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Dlouhý O, Kurasová I, Karlický V, Javornik U, Šket P, Petrova NZ, Krumova SB, Plavec J, Ughy B, Špunda V, Garab G. Modulation of non-bilayer lipid phases and the structure and functions of thylakoid membranes: effects on the water-soluble enzyme violaxanthin de-epoxidase. Sci Rep 2020; 10:11959. [PMID: 32686730 PMCID: PMC7371714 DOI: 10.1038/s41598-020-68854-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 06/26/2020] [Indexed: 12/19/2022] Open
Abstract
The role of non-bilayer lipids and non-lamellar lipid phases in biological membranes is an enigmatic problem of membrane biology. Non-bilayer lipids are present in large amounts in all membranes; in energy-converting membranes they constitute about half of their total lipid content—yet their functional state is a bilayer. In vitro experiments revealed that the functioning of the water-soluble violaxanthin de-epoxidase (VDE) enzyme of plant thylakoids requires the presence of a non-bilayer lipid phase. 31P-NMR spectroscopy has provided evidence on lipid polymorphism in functional thylakoid membranes. Here we reveal reversible pH- and temperature-dependent changes of the lipid-phase behaviour, particularly the flexibility of isotropic non-lamellar phases, of isolated spinach thylakoids. These reorganizations are accompanied by changes in the permeability and thermodynamic parameters of the membranes and appear to control the activity of VDE and the photoprotective mechanism of non-photochemical quenching of chlorophyll-a fluorescence. The data demonstrate, for the first time in native membranes, the modulation of the activity of a water-soluble enzyme by a non-bilayer lipid phase.
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Affiliation(s)
- Ondřej Dlouhý
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Irena Kurasová
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic.,Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - Václav Karlický
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic.,Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - Uroš Javornik
- Slovenian NMR Center, National Institute of Chemistry, Ljubljana, Slovenia
| | - Primož Šket
- Slovenian NMR Center, National Institute of Chemistry, Ljubljana, Slovenia.,EN-FIST Center of Excellence, Ljubljana, Slovenia
| | - Nia Z Petrova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Sashka B Krumova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Ljubljana, Slovenia.,EN-FIST Center of Excellence, Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Bettina Ughy
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic. .,Institute of Plant Biology, Biological Research Centre, Szeged, Hungary.
| | - Vladimír Špunda
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic. .,Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic.
| | - Győző Garab
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic. .,Institute of Plant Biology, Biological Research Centre, Szeged, Hungary.
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Garab G. Self-assembly and structural-functional flexibility of oxygenic photosynthetic machineries: personal perspectives. PHOTOSYNTHESIS RESEARCH 2016; 127:131-50. [PMID: 26494196 DOI: 10.1007/s11120-015-0192-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 09/02/2015] [Indexed: 05/24/2023]
Abstract
This short review, with a bit of historical aspect and a strong personal bias and emphases on open questions, is focusing on the (macro-)organization and structural-functional flexibilities of the photosynthetic apparatus of oxygenic photosynthetic organisms at different levels of the structural complexity-selected problems that have attracted most my attention in the past years and decades. These include (i) the anisotropic organization of the pigment-protein complexes and photosynthetic membranes-a basic organizing principle of living matter, which can, and probably should be adopted to intelligent materials; (ii) the organization of protein complexes into chiral macrodomains, large self-assembling highly organized but structurally flexible entities with unique spectroscopic fingerprints-structures, where, important, high-level regulatory functions appear to 'reside'; (iii) a novel, dissipation-assisted mechanism of structural changes, based on a thermo-optic effect: ultrafast thermal transients in the close vicinity of dissipation of unused excitation energy, which is capable of inducing elementary structural changes; it makes plants capable of responding to excess excitation with reaction rates proportional to the overexcitation above the light-saturation of photosynthesis; (iv) the 3D ultrastructure of the granum-stroma thylakoid membrane assembly and other multilamellar membrane systems, and their remodelings-associated with regulatory mechanisms; (v) the molecular organization and structural-functional plasticity of the main light-harvesting complex of plants, in relation to their crystal structure and different in vivo and in vitro states; and (vi) the enigmatic role of non-bilayer lipids and lipid phases in the bilayer thylakoid membrane-warranting its high protein content and contributing to its structural flexibility.
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