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  • 51. PALMQVIST, K
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    BADGER, MR
    PHOTOBIONT-RELATED DIFFERENCES IN CARBON ACQUISITION AMONG GREEN-ALGAL LICHENS1994Ingår i: Planta, ISSN 0032-0935, E-ISSN 1432-2048, Vol. 195, nr 1, s. 70-79Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The photosynthetic properties of a range of lichens (eight species) containing green algal primary photobionts of either the genus Coccomyxa, Dictyochloropsis or Trebouxia were examined with the aim of obtaining a better understanding for the different CO2 acquisition strategies of lichenized green algae. Fast transients of light/dark-dependent CO2 uptake and release were measured in order to screen for the presence or absence of a photosynthetic CO2-concentrating mechanism (CCM) within the photobiont. It was found that lichens with Trebouxia photobionts (four species) were able to accumulate a small pool of inorganic carbon (DIC; 70-140 nmol per mg chlorophyll (Chl)), in the light, which theoretically may result in, at least, a two- to threefold increase in the stromal CO2 concentration, as compared to that in equilibrium with ambient air. The other lichens (four species), which were tripartite associations between a fungus, a cyanobacterium (Nostoc) and a green alga (Coccomyxa or Dictyochloropsis) accumulated a much smaller pool of DIC (10-30 nmol.(mg Chl)(-1)). This pool is most probably associated with the previously documented CCM of Nostoc, inferred from the finding that free-living cells of Coccomyxa did not show any signs of DIC accumulation. In addition, the kinetics of fast CO2 exchange for free-living Nostoc were similar to those of intact tripartite lichens, especially in their responses to the CCM and the carbonic anhydrase (CA) inhibitor ethoxyzolamide. Trebouxia lichens had a higher photosynthetic capacity at low and limiting external CO2 concentrations, with an initial slope of the CO2-response curve of 2.6-3.9 mu mol.(mg Chl)-1.h(-1).Pa-1, compared to the tripartite lichens which had an initial slope of 0.5-1.1 mu mol.(mg Chl)(-1).h(-1).Pa-1, suggesting that the presence of a CCM in the photobiont affects the photosynthetic performance of the whole lichen. Regardless of these indications for the presence or absence of a CCM, ethoxyzolamide inhibited the steady-state rate of photosynthesis at low CO2 in all lichens, indicating a role of CA in the photosynthetic process within all of the photobionts. Measurements of CA activity in photobiont-enriched homogenates of the lichens showed that Coccomyxa had by far the highest activity, while the other photobionts displayed only traces or no activity at all. As the CCM is apparently absent in Coccomyxa, it is speculated that this alga compensates for this absence with high internal CA activity, which may function to reduce the CO2-diffusion resistance through the cell.

  • 52. PALMQVIST, K
    et al.
    SJOBERG, S
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    INDUCTION OF INORGANIC CARBON ACCUMULATION IN THE UNICELLULAR GREEN-ALGAE SCENEDESMUS-OBLIQUUS AND CHLAMYDOMONAS-REINHARDTII1988Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 87, nr 2, s. 437-442Artikel i tidskrift (Refereegranskat)
  • 53. PALMQVIST, K
    et al.
    SUNDBLAD, LG
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    SUNDBOM, E
    A CORRELATION BETWEEN CHANGES IN LUMINESCENCE DECAY KINETICS AND THE APPEARANCE OF A CO2-ACCUMULATING MECHANISM IN SCENEDESMUS OBLIQUUS1986Ingår i: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 10, nr 1-2, s. 113-123Artikel i tidskrift (Refereegranskat)
  • 54. PALMQVIST, K
    et al.
    SUNDBLAD, LG
    WINGSLE, G
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    ACCLIMATION OF PHOTOSYNTHETIC LIGHT REACTIONS DURING INDUCTION OF INORGANIC CARBON ACCUMULATION IN THE GREEN-ALGA CHLAMYDOMONAS-REINHARDTII1990Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 94, nr 1, s. 357-366Artikel i tidskrift (Refereegranskat)
  • 55. Park, Y I
    et al.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Rojdestvenski, I
    Pronina, N
    Klimov, V
    Oquist, Gunnar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Role of a novel photosystem II-associated carbonic anhydrase in photosynthetic carbon assimilation in Chlamydomonas reinhardtii1999Ingår i: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 444, nr 1, s. 102-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Intracellular carbonic anhydrases (CA) in aquatic photosynthetic organisms are involved in the CO2-concentrating mechanism (CCM), which helps to overcome CO2 limitation in the environment. In the green alga Chlamydomonas reinhardtii, this CCM is initiated and maintained by the pH gradient created across the chloroplast thylakoid membranes by photosystem (PS) II-mediated electron transport. We show here that photosynthesis is stimulated by a novel, intracellular alpha-CA bound to the chloroplast thylakoids. It is associated with PSII on the lumenal side of the thylakoid membranes. We demonstrate that PSII in association with this lumenal CA operates to provide an ample flux of CO2 for carboxylation. (C) 1999 Federation of European Biochemical Societies.

