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  1. Article ; Online: Characterization of the Aerobic Anoxygenic Phototrophic Bacterium Sphingomonas sp. AAP5

    Karel Kopejtka / Yonghui Zeng / David Kaftan / Vadim Selyanin / Zdenko Gardian / Jürgen Tomasch / Ruben Sommaruga / Michal Koblížek

    Microorganisms, Vol 9, Iss 768, p

    2021  Volume 768

    Abstract: An aerobic, yellow-pigmented, bacteriochlorophyll a -producing strain, designated AAP5 (=DSM 111157=CCUG 74776), was isolated from the alpine lake Gossenköllesee located in the Tyrolean Alps, Austria. Here, we report its description and polyphasic ... ...

    Abstract An aerobic, yellow-pigmented, bacteriochlorophyll a -producing strain, designated AAP5 (=DSM 111157=CCUG 74776), was isolated from the alpine lake Gossenköllesee located in the Tyrolean Alps, Austria. Here, we report its description and polyphasic characterization. Phylogenetic analysis of the 16S rRNA gene showed that strain AAP5 belongs to the bacterial genus Sphingomonas and has the highest pairwise 16S rRNA gene sequence similarity with Sphingomonas glacialis (98.3%), Sphingomonas psychrolutea (96.8%), and Sphingomonas melonis (96.5%). Its genomic DNA G + C content is 65.9%. Further, in silico DNA-DNA hybridization and calculation of the average nucleotide identity speaks for the close phylogenetic relationship of AAP5 and Sphingomonas glacialis . The high percentage (76.2%) of shared orthologous gene clusters between strain AAP5 and Sphingomonas paucimobilis NCTC 11030 T , the type species of the genus, supports the classification of the two strains into the same genus. Strain AAP5 was found to contain C 18:1 ω 7 c (64.6%) as a predominant fatty acid (>10%) and the polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, six unidentified glycolipids, one unidentified phospholipid, and two unidentified lipids. The main respiratory quinone was ubiquinone-10. Strain AAP5 is a facultative photoheterotroph containing type-2 photosynthetic reaction centers and, in addition, contains a xathorhodopsin gene. No CO 2 -fixation pathways were found.
    Keywords aerobic anoxygenic phototrophic bacteria ; bacteriochlorophyll a ; photosynthesis genes ; rhodopsin ; Sphingomonadaceae ; Biology (General) ; QH301-705.5
    Subject code 572
    Language English
    Publishing date 2021-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article: Quenching of chlorophyll triplet states by carotenoids in algal light-harvesting complexes related to fucoxanthin-chlorophyll protein

    Khoroshyy, Petro / David Bína / Zdenko Gardian / Radek Litvín / Jan Alster / Jakub Pšenčík

    Photosynthesis research. 2018 Mar., v. 135, no. 1-3

    2018  

    Abstract: We have used time-resolved absorption and fluorescence spectroscopy with nanosecond resolution to study triplet energy transfer from chlorophylls to carotenoids in a protective process that prevents the formation of reactive singlet oxygen. The light- ... ...

    Abstract We have used time-resolved absorption and fluorescence spectroscopy with nanosecond resolution to study triplet energy transfer from chlorophylls to carotenoids in a protective process that prevents the formation of reactive singlet oxygen. The light-harvesting complexes studied were isolated from Chromera velia, belonging to a group Alveolata, and Xanthonema debile and Nannochloropsis oceanica, both from Stramenopiles. All three light-harvesting complexes are related to fucoxanthin-chlorophyll protein, but contain only chlorophyll a and no chlorophyll c. In addition, they differ in the carotenoid content. This composition of the complexes allowed us to study the quenching of chlorophyll a triplet states by different carotenoids in a comparable environment. The triplet states of chlorophylls bound to the light-harvesting complexes were quenched by carotenoids with an efficiency close to 100%. Carotenoid triplet states were observed to rise with a ~5 ns lifetime and were spectrally and kinetically homogeneous. The triplet states were formed predominantly on the red-most chlorophylls and were quenched by carotenoids which were further identified or at least spectrally characterized.
    Keywords Nannochloropsis ; absorption ; algae ; carotenoids ; chlorophyll ; energy transfer ; fluorescence emission spectroscopy ; singlet oxygen
    Language English
    Dates of publication 2018-03
    Size p. 213-225.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 1475688-2
    ISSN 1573-5079 ; 0166-8595
    ISSN (online) 1573-5079
    ISSN 0166-8595
    DOI 10.1007/s11120-017-0416-5
    Database NAL-Catalogue (AGRICOLA)

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  3. Article: Association of Psb28 and Psb27 Proteins with PSII-PSI Supercomplexes upon Exposure of Synechocystis sp. PCC 6803 to High Light

    Bečková, Martina / Jianfeng Yu / Josef Komenda / Peter J. Nixon / Peter Konik / Zdenko Gardian

    Molecular plant. 2017 Jan. 09, v. 10, no. 1

    2017  

    Abstract: Formation of the multi-subunit oxygen-evolving photosystem II (PSII) complex involves a number of auxiliary protein factors. In this study we compared the localization and possible function of two homologous PSII assembly factors, Psb28-1 and Psb28-2, ... ...

    Abstract Formation of the multi-subunit oxygen-evolving photosystem II (PSII) complex involves a number of auxiliary protein factors. In this study we compared the localization and possible function of two homologous PSII assembly factors, Psb28-1 and Psb28-2, from the cyanobacterium Synechocystis sp. PCC 6803. We demonstrate that FLAG-tagged Psb28-2 is present in both the monomeric PSII core complex and a PSII core complex lacking the inner antenna CP43 (RC47), whereas Psb28-1 preferentially binds to RC47. When cells are exposed to increased irradiance, both tagged Psb28 proteins additionally associate with oligomeric forms of PSII and with PSII-PSI supercomplexes composed of trimeric photosystem I (PSI) and two PSII monomers as deduced from electron microscopy. The presence of the Psb27 accessory protein in these complexes suggests the involvement of PSI in PSII biogenesis, possibly by photoprotecting PSII through energy spillover. Under standard culture conditions, the distribution of PSII complexes is similar in the wild type and in each of the single psb28 null mutants except for loss of RC47 in the absence of Psb28-1. In comparison with the wild type, growth of mutants lacking Psb28-1 and Psb27, but not Psb28-2, was retarded under high-light conditions and, especially, intermittent high-light/dark conditions, emphasizing the physiological importance of PSII assembly factors for light acclimation.
    Keywords acclimation ; biogenesis ; electron microscopy ; energy ; light intensity ; mutants ; photosystem I ; photosystem II ; proteins ; Synechocystis sp. PCC 6714 ; Synechocystis sp. PCC 6803
    Language English
    Dates of publication 2017-0109
    Size p. 62-72.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 2393618-6
    ISSN 1752-9867 ; 1674-2052
    ISSN (online) 1752-9867
    ISSN 1674-2052
    DOI 10.1016/j.molp.2016.08.001
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Modular antenna of photosystem I in secondary plastids of red algal origin: a Nannochloropsis oceanica case study

    Bína, David / Zdenko Gardian / Miroslava Herbstová / Radek Litvín

    Photosynthesis research. 2017 Mar., v. 131, no. 3

    2017  

    Abstract: Photosystem I (PSI) is a multi-subunit integral pigment–protein complex that performs light-driven electron transfer from plastocyanin to ferredoxin in the thylakoid membrane of oxygenic photoautotrophs. In order to achieve the optimal photosynthetic ... ...

    Abstract Photosystem I (PSI) is a multi-subunit integral pigment–protein complex that performs light-driven electron transfer from plastocyanin to ferredoxin in the thylakoid membrane of oxygenic photoautotrophs. In order to achieve the optimal photosynthetic performance under ambient irradiance, the absorption cross section of PSI is extended by means of peripheral antenna complexes. In eukaryotes, this role is played mostly by the pigment–protein complexes of the LHC family. The structure of the PSI-antenna supercomplexes has been relatively well understood in organisms harboring the primary plastid: red algae, green algae and plants. The secondary endosymbiotic algae, despite their major ecological importance, have so far received less attention. Here we report a detailed structural analysis of the antenna-PSI association in the stramenopile alga Nannochloropsis oceanica (Eustigmatophyceae). Several types of PSI-antenna assemblies are identified allowing for identification of antenna docking sites on the PSI core. Instances of departure of the stramenopile system from the red algal model of PSI-Lhcr structure are recorded, and evolutionary implications of these observations are discussed.
    Keywords Chlorophyta ; Nannochloropsis ; Rhodophyta ; absorption ; algae ; autotrophs ; case studies ; electron transfer ; eukaryotic cells ; light harvesting complex ; light intensity ; models ; photosystem I ; plastocyanin ; thylakoids
    Language English
    Dates of publication 2017-03
    Size p. 255-266.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 1475688-2
    ISSN 1573-5079 ; 0166-8595
    ISSN (online) 1573-5079
    ISSN 0166-8595
    DOI 10.1007/s11120-016-0315-1
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Pigment configuration in the light-harvesting protein of the xanthophyte alga Xanthonema debile

    Streckaite, Simona / Zdenko Gardian / Fei Li / Andrew A. Pascal / Radek Litvin / Bruno Robert / Manuel J. Llansola-Portoles

    Photosynthesis research. 2018 Nov., v. 138, no. 2

    2018  

    Abstract: The soil chromophyte alga Xanthonema (X.) debile contains only non-carbonyl carotenoids and Chl-a. X. debile has an antenna system denoted Xanthophyte light-harvesting complex (XLH) that contains the carotenoids diadinoxanthin, heteroxanthin, and ... ...

    Abstract The soil chromophyte alga Xanthonema (X.) debile contains only non-carbonyl carotenoids and Chl-a. X. debile has an antenna system denoted Xanthophyte light-harvesting complex (XLH) that contains the carotenoids diadinoxanthin, heteroxanthin, and vaucheriaxanthin. The XLH pigment stoichiometry was calculated by chromatographic techniques and the pigment-binding structure studied by resonance Raman spectroscopy. The pigment ratio obtained by HPLC was found to be close to 8:1:2:1 Chl-a:heteroxanthin:diadinoxanthin:vaucheriaxanthin. The resonance Raman spectra suggest the presence of 8–10 Chl-a, all of which are 5-coordinated to the central Mg, with 1–3 Chl-a possessing a macrocycle distorted from the relaxed conformation. The three populations of carotenoids are in the all-trans configuration. Vaucheriaxanthin absorbs around 500–530 nm, diadinoxanthin at 494 nm and heteroxanthin at 487 nm at 4.5 K. The effective conjugation length of heteroxanthin and diadinoxanthin has been determined as 9.4 in both cases; the environment polarizability of the heteroxanthin and diadinoxanthin binding pockets is 0.270 and 0.305, respectively.
    Keywords Raman spectroscopy ; algae ; carotenoids ; chlorophyll ; high performance liquid chromatography ; light harvesting complex ; magnesium ; soil ; stoichiometry
    Language English
    Dates of publication 2018-11
    Size p. 139-148.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 1475688-2
    ISSN 1573-5079 ; 0166-8595
    ISSN (online) 1573-5079
    ISSN 0166-8595
    DOI 10.1007/s11120-018-0557-1
    Database NAL-Catalogue (AGRICOLA)

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  6. Article ; Online: Production of Highly Active Recombinant Dermonecrotic Toxin of Bordetella Pertussis

    Ondrej Stanek / Irena Linhartova / Jana Holubova / Ladislav Bumba / Zdenko Gardian / Anna Malandra / Barbora Bockova / Shihono Teruya / Yasuhiko Horiguchi / Radim Osicka / Peter Sebo

    Toxins, Vol 12, Iss 596, p

    2020  Volume 596

    Abstract: Pathogenic Bordetella bacteria release a neurotropic dermonecrotic toxin (DNT) that is endocytosed into animal cells and permanently activates the Rho family GTPases by polyamination or deamidation of the glutamine residues in their switch II regions (e ... ...

    Abstract Pathogenic Bordetella bacteria release a neurotropic dermonecrotic toxin (DNT) that is endocytosed into animal cells and permanently activates the Rho family GTPases by polyamination or deamidation of the glutamine residues in their switch II regions (e.g., Gln63 of RhoA). DNT was found to enable high level colonization of the nasal cavity of pigs by B. bronchiseptica and the capacity of DNT to inhibit differentiation of nasal turbinate bone osteoblasts causes atrophic rhinitis in infected pigs. However, it remains unknown whether DNT plays any role also in virulence of the human pathogen B. pertussis and in pathogenesis of the whooping cough disease. We report a procedure for purification of large amounts of LPS-free recombinant DNT that exhibits a high biological activity on cells expressing the DNT receptors Cav3.1 and Cav3.2Electron microscopy and single particle image analysis of negatively stained preparations revealed that the DNT molecule adopts a V-shaped structure with well-resolved protein domains. These results open the way to structure–function studies on DNT and its interactions with airway epithelial layers.
    Keywords Bordetella ; GTPase ; deamidation ; dermonecrotic toxin ; recombinant ; electron microscopy ; negative staining ; image analysis ; Medicine ; R
    Subject code 630
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article: Architecture of the light-harvesting apparatus of the eustigmatophyte alga Nannochloropsis oceanica

    Litvín, Radek / David Bína / Miroslava Herbstová / Zdenko Gardian

    Photosynthesis research. 2016 Dec., v. 130, no. 1-3

    2016  

    Abstract: We present proteomic, spectroscopic, and phylogenetic analysis of light-harvesting protein (Lhc) function in oleaginous Nannochloropsis oceanica (Eustigmatophyta, Stramenopila). N. oceanica utilizes Lhcs of multiple classes: Lhcr-type proteins (related ... ...

    Abstract We present proteomic, spectroscopic, and phylogenetic analysis of light-harvesting protein (Lhc) function in oleaginous Nannochloropsis oceanica (Eustigmatophyta, Stramenopila). N. oceanica utilizes Lhcs of multiple classes: Lhcr-type proteins (related to red algae LHCI), Lhcv (VCP) proteins (violaxanthin-containing Lhcs related to Lhcf/FCP proteins of diatoms), Lhcx proteins (related to Lhcx/LhcSR of diatoms and green algae), and Lhc proteins related to Red-CLH of Chromera velia. Altogether, 17 Lhc-type proteins of the 21 known from genomic data were found in our proteomic analyses. Besides Lhcr-type antennas, a RedCAP protein and a member of the Lhcx protein subfamily were found in association with Photosystem I. The free antenna fraction is formed by trimers of a mixture of Lhcs of varied origins (Lhcv, Lhcr, Lhcx, and relatives of Red-CLH). Despite possessing several proteins of the Red-CLH-type Lhc clade, N. oceanica is not capable of chromatic adaptation under the same conditions as the diatom Phaeodactylum tricornutum or C. velia. In addition, a naming scheme of Nannochloropsis Lhcs is proposed to facilitate further work.
    Keywords algae ; Chlorophyta ; light harvesting complex ; Nannochloropsis ; Phaeodactylum tricornutum ; phylogeny ; proteomics ; Rhodophyta ; spectroscopy
    Language English
    Dates of publication 2016-12
    Size p. 137-150.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 1475688-2
    ISSN 1573-5079 ; 0166-8595
    ISSN (online) 1573-5079
    ISSN 0166-8595
    DOI 10.1007/s11120-016-0234-1
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: Unique double concentric ring organization of light harvesting complexes in Gemmatimonas phototrophica.

    Marko Dachev / David Bína / Roman Sobotka / Lenka Moravcová / Zdenko Gardian / David Kaftan / Václav Šlouf / Marcel Fuciman / Tomáš Polívka / Michal Koblížek

    PLoS Biology, Vol 15, Iss 12, p e

    2017  Volume 2003943

    Abstract: The majority of life on Earth depends directly or indirectly on the sun as a source of energy. The initial step of photosynthesis is facilitated by light-harvesting complexes, which capture and transfer light energy into the reaction centers (RCs). Here, ...

    Abstract The majority of life on Earth depends directly or indirectly on the sun as a source of energy. The initial step of photosynthesis is facilitated by light-harvesting complexes, which capture and transfer light energy into the reaction centers (RCs). Here, we analyzed the organization of photosynthetic (PS) complexes in the bacterium G. phototrophica, which so far is the only phototrophic representative of the bacterial phylum Gemmatimonadetes. The isolated complex has a molecular weight of about 800 ± 100 kDa, which is approximately 2 times larger than the core complex of Rhodospirillum rubrum. The complex contains 62.4 ± 4.7 bacteriochlorophyll (BChl) a molecules absorbing in 2 distinct infrared absorption bands with maxima at 816 and 868 nm. Using femtosecond transient absorption spectroscopy, we determined the energy transfer time between these spectral bands as 2 ps. Single particle analyses of the purified complexes showed that they were circular structures with an outer diameter of approximately 18 nm and a thickness of 7 nm. Based on the obtained, we propose that the light-harvesting complexes in G. phototrophica form 2 concentric rings surrounding the type 2 RC. The inner ring (corresponding to the B868 absorption band) is composed of 15 subunits and is analogous to the inner light-harvesting complex 1 (LH1) in purple bacteria. The outer ring is composed of 15 more distant BChl dimers with no or slow energy transfer between them, resulting in the B816 absorption band. This completely unique and elegant organization offers good structural stability, as well as high efficiency of light harvesting. Our results reveal that while the PS apparatus of Gemmatimonadetes was acquired via horizontal gene transfer from purple bacteria, it later evolved along its own pathway, devising a new arrangement of its light harvesting complexes.
    Keywords Biology (General) ; QH301-705.5
    Subject code 540
    Language English
    Publishing date 2017-12-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Molecular basis of chromatic adaptation in pennate diatom Phaeodactylum tricornutum

    Herbstová, Miroslava / David Bína / Peter Koník / Zdenko Gardian / František Vácha / Radek Litvín

    Biochimica et biophysica acta. 2015 June, July, v. 1847, no. 6-7

    2015  

    Abstract: The remarkable adaptability of diatoms living in a highly variable environment assures their prominence among marine primary producers. The present study integrates biochemical, biophysical and genomic data to bring new insights into the molecular ... ...

    Abstract The remarkable adaptability of diatoms living in a highly variable environment assures their prominence among marine primary producers. The present study integrates biochemical, biophysical and genomic data to bring new insights into the molecular mechanism of chromatic adaptation of pennate diatoms in model species Phaeodactylum tricornutum, a marine eukaryote alga possessing the capability to shift its absorption up to ~700nm as a consequence of incident light enhanced in the red component. Presence of these low energy spectral forms of Chl a is manifested by room temperature fluorescence emission maximum at 710nm (F710). Here we report a successful isolation of the supramolecular protein complex emitting F710 and identify a member of the Fucoxanthin Chlorophyll a/c binding Protein family, Lhcf15, as its key building block. This red-shifted antenna complex of P. tricornutum appears to be functionally connected to photosystem II. Phylogenetic analyses do not support relation of Lhcf15 of P. tricornutum to other known red-shifted antenna proteins thus indicating a case of convergent evolutionary adaptation towards survival in shaded environments.
    Keywords Phaeodactylum tricornutum ; absorption ; algae ; ambient temperature ; binding proteins ; chlorophyll ; energy ; eukaryotic cells ; evolutionary adaptation ; fluorescence ; phylogeny ; trophic relationships
    Language English
    Dates of publication 2015-06
    Size p. 534-543.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 282711-6
    ISSN 0005-2728 ; 0304-4173
    ISSN 0005-2728 ; 0304-4173
    DOI 10.1016/j.bbabio.2015.02.016
    Database NAL-Catalogue (AGRICOLA)

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  10. Article: Novel type of red-shifted chlorophyll a antenna complex from Chromera velia: II. Biochemistry and spectroscopy

    Bína, David / Zdenko Gardian / Miroslava Herbstová / Eva Kotabová / Peter Koník / Radek Litvín / Ondřej Prášil / Josef Tichý / František Vácha

    Biochimica et biophysica acta. 2014 June, v. 1837, no. 6

    2014  

    Abstract: A novel chlorophyll a containing pigment–protein complex expressed by cells of Chromera velia adapted to growth under red/far-red illumination [1]. Purification of the complex was achieved by means of anion-exchange chromatography and gel-filtration. The ...

    Abstract A novel chlorophyll a containing pigment–protein complex expressed by cells of Chromera velia adapted to growth under red/far-red illumination [1]. Purification of the complex was achieved by means of anion-exchange chromatography and gel-filtration. The antenna is shown to be an aggregate of ~20kDa proteins of the light–harvesting complex (LHC) family, unstable in the isolated form. The complex possesses an absorption maximum at 705nm at room temperature in addition to the main chlorophyll a maximum at 677nm producing the major emission band at 714nm at room temperature. The far-red absorption is shown to be the property of the isolated aggregate in the intact form and lost upon dissociation. The purified complex was further characterized by circular dichroism spectroscopy and fluorescence spectroscopy. This work thus identified the third different class of antenna complex in C. velia after the recently described FCP-like and LHCr-like antennas. Possible candidates for red antennas are identified in other taxonomic groups, such as eustigmatophytes and the relevance of the present results to other known examples of red-shifted antenna from other organisms is discussed. This work appears to be the first successful isolation of a chlorophyll a-based far-red antenna complex absorbing above 700nm unrelated to LHCI.
    Keywords Eustigmatophyceae ; absorption ; ambient temperature ; anion exchange chromatography ; chlorophyll ; circular dichroism spectroscopy ; dissociation ; fluorescence emission spectroscopy ; gel chromatography ; light harvesting complex ; lighting
    Language English
    Dates of publication 2014-06
    Size p. 802-810.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 282711-6
    ISSN 0005-2728 ; 0304-4173
    ISSN 0005-2728 ; 0304-4173
    DOI 10.1016/j.bbabio.2014.01.011
    Database NAL-Catalogue (AGRICOLA)

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