hh.sePublications
Change search
Refine search result
1 - 9 of 9
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Atteia, A.
    et al.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    van Lis, R.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Wetterskog, Daniel
    Department of Plant Physiology, Göteborg University, Göteborg, Sweden.
    Gutiérrez-Cirlos, E.-B.
    Department of Biochemistry, Dartmouth Medical School, Hanover, United States.
    Ongay-Larios, L.
    Unidad de Biología Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, D.
    Depto. de Genética Molecular, Inst. de Fisiología Celular, Univ. Nacl. Auton. de Mex., Mexico.
    Structure, organization and expression of the genes encoding mitochondrial cytochrome c1 and the Rieske iron-sulfur protein in Chlamydomonas reinhardtii2003In: Molecular Genetics and Genomics, ISSN 1617-4615, E-ISSN 1617-4623, Vol. 268, no 5, p. 637-644Article in journal (Refereed)
    Abstract [en]

    The sequence and organization of the Chlamydomonas reinhardtii genes encoding cytochrome c 1 ( Cyc1) and the Rieske-type iron-sulfur protein ( Isp), two key nucleus-encoded subunits of the mitochondrial cytochrome bc 1 complex, are presented. Southern hybridization analysis indicates that both Cyc1 and Isp are present as single-copy genes in C. reinhardtii. The Cyc1 gene spans 6404 bp and contains six introns, ranging from 178 to 1134 bp in size. The Isp gene spans 1238 bp and contains four smaller introns, ranging in length from 83 to 167 bp. In both genes, the intron/exon junctions follow the GT/AG rule. Internal conserved sequences were identified in only some of the introns in the Cyc1 gene. The levels of expression of Isp and Cyc1 genes are comparable in wild-type C. reinhardtii cells and in a mutant strain carrying a deletion in the mitochondrial gene for cytochrome b (dum-1). Nevertheless, no accumulation of the nucleus-encoded cytochrome c 1 or of core proteins I and II was observed in the membranes of the respiratory mutant. These data show that, in the green alga C. reinhardtii, the subunits of the cytochrome bc1 complex fail to assemble properly in the absence of cytochrome b.

  • 2.
    Cardol, Pierre
    et al.
    Genetics of Microorganisms, University of Liège, Liège, Belgium.
    Figueroa, Francisco
    Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba. Campus de Rabanalles, Edif. Severo Ochoa, Córdoba, Spain.
    Remacle, Claire
    Genetics of Microorganisms, University of Liège, Liège, Belgium.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, Diego
    Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Colonia Copilco-Universidad, Delegación Coyoacán, México D.F., Mexico.
    Oxidative Phosphorylation: Building blocks and related components2009In: The Chlamydomonas Sourcebook: Organellar and Metabolic Processes, Volume 2, Second Edition / [ed] Elizabeth H. Harris, David B. Stern & George B. Witman, Oxford: Academic Press, 2009, p. 469-502Chapter in book (Other academic)
    Abstract [en]

    This chapter summarizes the knowledge of the oxidative phosphorylation (OXPHOS) constituents of Chlamydomonas and of the components involved in their biogenesis and addresses alternate dehydrogenases and oxidases which are particular to photosynthetic organisms, and several other mitochondrial components related to OXPHOS. Reference to the components of Polytomella sp., a colorless alga closely related to Chlamydomonas is clearly made. The main complexes involved in electron transport seem to share a similar number of subunits, and many of the algal polypeptides have plant homologues. Some differences are apparent, such as the presence of a fragmented COX2 subunit, which seems to be unique to chlorophyte algae. OXPHOS is defined as an electron transfer chain driven by substrate oxidation that is coupled to the synthesis of ATP through an electrochemical transmembrane gradient. The characterization of Arabidopsis mitochondrial components through proteomic approaches has advanced significantly. As a unicellular organism, Chlamydomonas offers the unique opportunity to study organelle-organelle interactions, particularly between mitochondria and chloroplasts. It has become evident that crosstalk between these organelles takes place, mainly through intracellular metabolite pools. © 2009 Elsevier Inc. All rights reserved.

  • 3.
    Eriksson, K.M.
    et al.
    Department of Plant and Environmental Sciences, University of Gothenburg, Sweden.
    Clarke, A.K.
    Department of Plant and Environmental Sciences, University of Gothenburg, Sweden.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    Kuylenstierna, M.
    Department of Marine Ecology, University of Gothenburg, Sven Lovén Centre for Marine Sciences Kristineberg, Fiskebäckskil, Sweden.
    Martinez, K.
    Spanish National Research Council—IIQAB-CSIC, Department of Ecotechnology, Josep Pascual Vila, Barcelona, Spain .
    Blanck, H.
    Department of Plant and Environmental Sciences, University of Gothenburg, Sweden.
    Community-Level Analysis of psbA Gene Sequences and Irgarol Tolerance in Marine Periphyton2009In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 75, no 4, p. 897-906Article in journal (Refereed)
    Abstract [en]