  • 56. PAWLIK, B
    et al.
    SKOWRONSKI, T
    RAMAZANOW, Z
    Gardeström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    PH-DEPENDENT CADMIUM TRANSPORT INHIBITS PHOTOSYNTHESIS IN THE CYANOBACTERIUM SYNECHOCYSTIS-AQUATILIS1993Ingår i: Environmental and Experimental Botany, ISSN 0098-8472, E-ISSN 1873-7307, Vol. 33, nr 2, s. 331-337Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Short-term (5-120 sec) transport of cadmium (Cd-109) into cells of the unicellular cyanobacterium Synechocystis aquatilis was studied using a rapid filtration technique. The transport was strongly pH-dependent, occurring at pH 7, but not at pH 5.5, and was also observed in long-term (40 min) experiments. For this process the optimum pH was approximately 7.5; uptake was considerably reduced at lower pHs. The entrance of cadmium disturbed photosynthetic activity and related processes. At pH 7, cadmium (8.9 muM) decreased CO2 fixation by about 55%, inhibited carbonic anhydrase activity (completely in intact cells, by 65%, in cell-free extracts) and photosynthetic O2-evolution by about 50%. At pH 5.5 no effects were observed.

  • 57. Pawlik, B
    et al.
    Skowroński, T
    Ramazanow, Z
    Gardeström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    pH-dependent cadmium transport inhibits photosynthesis in the cyanobacterium Synechocystis aquatilis1993Ingår i: Environmental and Experimental Botany, ISSN 0098-8472, E-ISSN 1873-7307, Vol. 33, nr 2, s. 331-337Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Short-term (5-120 sec) transport of cadmium (Cd-109) into cells of the unicellular cyanobacterium Synechocystis aquatilis was studied using a rapid filtration technique. The transport was strongly pH-dependent, occurring at pH 7, but not at pH 5.5, and was also observed in long-term (40 min) experiments. For this process the optimum pH was approximately 7.5; uptake was considerably reduced at lower pHs. The entrance of cadmium disturbed photosynthetic activity and related processes. At pH 7, cadmium (8.9 muM) decreased CO2 fixation by about 55%, inhibited carbonic anhydrase activity (completely in intact cells, by 65%, in cell-free extracts) and photosynthetic O2-evolution by about 50%. At pH 5.5 no effects were observed.

