanger, Stavanger, Norway.
    Arnold, Janine
    Reisinger, Veronika
    Berends, Hans-Martin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kmiec, Karol
    Koroidov, Sergey
    Umeå University, Faculty of Science and Technology, Department of Chemistry. PULSE Institute, SLAC National Accelerator Laboratory, Stanford University, Stanford, CA, USA.
    Bue, Ann Kristin
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Eichacker, Lutz A.
    Biogenesis of water splitting by photosystem II during de-etiolation of barley (Hordeum vulgare L.)2016In: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 39, no 7, p. 1524-1536Article in journal (Refereed)
    Abstract [en]

    Etioplasts lack thylakoid membranes and photosystem complexes. Light triggers differentiation of etioplasts into mature chloroplasts, and photosystem complexes assemble in parallel with thylakoid membrane development. Plastids isolated at various time points of de-etiolation are ideal to study the kinetic biogenesis of photosystem complexes during chloroplast development. Here, we investigated the chronology of photosystem II (PSII) biogenesis by monitoring assembly status of chlorophyll-binding protein complexes and development of water splitting via O2 production in plastids (etiochloroplasts) isolated during de-etiolation of barley (Hordeum vulgare L.). Assembly of PSII monomers, dimers and complexes binding outer light-harvesting antenna [PSII-light-harvesting complex II (LHCII) supercomplexes] was identified after 1, 2 and 4 h of de-etiolation, respectively. Water splitting was detected in parallel with assembly of PSII monomers, and its development correlated with an increase of bound Mn in the samples. After 4 h of de-etiolation, etiochloroplasts revealed the same water-splitting efficiency as mature chloroplasts. We conclude that the capability of PSII to split water during de-etiolation precedes assembly of the PSII-LHCII supercomplexes. Taken together, data show a rapid establishment of water-splitting activity during etioplast-to-chloroplast transition and emphasize that assembly of the functional water-splitting site of PSII is not the rate-limiting step in the formation of photoactive thylakoid membranes.

  • 14.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Beckmann, Katrin
    Clausen, Jürgen
    Junge, Wolfgang
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Membrane-inlet mass spectrometry reveals a high driving force for oxygen production by photosystem II2011In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 108, no 9, p. 3602-3607Article in journal (Refereed)
    Abstract [en]

    Oxygenic photosynthesis is the basis for aerobic life on earth. The catalytic Mn(4)O(x)CaY(Z) center of photosystem II (PSII), after fourfold oxidation, extracts four electrons from two water molecules to yield dioxygen. This reaction cascade has appeared as a single four-electron transfer that occurs in typically 1 ms. Inevitable redox intermediates have so far escaped detection, probably because of very short lifetime. Previous attempts to stabilize intermediates by high O(2)-back pressure have revealed controversial results. Here we monitored by membrane-inlet mass spectrometry (MIMS) the production of from (18)O-labeled water against a high background of in a suspension of PSII-core complexes. We found neither an inhibition nor an altered pattern of O(2) production by up to 50-fold increased concentration of dissolved O(2). Lack of inhibition is in line with results from previous X-ray absorption and visible-fluorescence experiments, but contradictory to the interpretation of previous UV-absorption data. Because we used essentially identical experimental conditions in MIMS as had been used in the UV work, the contradiction was serious, and we found it was not to be resolved by assuming a significant slowdown of the O(2) release kinetics or a subsequent slow conformational relaxation. This calls for reevaluation of the less direct UV experiments. The direct detection of O(2) release by MIMS shows unequivocally that O(2) release in PSII is highly exothermic. Under the likely assumption that one H(+) is released in the S(4) → S(0) transition, the driving force at pH 6.5 and atmospheric O(2) pressure is at least 220 meV, otherwise 160 meV.