    This study analyzes psbA gene sequences, predicted D1 protein sequences, species relative abundance, and pollution-induced community tolerance in marine periphyton communities exposed to the antifouling compound Irgarol 1051. The mechanism of action of Irgarol is the inhibition of photosynthetic electron transport at photosystem II by binding to the D1 protein. The metagenome of the communities was used to produce clone libraries containing fragments of the psbA gene encoding the D1 protein. Community tolerance was quantified with a short-term test for the inhibition of photosynthesis. The communities were established in a continuous flow of natural seawater through microcosms with or without added Irgarol. The selection pressure from Irgarol resulted in an altered species composition and an inducted community tolerance to Irgarol. Moreover, there was a very high diversity in the psbA gene sequences in the periphyton, and the composition of psbA and D1 fragments within the communities was dramatically altered by increased Irgarol exposure. Even though tolerance to this type of compound in land plants often depends on a single amino acid substitution (Ser(264)-> Gly) in the D1 protein, this was not the case for marine periphyton species. Instead, the tolerance mechanism likely involves increased degradation of D1. When we compared sequences from low and high Irgarol exposure, differences in nonconserved amino acids were found only in the so-called PEST region of D1, which is involved in regulating its degradation. Our results suggest that environmental contamination with Irgarol has led to selection for high-turnover D1 proteins in marine periphyton communities at the west coast of Sweden.

    Download full text (pdf)
    fulltext
  • 4.
    Farkas, Daniel
    et al.
    Institutionen för kemi, Göteborgs Universitet, Department of Chemistry, University of Gothenburg.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    Hansson, Örjan
    Institutionen för kemi, Göteborgs Universitet, Department of Chemistry, University of Gothenburg.
    Cloning, expression and purification of the luminal domain of spinach photosystem 1 subunit PsaF functional in binding to plastocyanin and with a disulfide bridge required for folding2011In: Protein Expression and Purification, ISSN 1046-5928, E-ISSN 1096-0279, Vol. 78, no 2, p. 156-166Article in journal (Refereed)
    Abstract [en]

    The photosystem 1 subunit PsaF is involved in the docking of the electron-donor proteins plastocyanin and cytochrome c6 in eukaryotic photosynthetic organisms. Here we report the expression, purification and basic characterization of the luminal domain of spinach PsaF, encompassing amino-acid residues 1-79. The recombinant protein was expressed in Escherichia coli BL21 (DE3) using a pET32 Xa/LIC thioredoxin fusion system. The thioredoxin fusion protein contained a His6 tag and was removed and separated from PsaF through proteolytic digestion by factor Xa followed by immobilized metal affinity chromatography. Further purification with size-exclusion chromatography resulted in a final yield of approximately 6 mg PsaF from one liter growth medium. The correct identity after the factor Xa treatment of PsaF was verified by FT-ICR mass spectrometry which also showed that the purified protein contains an intact disulfide bridge between Cys residues 6 and 38. Secondary structure and folding was further explored using far-UV CD spectroscopy indicating a α-helical content in agreement with the 3.3 Å-resolution crystal structure of photosystem I Ref. [5] and a helix-coil transition temperature of 29 °C. Thermofluorescence studies showed that the disulfide bridge is necessary to keep the overall fold of the protein and that hydrophobic regions become exposed at 50-65 °C depending on the ionic strength. The described expression and purification procedure can be used for isotopic labeling of the protein and 15N-HSQC NMR studies indicated a slow or intermediate exchange between different conformations of the prepared protein and that it belongs to the molten-globule structural family. Finally, by using a carboxyl- and amine-reactive zero-length crosslinker, we have shown that the recombinant protein binds to plastocyanin by a specific, native-like, electrostatic interaction, hence, confirming its functionality.

  • 5.
    Figueroa-Martinez, Francisco
    et al.
    Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico.
    Funes, Soledad
    Institut für Physiologische Chemie, Ludwig-Maximilians-Universität München, Germany .
    Franzén, Lars-Gunnar
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, Diego
    Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico.
    Reconstructing the mitochondrial protein import machinery of Chlamydomonas reinhardtii2008In: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 179, no 1, p. 149-155Article in journal (Refereed)
    Abstract [en]

    In Chlamydomonas reinhardtii several nucleus-encoded proteins that participate in the mitochondrial oxidative phosphorylation are targeted to the organelle by unusually long mitochondrial targeting sequences. Here, we explored the components of the mitochondrial import machinery of the green alga. We mined the algal genome, searching for yeast and plant homologs, and reconstructed the mitochondrial import machinery. All the main translocation components were identified in Chlamydomonas as well as in Arabidopsis thaliana and in the recently sequenced moss Physcomitrella patens. Some of these components appear to be duplicated, as is the case of Tim22. In contrast, several yeast components that have relatively large hydrophilic regions exposed to the cytosol or to the intermembrane space seem to be absent in land plants and green algae. If present at all, these components of plants and algae may differ significantly from their yeast counterparts. We propose that long mitochondrial targeting sequences in some Chlamydomonas mitochondrial protein precursors are involved in preventing the aggregation of the hydrophobic proteins they carry.