  • 58. PREZELIN, BB
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    MATLICK, HA
    PHOTOSYSTEM-II PHOTOINHIBITION AND ALTERED KINETICS OF PHOTOSYNTHESIS DURING NUTRIENT-DEPENDENT HIGHLIGHT PHOTOADAPTATION IN GONYAULAX-POLYEDRA1986Ingår i: Marine Biology, ISSN 0025-3162, E-ISSN 1432-1793, Vol. 93, nr 1, s. 1-12Artikel i tidskrift (Refereegranskat)
  • 59. RAVEN, JA
    et al.
    HANDLEY, LL
    MACFARLANE, JJ
    MCINROY, S
    MCKENZIE, L
    RICHARDS, JH
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    THE ROLE OF CO2 UPTAKE BY ROOTS AND CAM IN ACQUISITION OF INORGANIC C BY PLANTS OF THE ISOETID LIFE-FORM - A REVIEW, WITH NEW DATA ON ERIOCAULON-DECANGULARE L1988Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 108, nr 2, s. 125-148Artikel i tidskrift (Refereegranskat)
  • 60. RAVEN, JA
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    ECOPHYSIOLOGY OF FUCUS-VESICULOSUS L CLOSE TO ITS NORTHERN LIMIT IN THE GULF OF BOTHNIA1988Ingår i: Botanica Marina, ISSN 0006-8055, E-ISSN 1437-4323, Vol. 31, nr 5, s. 399-410Artikel i tidskrift (Refereegranskat)
  • 61. RAVEN, JA
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    REPAIR OF PHOTOINHIBITORY DAMAGE IN ANACYSTIS-NIDULANS-625 (SYNECHOCOCCUS-6301) - RELATION TO CATALYTIC CAPACITY FOR, AND ENERGY SUPPLY TO, PROTEIN-SYNTHESIS, AND IMPLICATIONS FOR MU-MAX AND THE EFFICIENCY OF LIGHT-LIMITED GROWTH1986Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 103, nr 4, s. 625-643Artikel i tidskrift (Refereegranskat)
  • 62.
    Renberg, Linda
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Johansson, Annika I.
    Shutova, Tatiana
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Stenlund, Hans
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Aksmann, Anna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Raven, John A.
    Gardeström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Moritz, Thomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    A metabolomic approach to study major metabolite changes during acclimation to limiting CO2 in chlamydomonas reinhardtii2010Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 154, nr 1, s. 187-196Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a gas chromatography-mass spectrometry-time of flight technique, we determined major metabolite changes during induction of the carbon-concentrating mechanism in the unicellular green alga Chlamydomonas reinhardtii. In total, 128 metabolites with significant differences between high-and low-CO2-grown cells were detected, of which 82 were wholly or partially identified, including amino acids, lipids, and carbohydrates. In a 24-h time course experiment, we show that the amino acids serine and phenylalanine increase transiently while aspartate and glutamate decrease after transfer to low CO2. The biggest differences were typically observed 3 h after transfer to low-CO2 conditions. Therefore, we made a careful metabolomic examination at the 3-h time point, comparing low-CO2 treatment to high-CO2 control. Five metabolites involved in photorespiration, 11 amino acids, and one lipid were increased, while six amino acids and, interestingly, 21 lipids were significantly lower. Our conclusion is that the metabolic pattern during early induction of the carbon-concentrating mechanism fit a model where photorespiration is increasing.

  • 63. Richardson, Katherine
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Hällgren, Jan-Erik
    The relationship between photosynthesis measured by C-14 incorporation and by uptake of inorganic carbon in unicellular algae1984Ingår i: Journal of Experimental Marine Biology and Ecology, ISSN 0022-0981, E-ISSN 1879-1697, Vol. 81, nr 3, s. 241-250Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The traditional 14C method of estimating photosynthetic rates was compared with net photo-synthesis in two species of unicellular algae. Net photosynthesis was defined as the disappearance of inorganic carbon from the algal medium and was determined using a described infra-red gas analyser (IRGA) technique. For Amphidinium carterae Hulbert, the 14C method always led to lower calculated rates of photosynthesis than the IRGA technique. This difference was, on average, ≈100%. For Scenedesmusobliquus (Turpin) Kützing, the 14C method could lead to over-estimates, good agreement with, or underestimates of net photosynthesis. Although the under-estimates were only of the order of 15%, the over-estimates were in some cases > 100%. There is some indication that respiration rate is an important factor in the relationship between photosynthetic rates calculated by the two methods for this organism.

  • 64. Rojdestvenski, I
    et al.
    Park, Y I
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Oquist, Gunnar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    A carbonic anhydrase catalyzed CO2 pump in Chlamydomonas reinhardtii: In vivo experiments, computer modelling, and theory2000Ingår i: Russian journal of plant physiology, ISSN 1021-4437, E-ISSN 1608-3407, Vol. 47, nr 5, s. 613-621Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We studied the bicarbonate depletion effects on photosynthesis in high-CO2 grown-cell wall-less mutants of Chlamydomonas reinhardtii with (cw92) and without (cia3/cw15) active carbonic anhydrase (CA) associated with photosystem II (PSII). The mutants were grown in a high-CO2 medium and then washed with a CO2-free buffer. We discuss the shutdown of oxygen evolution in cw92 as a consequence of CO2 depletion of the Calvin cycle. It is suggested that CA acts as part of a PSII-driven pump delivering CO2 from the lumen into the stroma, where it becomes available to the Calvin cycle. Our model is supported by computer simulation data and accommodates the results of in vivo experiments as well as the differences between cw92 and cia3 mutants. We also present a simple theory of the phenomena discussed, based on a time-scale hierarchy approach, which describes the CO2 depletion in cw92 using only two rate constants-V-max and K-m of the Calvin cycle.

  • 65. Rouhier, Nicolas
    et al.
    Gelhaye, Eric
    Dietz, Karl Josef
    Jacquot, Jean-Pierre
    Wingsle, Gunnar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Villarejo, Arsenio
    Srivastava, Manoj
    Keech, Olivier
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Droux, Michel
    Finkemeier, Iris
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Identification of plant glutaredoxin targets2005Ingår i: Antioxidants and Redox Signaling, ISSN 1523-0864, E-ISSN 1557-7716, Vol. 7, nr 7-8, s. 919-929Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Glutaredoxins (Grxs) are small ubiquitous proteins of the thioredoxin (Trx) family, which catalyze dithiol–disulfide exchange reactions or reduce protein-mixed glutathione disulfides. In plants, several Trx-interacting proteins have been isolated from different compartments, whereas very few Grx-interacting proteins are known. We describe here the determination of Grx target proteins using a mutated poplar Grx, various tissular and subcellular plant extracts, and liquid chromatography coupled to tandem mass spectrometry detection. We have identified 94 putative targets, involved in many processes, including oxidative stress response [peroxiredoxins (Prxs), ascorbate peroxidase, catalase], nitrogen, sulfur, and carbon metabolisms (methionine synthase, alanine aminotransferase, phosphoglycerate kinase), translation (elongation factors E and Tu), or protein folding (heat shock protein 70). Some of these proteins were previously found to interact with Trx or to be glutathiolated in other organisms, but others could be more specific partners of Grx. To substantiate further these data, Grx was shown to support catalysis of the stroma β-type carbonic anhydrase and Prx IIF of Arabidopsis thaliana, but not of poplar 2-Cys Prx. Overall, these data suggest that the interaction could occur randomly either with exposed cysteinyl disulfide bonds formed within or between target proteins or with mixed disulfides between a protein thiol and glutathione.

  • 66.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    The use of fluorescence techniques for the study of some membrane-bound photosynthetic properties and some effects of copper on the thylakoid membrane1981Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Lyophilized pea chloroplasts were extracted in a stepwise manner in an organic solvent (petroleum ether) with increasing polarity which was obtained by addition of small amount of ETOH (0-1 %). Absorption and low temperature fluorescence emission spectra were measured on both the extracted thylakoids and on isolated chlorophylI-protein complexes. Extraction of chlorophyll from the membrane increased (and the ratio of chlorophyl l a/b decreased) with increasing polarity of the solvent. The gel scan revealed that after extraction with petroleum ether, CPa.. was lost from the gel and after extraction with petroleum ether +1 % ETOH only the CPa/b was left together with SDS-free chlorophyll. This shows that the chlorophyll in CPa/b are situated in a less hydrophobic environment than chlorophyll in CPa|| and CPa|. The long wavelength absorbing and emitting chlorophyll fraction associated to CPaj was found to be easily removed from the membrane. This caused a blue shift in the low temperature fluorescence emission peak and in the red absorption peak and it was also accompanied by a decrease in carote-noid absorption in isolated CPa|. It was found in different plant material lacking $-carotene in CPàj that a strong correlation between ß-carotene in CPa. and the existence of the long wavelength chlorophyll in isolated cPa. existed. Based on these data, it was suggested that excited chlorophyll can transfer energy in excess to ß-carotene by a triplet--triplet transfer.A method based on in vivo chlorophyll £ fluorescence was developed for studying photosynthetic capacity in unicellular algae. It was shown that DCMU-induced fluorescence increase was a good measure of photosynthetic capacity in four species of green algae tested.The effect of copper chloride on photosynthetic electron transport and chlorophyl1-protein complexes was studied in spinach chloroplasts. Copper(11) inhibited a PS I i reaction H2O—> DPIP, a PS I reaction Asc/DPIP —> NADP and the overall electron transport H2O —> NAOP to different degrees. Chlorophyll protein complexes were only slightly affected by copper(ll) but with both copper and ascorbate in the reaction media, a rapid membrane destruction occurred. This was probably caused by a free radical reaction catalyzed by copper(ll).

  • 67.
    Samuelsson, Göran
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    LONNEBORG, A
    Gustafsson, Petter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Oquist, Gunnar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    THE SUSCEPTIBILITY OF PHOTOSYNTHESIS TO PHOTOINHIBITION AND THE CAPACITY OF RECOVERY IN HIGH AND LOW LIGHT GROWN CYANOBACTERIA, ANACYSTIS-NIDULANS1987Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 83, nr 2, s. 438-441Artikel i tidskrift (Refereegranskat)
  • 68.
    Samuelsson, Göran
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    OQUIST, G
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    EFFECTS OF COPPER CHLORIDE ON PHOTOSYNTHETIC ELECTRON-TRANSPORT AND CHLOROPHYLL-PROTEIN COMPLEXES OF SPINACIA-OLERACEA1980Ingår i: Plant and Cell Physiology, ISSN 0032-0781, E-ISSN 1471-9053, Vol. 21, nr 3, s. 445-454Artikel i tidskrift (Refereegranskat)
  • 69.
    Samuelsson, Göran
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    RICHARDSON, K
    PHOTOINHIBITION AT LOW QUANTUM FLUX DENSITIES IN A MARINE DINOFLAGELLATE (AMPHIDINIUM-CARTERAE)1982Ingår i: Marine Biology, ISSN 0025-3162, E-ISSN 1432-1793, Vol. 70, nr 1, s. 21-26Artikel i tidskrift (Refereegranskat)
  • 70.
    Shevela, Dmitriy
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Nöring, Birgit
    Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Koroidov, Sergey
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Shutova, Tatyana
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Messinger, Johannes
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Max Planck Institute for Chemical Energy Conversion, Mülheim, Germany.
    Efficiency of photosynthetic water oxidation at ambient and depleted levels of inorganic carbon2013Ingår i: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 117, nr 1-3, s. 401-412Artikel i tidskrift (Refereegranskat)
    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.

  • 71.
    Shitov, A V
    et al.
    Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow, Russia.
    Zharmukhamedov, S K
    Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow, Russia.
    Shutova, Tatiana
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Allakhverdiev, S I
    Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow, Russia.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Klimov, V V
    Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow, Russia.
    A carbonic anhydrase inhibitor induces bicarbonate-reversible suppression of electron transfer in pea photosystem 2 membrane fragments2011Ingår i: Journal of Photochemistry and Photobiology. B: Biology, ISSN 1011-1344, E-ISSN 1873-2682, Vol. 104, nr 1-2, s. 366-371Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effects of suppression of the carbonic anhydrase (CA) activity by a CA-inhibitor, acetazolamide (AA), on the photosynthetic activities of photosystem II (PS II) particles from higher plants were investigated. AA along with CA-activity inhibits the PS II photosynthetic electron transfer and the AA-induced suppression is totally reversed by the addition of bicarbonate (3-5 mM). Similar effect of recovery in the PS II photosynthetic activity was also revealed upon the addition of known artificial electron donors (potassium ferrocyanide and TMPD). Significance and possible functions of CA for the PS II donor side are discussed.

  • 72.
    Shutova, Tatiana
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Villarejo, A
    Zietz, B
    Klimov, Vyacheslav
    Gillbro, T
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Renger, G
    Comparative studies on the properties of the extrinsic manganese-stabilizing protein from higher plants and of a synthetic peptide of its C-terminus2003Ingår i: Biochimica et biophysica acta. Bioenergetics, ISSN 0005-2728, Vol. 1604, nr 2, s. 95-104Artikel i tidskrift (Refereegranskat)
  • 73.
    Shutova, Tatyana
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Kenneweg, Hella
    Buchta, Joachim
    Nikitina, Julia
    Terentyev, Vasily
    Chernyshov, Sergey
    Andersson, Bertil
    Allakhverdiev, Suleyman I
    Klimov, Vyacheslav V
    Dau, Holger
    Junge, Wolfgang
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    The photosystem II-associated Cah3 in Chlamydomonas enhances the O(2) evolution rate by proton removal2008Ingår i: EMBO Journal, ISSN 0261-4189, E-ISSN 1460-2075, Vol. 27, s. 782-791Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water oxidation in photosystem II (PSII) is still insufficiently understood and is assumed to involve HCO3-. A Chlamydomonas mutant lacking a carbonic anhydrase associated with the PSII donor side shows impaired O2 evolution in the absence of HCO3-. The O2 evolution for saturating, continuous illumination (RO2) was slower than in the wild type, but was elevated by HCO3- and increased further by Cah3. The RO2 limitation in the absence of Cah3/HCO3- was amplified by H2O/D2O exchange, but relieved by an amphiphilic proton carrier, suggesting a role of Cah3/HCO3- in proton translocation. Chlorophyll fluorescence indicates a Cah3/HCO3- effect at the donor side of PSII. Time-resolved delayed fluorescence and O2-release measurements suggest specific effects on proton-release steps but not on electron transfer. We propose that Cah3 promotes proton removal from the Mn complex by locally providing HCO3-, which may function as proton carrier. Without Cah3, proton removal could become rate limiting during O2 formation and thus, limit water oxidation under high light. Our results underlie the general importance of proton release at the donor side of PSII during water oxidation.

  • 74.
    Shutova, Tatyana
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Klimov, Vyacheslav V
    Andersson, Bertil
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    A cluster of carboxylic groups in PsbO protein is involved in proton transfer from the water oxidizing complex of Photosystem II.2007Ingår i: Biochimica et Biophysica Acta - Bioenergetics, ISSN 0005-2728, E-ISSN 1879-2650, Vol. 1767, s. 434-440Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The hypothesis presented here for proton transfer away from the water oxidation complex of Photosystem II (PSII) is supported by biochemical experiments on the isolated PsbO protein in solution, theoretical analyses of better understood proton transfer systems like bacteriorhodopsin and cytochrome oxidase, and the recently published 3D structure of PS II (Pdb entry 1S5L). We propose that a cluster of conserved glutamic and aspartic acid residues in the PsbO protein acts as a buffering network providing efficient acceptors of protons derived from substrate water molecules. The charge delocalization of the cluster ensures readiness to promptly accept the protons liberated from substrate water. Therefore protons generated at the catalytic centre of PSII need not be released into the thylakoid lumen as generally thought. The cluster is the beginning of a localized, fast proton transfer conduit on the lumenal side of the thylakoid membrane. Proton-dependent conformational changes of PsbO may play a role in the regulation of both supply of substrate water to the water oxidizing complex and the resultant proton transfer.

  • 75.
    Shutova, Tatyana
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Nikitina, Julia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Deikus, Gintaras
    Andersson, Bertil
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik.
    Klimov, Vyacheslav
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Structural dynamics of the manganese-stabilizing protein-effect of pH, calcium, and manganese2005Ingår i: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 44, nr 46, s. 15182-15192Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The photosystem-II-associated 33-kDa extrinsic manganese-stabilizing protein is found in all oxygen-evolving organisms. In this paper, we show that this protein undergoes pH-induced conformational changes in the physiological pH range. At a neutral pH of 7.2, the hydrophobic amino acid residues that are most likely located inside the barrel are "closed" and the protein binds neither Mn2+ nor Ca2+ ions. When the protein is transferred to a solution with a slightly acidic pH of 5.7, hydrophobic amino acid residues become exposed to the surrounding medium, enabling them to bind the fluorescent probe 8,1-ANS. At this pH-induced open state, Mn2+ and Ca2+ bind to the manganese-stabilizing protein. The pH values used in this study, 7.2 and 5.7, are typical of the pH found in the thylakoid lumen in the dark and light, respectively. A model is presented in which the manganese-stabilizing protein undergoes a pH-dependent conformational change that in turn influences its capacity to bind calcium and manganese. In this model, the proton-dependent conformational changes of the tertiary structure of the manganese-stabilizing protein are of functional relevance for the regulation of substrate (water) delivery to and product (proton) release from the water-oxidizing complex by forming a proton-sensing proton-transport pathway.

  • 76. Siedlecka, A
    et al.
    Gardestrom, P
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, G
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Kleczkowski, L A
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Krupa, Z
    A relationship between carbonic anhydrase and rubisco in response to moderate cadmium stress during light activation of photosynthesis1999Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 54, nr 9-10, s. 759-763Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In our previous research, we showed that low Cd concentration increases the effectiveness of the process es leading to activation of ribulose-1,5-bisphosphate carboxylase/oxygen ase (Rubisco). This stimulation was dependent on carbonic anhydrase (CA) activity and resulted in protecting Rubisco activity against Cd toxicity. The aim of the present paper was to test whether this mechanism has any influence on light activation of photosynthesis during the first 2 h of illumination. Both the "activation mechanism" of plant response to Cd-stress conditions and its full efficiency at low Cd concentration were confirmed. The CA-dependent light activation of Rubisco at low Cd level was correlated with accelerated attaining of the maximum Rubisco activity by these plants. The amount of Rubisco was also Cd- and time-dependent and varied from continuous accumulation in control plants till reaching the maximum level within 30 minutes for the high Cd concentration. An increase in CA activity that was found to be parallel to the decrease of the amount of CA suggested activation of the enzyme by low Cd concentration.

  • 77. Siedlecka, A
    et al.
    Krupa, Z
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Oquist, Gunnar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Gardeström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Primary carbon metabolism in Phaseolus vulgaris plants under Cd/Fe interaction1997Ingår i: Plant physiology and biochemistry (Paris), ISSN 0981-9428, E-ISSN 1873-2690, Vol. 35, nr 12, s. 951-957Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The influence of the Cd/Fe interaction on primary carbon metabolism in Phaseolus vulgaris L. cv. Slowianka plants was investigated. It was documented earlier that Cd induced a decrease in the leaf Fe content, and increased levels of Fe may reduce Cd toxicity. The aim of the present study was to check whether Cd is toxic to Calvin cycle enzymes and especially if different Fe levels can modify the Cd effect. Bush-bean seedlings were cultivated in the presence of different Cd concentrations (0, 10, 20, 50 mu M) and at different Fe doses (deficient: 0 mmol, normal: 0.25 mmol, excessive: 0.5 mmol). Leaf content of ATP, ADP, Calvin cycle metabolites, activity of RUBISCO and carbonic anhydrase were measured. The influence of Cd/Fe interaction on the content of Calvin cycle metabolites seemed to be of both direct and indirect nature. The Cd-induced increase in ATP content, and in the ATP/ADP ratio, resulted from a decreased ATP consumption. At a higher Fe dose, the Cd/Fe interaction resulted in a revitalisation of the adenylate pool and Calvin cycle metabolites. The inhibition of RUBISCO carboxylase activity may be considered as the primary plant response to Cd-stress. The mechanisms of RUBISCO activation operate to overcome this limitation, although their efficiency was decreased by high Cd concentrations, resulting in decreased RUBISCO activity. At a low Cd concentration, the increase in RUBISCO activity was correlated with increased carbonic anhydrase activity.

  • 78. SUNDBLAD, LG
    et al.
    PALMQVIST, K
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    AN ENERGY-DEPENDENT, TRANSIENT PEAK IN THE MINUTE RANGE DECAY OF LUMINESCENCE, PRESENT IN CO2-ACCUMULATING CELLS OF SCENEDESMUS-OBLIQUUS1986Ingår i: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 199, nr 1, s. 75-79Artikel i tidskrift (Refereegranskat)
  • 79. SUNDBLAD, LG
    et al.
    PALMQVIST, K
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    LUMINESCENCE DECAY KINETICS IN RELATION TO THE RELAXATION OF THE TRANSTHYLAKOID DELTA-PH FROM HIGH AND LOW CO2 ADAPTED CELLS OF SCENEDESMUS-OBLIQUUS1986Ingår i: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 209, nr 1, s. 28-32Artikel i tidskrift (Refereegranskat)
  • 80. SUNDBLAD, LG
    et al.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    WIGGE, B
    Gardeström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    LUMINESCENCE DECAY KINETICS IN RELATION TO QUENCHING AND STIMULATION OF DARK FLUORESCENCE FROM HIGH AND LOW CO2 ADAPTED CELLS OF SCENEDESMUS-OBLIQUUS AND CHLAMYDOMONAS-REINHARDTII1990Ingår i: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 23, nr 3, s. 269-282Artikel i tidskrift (Refereegranskat)
  • 81. Villand, P
    et al.
    Eriksson, Mats
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Carbon dioxide and light regulation of promoters controlling the expression of mitochondrial carbonic anhydrase in Chlamydomonas reinhardtii1997Ingår i: Biochemical Journal, ISSN 0264-6021, E-ISSN 1470-8728, Vol. 327, s. 51-57Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nuclear genes coding for carbonic anhydrase, a major mitochondrial constituent in Chlamydomonas reinhardtii grown under limited CO2, were characterized. Two genes, ca1 and ca2, were found within 7 kb of genomic DNA, organized 'head to head' in a large inverted repeat. The DNA sequences for the two genes were very similar, even in the promoter regions and in introns, indicating that the repeat is a result of a recent duplication. To study gene regulation, elements from the upstream region of cal were fused to the arylsulphatase reporter gene. After transformation,the expression of arylsulphatase was regulated similarly to the endogenous ca1/ca2 genes, even when the promoter was trimmed down to 194 nt. Expression could not be detected when 5% CO2 was bubbled into the growth medium, but was induced within hours after transfer to air. The cal promoter was not induced in low light, but at intermediate light levels its activity was dependent on the irradiance. O-2 concentration had no effect on the promoter activity, indicating that photorespiratory metabolites are not triggering the response. The availability of cells transformed with a CO2-regulated reporter gene should facilitate further studies on the metabolic adaptations that occur in some green algae in response to the external CO2 level.

  • 82.
    Villarejo, Arsenio
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Burén, Stefan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Larsson, Susanne
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Déjardin, Annabelle
    Unité d'Amélioration, de Génétique et de Physiologie Forestières, INRA, BP 20619 Ardon, F-45166 Olivet Cedex, France.
    Monné, Magnus
    Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University.
    Rudhe, Charlotta
    Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Jansson, Stefan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Lerouge, Patrice
    University of Rouen, Mont Saint Aignan, France.
    Rolland, Norbert
    Université Joseph Fourier, Grenoble, France.
    von Heijne, Gunnar
    Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University.
    Grebe, Markus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Bako, Laszlo
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Evidence for a protein transported through the secretory pathway en route to the higher plant chloroplast.2005Ingår i: Nature Cell Biology, ISSN 1465-7392, Vol. 7, nr 12, s. 1224-31Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In contrast to animal and fungal cells, green plant cells contain one or multiple chloroplasts, the organelle(s) in which photosynthetic reactions take place. Chloroplasts are believed to have originated from an endosymbiotic event and contain DNA that codes for some of their proteins. Most chloroplast proteins are encoded by the nuclear genome and imported with the help of sorting signals that are intrinsic parts of the polypeptides. Here, we show that a chloroplast-located protein in higher plants takes an alternative route through the secretory pathway, and becomes N-glycosylated before entering the chloroplast.

  • 83. Villarejo, Arsenio
    et al.
    Shutova, Tatiana
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Moskvin, Oleg
    Forssén, Magnus
    Klimov, Vyacheslav V.
    Samuelsson, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    A photosystem II-associated carbonic anhydrase regulates the efficiency of photosynthetic oxygen evolution2002Ingår i: The EMBO Journal, ISSN 0261-4189, Vol. 21, nr 8, s. 1930–1938-Artikel i tidskrift (Refereegranskat)
12 51 - 83 av 83
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