  • 15.
    Shevela, Dmitriy
    et al.
    Centre for Organelle Research, Department of Mathematics and Natural Science, University of Stavanger, Stavanger, Norway.
    Björn, Lars Olof
    Govindjee, -
    Oxygenic photosynthesis2013In: Natural and artificial photosynthesis: solar power as an energy source / [ed] Reza Razeghifard, Hoboken, New Jersey: John Wiley & Sons, 2013, p. 13-63Chapter in book (Refereed)
    Abstract [en]

    This chapter is intended as a background on natural photosynthesis for those interested in artificial photosynthesis. It describes how light is used for creating positive and negative charges, and how these charges are transferred through the molecular assemblies in the membranes. Next, the chapter also describes how the charge transport leads to creation of a pH difference across the photosynthetic membrane, and how charge and pH differences lead to the production of high-energy phosphate that can be used in chemical synthesis. The chapter overviews photophosphorylation in chromatophores of photosynthetic bacteria and, discusses carbon dioxide assimilation systems in oxygenic organisms. Finally, it describes how the type of photosynthesis present today has evolved over billions of years, and what can we expect of the future that we are ourselves able to influence. In addition, in the end, the chapter considers some interesting photosynthesis-related questions relevant to whole land and aquatic plants.

  • 16.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Björn, Lars Olof
    Lund University, Sweden.
    Govindjee,
    University of Illinois at Urbana-Champaign, USA.
    Photosynthesis: solar energy for life2018Book (Other academic)
    Abstract [en]

    Photosynthesis has been an important field of research for more than a century, but the present concerns about energy, environment and climate have greatly intensified interest in and research on this topic. Research has progressed rapidly in recent years, and this book is an interesting read for an audience who is concerned with various ways of harnessing solar energy.

    Our understanding of photosynthesis can now be said to have reached encyclopedic dimensions. There have been, in the past, many good books at various levels. Our book is expected to fulfill the needs of advanced undergraduate and beginning graduate students in branches of biology, biochemistry, biophysics, and bioengineering because photosynthesis is the basis of future advances in producing more food, more biomass, more fuel, and new chemicals for our expanding global human population. Further, the basics of photosynthesis are and will be used not only for the above, but in artificial photosynthesis, an important emerging field where chemists, researchers and engineers of solar energy systems will play a major role.

  • 17.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Koroidov, Sergey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Najafpour, M Mahdi
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kurz, Philipp
    Calcium manganese oxides as oxygen evolution catalysts: o(2) formation pathways indicated by (18) o-labelling studies2011In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, no 19, p. 5415-5423Article in journal (Refereed)
    Abstract [en]

    Oxygen evolution catalysed by calcium manganese and manganese-only oxides was studied in (18) O-enriched water. Using membrane-inlet mass spectrometry, we monitored the formation of the different O(2) isotopologues (16) O(2) , (16) O(18) O and (18) O(2) in such reactions simultaneously with good time resolution. From the analysis of the data, we conclude that entirely different pathways of dioxygen formation catalysis exist for reactions involving hydrogen peroxide (H(2) O(2) ), hydrogen persulfate (HSO(5) (-) ) or single-electron oxidants such as Ce(IV) and [Ru(III) (bipy)(3) ](3+) . Like the studied oxide catalysts, the active sites of manganese catalase and the oxygen-evolving complex (OEC) of photosystem II (PSII) consist of μ-oxido manganese or μ-oxido calcium manganese sites. The studied processes show very similar (18) O-labelling behaviour to the natural enzymes and are therefore interesting model systems for in vivo oxygen formation by manganese metalloenzymes such as PSII.

  • 18.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Probing the turnover efficiency of photosystem II membrane fragments with different electron acceptors2012In: Biochimica et Biophysica Acta, ISSN 0006-3002, E-ISSN 1878-2434, Vol. 1817, no 8, p. 1208-1212Article in journal (Refereed)
    Abstract [en]

    In this study we employ isotope ratio membrane-inlet mass spectrometry to probe the turnover efficiency of photosystem II (PSII) membrane fragments isolated from spinach at flash frequencies between 1Hz and 50Hz in the presence of the commonly used exogenous electron acceptors potassium ferricyanide(III) (FeCy), 2,5-dichloro-p-benzoquinone (DCBQ), and 2-phenyl-p-benzoquinone (PPBQ). The data obtained clearly indicate that among the tested acceptors PPBQ is the best at high flash frequencies. If present at high enough concentration, the PSII turnover efficiency is unaffected by flash frequency of up to 30Hz, and at 40Hz and 50Hz only a slight decrease by about 5-7% is observed. In contrast, drastic reductions of the O(2) yields by about 40% and 65% were found at 50Hz for DCBQ and FeCy, respectively. Comparison with literature data reveals that PPBQ accepts electrons from Q(A)(-) in PSII membrane fragments with similar efficiency as plastoquinone in intact cells. Our data also confirm that at high flashing rates O(2) evolution is limited by the reactions on the electron-acceptor side of PSII. The relevance of these data to the evolutionary development of the water-splitting complex in PSII and with regard to the potential of artificial water-splitting catalysts is discussed. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial Photosynthesis.

  • 19.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Studying the oxidation of water to molecular oxygen in photosynthetic and artificial systems by time-resolved membrane-inlet mass spectrometry2013In: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 473, no 4, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Monitoring isotopic compositions of gaseous products (e.g., H2, O2, and CO2) by time-resolved isotope-ratio membrane-inlet mass spectrometry (TR-IR-MIMS) is widely used for kinetic and functional analyses in photosynthesis research. In particular, in combination with isotopic labeling, TR-MIMS became an essential and powerful research tool for the study of the mechanism of photosynthetic water-oxidation to molecular oxygen catalyzed by the water-oxidizing complex of photosystem II. Moreover, recently, the TR-MIMS and 18O-labeling approach was successfully applied for testing newly developed catalysts for artificial water-splitting and provided important insight about the mechanism and pathways of O2 formation. In this mini-review we summarize these results and provide a brief introduction into key aspects of the TR-MIMS technique and its perspectives for future studies of the enigmatic water-splitting chemistry.

  • 20.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ort, Donald R.
    Department of Plant Biology, University of Illinois, Urbana, IL, 61801, USA .
    Book Review: Agu Laisk, Ladislav Nedbal, and Govindjee (eds): Photosynthesis in silico. Understanding complexity from molecules to ecosystems.2010In: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 103, no 2, p. 139-140Article, book review (Refereed)
  • 21.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Nöring, Birgit
    Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Koroidov, Sergey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shutova, Tatyana
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Efficiency of photosynthetic water oxidation at ambient and depleted levels of inorganic carbon2013In: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 117, no 1-3, p. 401-412Article in journal (Refereed)
    Abstract [en]

    Over 40 years ago, Joliot et al. (Photochem Photobiol 10:309-329, 1969) designed and employed an elegant and highly sensitive electrochemical technique capable of measuring O2 evolved by photosystem II (PSII) in response to trains of single turn-over light flashes. The measurement and analysis of flash-induced oxygen evolution patterns (FIOPs) has since proven to be a powerful method for probing the turnover efficiency of PSII. Stemler et al. (Proc Natl Acad Sci USA 71(12):4679-4683, 1974), in Govindjee's lab, were the first to study the effect of "bicarbonate" on FIOPs by adding the competitive inhibitor acetate. Here, we extend this earlier work by performing FIOPs experiments at various, strictly controlled inorganic carbon (Ci) levels without addition of any inhibitors. For this, we placed a Joliot-type bare platinum electrode inside a N2-filled glove-box (containing 10-20 ppm CO2) and reduced the Ci concentration simply by washing the samples in Ci-depleted media. FIOPs of spinach thylakoids were recorded either at 20-times reduced levels of Ci or at ambient Ci conditions (390 ppm CO2). Numerical analysis of the FIOPs within an extended Kok model reveals that under Ci-depleted conditions the miss probability is discernibly larger (by 2-3 %) than at ambient conditions, and that the addition of 5 mM HCO3 (-) to the Ci-depleted thylakoids largely restores the original miss parameter. Since a "mild" Ci-depletion procedure was employed, we discuss our data with respect to a possible function of free or weakly bound HCO3 (-) at the water-splitting side of PSII.

  • 22.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Mathematics and Natural Science, Centre for Organelle Research, University of Stavanger, Stavanger, Norway.
    Pishchalnikov, Roman Y.
    Eichacker, Lutz A.
    Govindjee, .
    Oxygenic photosynthesis in cyanobacteria2013In: Stress biology of cyanobacteria: molecular mechanisms to cellular responses / [ed] Ashish Kumar Srivastava, Amar Nath Rai, Brett A. Neilan, Boca Raton, FL: CRC Press, 2013, 1, p. 3-40Chapter in book (Refereed)
  • 23.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Schröder, Wolfgang P.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Chemistry - Ångström Laboratory, Uppsala University, UppsalaSweden.
    Liquid-phase measurements of photosynthetic oxygen evolution2018In: Methods in Molecular Biology, ISSN 1064-3745, E-ISSN 1940-6029, Vol. 1770, p. 197-211Article in journal (Refereed)
    Abstract [en]

    This chapter compares two different techniques for monitoring photosynthetic O2 production: the widespread Clark-type O2 electrode and the more sophisticated membrane inlet mass spectrometry (MIMS) technique. We describe how a simple membrane inlet for MIMS can be made out of a commercial Clark-type cell, and outline the advantages and drawbacks of the two techniques to guide researchers in deciding which method to use. Protocols and examples are given for measuring O2 evolution rates and for determining the number of chlorophyll molecules per active photosystem II reaction center.

  • 24.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Su, Ji-Hu
    Klimov, Vyacheslav
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hydrogencarbonate is not a tightly bound constituent of the water-oxidizing complex in photosystem II2008In: Biochimica et Biophysica Acta (BBA) - Bioenergetics, Vol. 1777, no 6, p. 532-9Article in journal (Refereed)
    Abstract [en]

    Since the end of the 1950s hydrogencarbonate (‘bicarbonate') is discussed as a possible cofactor of photosynthetic water-splitting, and in a recent X-ray crystallography model of photosystem II (PSII) it was displayed as a ligand of the Mn4OxCa cluster. Employing membrane-inlet mass spectrometry (MIMS) and isotope labelling we confirm the release of less than one (≈ 0.3) HCO3- per PSII upon addition of formate. The same amount of HCO3- release is observed upon formate addition to Mn-depleted PSII samples. This suggests that formate does not replace HCO3- from the donor side, but only from the non-heme iron at the acceptor side of PSII. The absence of a firmly bound HCO3- is corroborated by showing that a reductive destruction of the Mn4OxCa cluster inside the MIMS cell by NH2OH addition does not lead to any CO2/HCO3- release. We note that even after an essentially complete HCO3-/CO2 removal from the sample medium by extensive degassing in the MIMS cell the PSII samples retain ≥ 75% of their initial flash-induced O2-evolving capacity. We therefore conclude that HCO3- has only ‘indirect' effects on water-splitting in PSII, possibly by being part of a proton relay network and/or by participating in assembly and stabilization of the water-oxidizing complex.

  • 25. Tikhonov, K.
    et al.
    Shevela, Dmitry
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Klimov, V. V.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Chemistry, Molecular Biomimetics, Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Quantification of bound bicarbonate in photosystem II2018In: Photosynthetica (Praha), ISSN 0300-3604, E-ISSN 1573-9058, Vol. 56, no 1, p. 210-216Article in journal (Refereed)
    Abstract [en]

    In this study, we presented a new approach for quantification of bicarbonate (HCO3-) molecules bound to PSII. Our method, which is based on a combination of membrane-inlet mass spectrometry (MIMS) and O-18-labelling, excludes the possibility of "non-accounted" HCO3- by avoiding (1) the employment of formate for removal of HCO3- from PSII, and (2) the extremely low concentrations of HCO3-/CO2 during online MIMS measurements. By equilibration of PSII sample to ambient CO2 concentration of dissolved CO2/HCO3-, the method ensures that all physiological binding sites are saturated before analysis. With this approach, we determined that in spinach PSII membrane fragments 1.1 +/- 0.1 HCO3- are bound per PSII reaction center, while none was bound to isolated PsbO protein. Our present results confirmed that PSII binds one HCO3- molecule as ligand to the non-heme iron of PSII, while unbound HCO3- optimizes the water-splitting reactions by acting as a mobile proton shuttle.

  • 26. Young, Iris D.
    et al.
    Ibrahim, Mohamed
    Chatterjee, Ruchira
    Gul, Sheraz
    Fuller, Franklin D.
    Koroidov, Sergey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Brewster, Aaron S.
    Tran, Rosalie
    Alonso-Mori, Roberto
    Kroll, Thomas
    Michels-Clark, Tara
    Laksmono, Hartawan
    Sierra, Raymond G.
    Stan, Claudiu A.
    Hussein, Rana
    Zhang, Miao
    Douthit, Lacey
    Kubin, Markus
    de Lichtenberg, Casper
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Vo Pham, Long
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Nilsson, Håkan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Cheah, Mun Hon
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shevela, Dmitriy
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Saracini, Claudio
    Bean, Mackenzie A.
    Seuffert, Ina
    Sokaras, Dimosthenis
    Weng, Tsu-Chien
    Pastor, Ernest
    Weninger, Clemens
    Fransson, Thomas
    Lassalle, Louise
    Bräuer, Philipp
    Aller, Pierre
    Docker, Peter T.
    Andi, Babak
    Orville, Allen M.
    Glownia, James M.
    Nelson, Silke
    Sikorski, Marcin
    Zhu, Diling
    Hunter, Mark S.
    Lane, Thomas J.
    Aquila, Andy
    Koglin, Jason E.
    Robinson, Joseph
    Liang, Mengning
    Boutet, Sébastien
    Lyubimov, Artem Y.
    Uervirojnangkoorn, Monarin
    Moriarty, Nigel W.
    Liebschner, Dorothee
    Afonine, Pavel V.
    Waterman, David G.
    Evans, Gwyndaf
    Wernet, Philippe
    Dobbek, Holger
    Weis, William I.
    Brunger, Axel T.
    Zwart, Petrus H.
    Adams, Paul D.
    Zouni, Athina
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Chemistry, Molecular Biomimetics, Ångström Laboratory, Uppsala University.
    Bergmann, Uwe
    Sauter, Nicholas K.
    Kern, Jan
    Yachandra, Vittal K.
    Yano, Junko
    Structure of photosystem II and substrate binding at room temperature2016In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 540, no 7633, p. 453-457Article in journal (Refereed)
    Abstract [en]

    Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment protein complex, couples the one-electron photochemistry at the reaction centre with the four-electron redox chemistry of water oxidation at the Mn4CaO5 cluster in the oxygen-evolving complex (OEC). Under illumination, the OEC cycles through five intermediate S-states (S0 to S4)1, in which S1 is the dark-stable state and S3 is the last semi-stable state before O–O bond formation and O2 evolution2,3. A detailed understanding of the O–O bond formation mechanism remains a challenge, and will require elucidation of both the structures of the OEC in the different S-states and the binding of the two substrate waters to the catalytic site4–6. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage-free, room temperature structures of dark-adapted (S1), two-flash illuminated (2F; S3-enriched), and ammonia-bound two-flash illuminated (2F-NH3; S3-enriched) PS II. Although the recent 1.95 Å resolution structure of PS II at cryogenic temperature using an XFEL7 provided a damage-free view of the S1 state, measurements at room temperature are required to study the structural landscape of proteins under functional conditions8,9, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analogue, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states10. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site10–13. This approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O–O bond formation mechanisms.

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