  • 6. Franzén, Lars-Gunnar
    Socker och hälsa – är det farligt att äta fruktos?2018In: Folkvett, ISSN 0283-0795, no 4, p. 40-61Article in journal (Other (popular science, discussion, etc.))
    Download full text (pdf)
    fulltext
  • 7.
    Funes, Soledad
    et al.
    Institut für Physiologische Chemie, Ludwig-Maximilians-Universität München, Germany.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, Diego
    Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, D.F., México.
    Chlamydomonas reinhardtii: the model of choice to study mitochondria from unicellular photosynthetic organisms.2007In: Methods in Molecular Biology, ISSN 1064-3745, Vol. 372, p. 137-149Article in journal (Other academic)
    Abstract [en]

    Chlamydomonas reinhardtii is a model organism to study photosynthesis, cellular division, flagellar biogenesis, and, more recently, mitochondrial function. It has distinct advantages in comparison to higher plants because it is unicellular, haploid, and amenable to tetrad analysis, and its three genomes are subject to specific transformation. It also has the possibility to grow either photoautotrophically or heterotrophically on acetate, making the assembly of the photosynthetic machinery not essential for cell viability. Methods developed allow the isolation of C. reinhardtii mitochondria free of thylakoid contaminants. We review the general procedures used for the biochemical characterization of mitochondria from this green alga.

  • 8.
    Liess, Antonia
    et al.
    Halmstad University, School of Business, Innovation and Sustainability.
    Barnes, Tatyana
    Sydvatten/Sweden Water Research, Research Station Bolmen, Unnaryd, Sweden,.
    Sjöstedt, Johanna
    Lund University, Lund, Sweden.
    Rankinen, Juha
    Sydvatten/Sweden Water Research, Research Station Bolmen, Unnaryd, Sweden,.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business, Innovation and Sustainability.
    Ecosystem consequences of boreal lake browning and eutrophication – using mesocoms as tools for food web studies2022In: Abstract Book: The Next Years: Sensing and Safeguarding Inland Waters, 2022, p. 111-111Conference paper (Other academic)
    Abstract [en]

    With increasing temperatures and precipitation, as well as land use changes in boreal regions, waterbodies are receiving larger inputs of coloured terrestrial humic substances. At the same time, nutrient inputs are increasing. This brownificationin combination with increasing nutrient levels has consequences for the aquatic food web in terms of species composition and energy transfer efficiency. In Lake Bolmen, Sweden’s 7ths largest lake, brownification additionally creates problems for drinkingwater production, since this lake is an important drinking water reservoir of southern Sweden. Lake monitoring data show a clear pattern of increasing brownification in Lake Bolmen over the preceding decades. To understand the consequences ofincreased browning and of increased nutrient inputs for Lake Bolmen’s food web on bacterial production, and phytoplankton and zooplankton species community composition and abundance, we conducted a 6-week mesocosm experiment during summer 2021. Brownification and nutrient ratios were manipulated. Measures of algal pigment concentrations show that browning has strong effects on algal pigment composition and thus probably on algal taxonomic composition. Our results suggest that brownification affects basic producer community composition in lakes, thus possibly changing community composition and biomass of higher trophic levels of the aquatic food web in boreal regions.

  • 9.
    Stevens, DR
    et al.
    Department of Biology, University College London, UK.
    Atteia, A
    Department of Plant Physiology, Botanical Institute, Göteborg University, Sweden.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    Purton, S
    Department of Biology, University College London, UK.
    Cycloheximide resistance conferred by novel mutations in ribosomal protein L41 of Chlamydomonas reinhardtii2001In: Molecular General Genetics, ISSN 0026-8925, E-ISSN 1432-1874, Vol. 264, no 6, p. 790-795Article in journal (Refereed)
    Abstract [en]

    Although most eukaryotic cells are sensitive to the 80S ribosome inhibitor cycloheximide (CYH), naturally occurring CYH resistance is widespread amongst yeast species. The primary determinant of resistance appears to be a single residue within ribosomal protein L41; resistance is acquired by the substitution of a conserved proline (P-56) by a glutamate residue. We have isolated the L41 gene (RPL41) from the green alga Chlamydomonas and investigated the molecular basis of CYH resistance in various mutant strains. In both the wild-type strain and the mutant act-1, a proline is found at the key position in L41.; However, analysis of six independently isolated act-2 mutants reveals that all have point mutations that replace the proline with either leucine or serine. Of the two changes, the leucine mutation confers significantly higher levels of CYH resistance. This work identifies the ACT-2 locus as RPL41 and provides a possible dominant marker for nuclear transformation of C. reinhardtii.

1 - 9 of 9
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf