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Lukáčová A, Lihanová D, Beck T, Alberty R, Vešelényiová D, Krajčovič J, Vesteg M. The Influence of Phenol on the Growth, Morphology and Cell Division of Euglena gracilis. Life (Basel) 2023; 13:1734. [PMID: 37629591 PMCID: PMC10455851 DOI: 10.3390/life13081734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/28/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
Phenol, a monocyclic aromatic hydrocarbon with various commercial uses, is a major pollutant in industrial wastewater. Euglena gracilis is a unicellular freshwater flagellate possessing secondary chloroplasts of green algal origin. This protist has been widely used for monitoring the biological effect of various inorganic and organic environmental pollutants, including aromatic hydrocarbons. In this study, we evaluate the influence of different phenol concentrations (3.39 mM, 3.81 mM, 4.23 mM, 4.65 mM, 5.07 mM, 5.49 mM and 5.91 mM) on the growth, morphology and cell division of E. gracilis. The cell count continually decreases (p < 0.05-0.001) over time with increasing phenol concentration. While phenol treatment does not induce bleaching (permanent loss of photosynthesis), the morphological changes caused by phenol include the formation of spherical (p < 0.01-0.001), hypertrophied (p < 0.05) and monster cells (p < 0.01) and lipofuscin bodies. Phenol also induces an atypical form of cell division of E. gracilis, simultaneously producing more than 2 (3-12) viable cells from a single cell. Such atypically dividing cells have a symmetric "star"-like shape. The percentage of atypically dividing cells increases (p < 0.05) with increasing phenol concentration. Our findings suggest that E. gracilis can be used as bioindicator of phenol contamination in freshwater habitats and wastewater.
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Affiliation(s)
- Alexandra Lukáčová
- Department of Biology, Ecology and Environment, Faculty of Natural Sciences, Matej Bel University, 974 01 Banská Bystrica, Slovakia (T.B.)
| | - Diana Lihanová
- Department of Biology, Ecology and Environment, Faculty of Natural Sciences, Matej Bel University, 974 01 Banská Bystrica, Slovakia (T.B.)
| | - Terézia Beck
- Department of Biology, Ecology and Environment, Faculty of Natural Sciences, Matej Bel University, 974 01 Banská Bystrica, Slovakia (T.B.)
| | - Roman Alberty
- Department of Biology, Ecology and Environment, Faculty of Natural Sciences, Matej Bel University, 974 01 Banská Bystrica, Slovakia (T.B.)
| | - Dominika Vešelényiová
- Institute of Biology and Biotechnology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, 917 01 Trnava, Slovakia
| | - Juraj Krajčovič
- Institute of Biology and Biotechnology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, 917 01 Trnava, Slovakia
| | - Matej Vesteg
- Department of Biology, Ecology and Environment, Faculty of Natural Sciences, Matej Bel University, 974 01 Banská Bystrica, Slovakia (T.B.)
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Lihanová D, Lukáčová A, Beck T, Jedlička A, Vešelényiová D, Krajčovič J, Vesteg M. Versatile biotechnological applications of Euglena gracilis. World J Microbiol Biotechnol 2023; 39:133. [PMID: 36959517 DOI: 10.1007/s11274-023-03585-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/16/2023] [Indexed: 03/25/2023]
Abstract
Euglena gracilis is a freshwater protist possessing secondary chloroplasts of green algal origin. Various physical factors (e.g. UV) and chemical compounds (e.g. antibiotics) cause the bleaching of E. gracilis cells-the loss of plastid genes leading to the permanent inability to photosynthesize. Bleaching can be prevented by antimutagens (i.e. lignin, vitamin C and selenium). Besides screening the mutagenic and antimutagenic activity of chemicals, E. gracilis is also a suitable model for studying the biological effects of many organic pollutants. Due to its capability of heavy metal sequestration, it can be used for bioremediation. E. gracilis has been successfully transformed, offering the possibility of genetic modifications for synthesizing compounds of biotechnological interest. The novel design of the "next generation" transgenic expression cassettes with respect to the specificities of euglenid gene expression is proposed. Moreover, E. gracilis is a natural source of commercially relevant bioproducts such as (pro)vitamins, wax esters, polyunsaturated fatty acids and paramylon (β-1,3-glucan). One of the highest limitations of large-scale cultivation of E. gracilis is its disability to synthesize essential vitamins B1 and B12. This disadvantage can be overcome by co-cultivation of E. gracilis with other microorganisms, which can synthesize sufficient amounts of these vitamins. Such co-cultures can be used for the effective accumulation and harvesting of Euglena biomass by bioflocculation.
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Grants
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- VEGA 1/0694/2021 Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic, and the Academy of Sciences
- ITMS 26210120024 European Regional Development Fund
- ITMS 26210120024 European Regional Development Fund
- ITMS 26210120024 European Regional Development Fund
- ITMS 26210120024 European Regional Development Fund
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Affiliation(s)
- Diana Lihanová
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 974 01, Banská Bystrica, Slovakia
| | - Alexandra Lukáčová
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 974 01, Banská Bystrica, Slovakia
| | - Terézia Beck
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 974 01, Banská Bystrica, Slovakia
| | - Andrej Jedlička
- Department of Biology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, 917 01, Trnava, Slovakia
| | - Dominika Vešelényiová
- Department of Biology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, 917 01, Trnava, Slovakia
| | - Juraj Krajčovič
- Department of Biology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, 917 01, Trnava, Slovakia
| | - Matej Vesteg
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 974 01, Banská Bystrica, Slovakia.
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Lukáčová A, Beck T, Trnková K, Trniková M, Krajčovič J, Vesteg M. Discrimination of Euglena gracilis strains Z and bacillaris by MALDI-TOF MS. J Appl Microbiol 2022; 133:930-942. [PMID: 35483969 DOI: 10.1111/jam.15600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/31/2022] [Accepted: 04/26/2022] [Indexed: 12/01/2022]
Abstract
AIMS Euglena gracilis is used as model organism for various microbiological, molecular biological and biotechnological studies. Its most studied wild type strains are Z and bacillaris, but their discrimination by standard molecular methods is difficult. Therefore, we decided to test the suitability of MALDI-TOF MS (matrix assisted laser desorption/ionization - time of flight mass spectrometry) for identification of E. gracilis and for discrimination of these two strains possessing functional chloroplasts. MALDI-TOF MS profiling was also tested for two white (non-photosynthetic) stable E. gracilis mutant strains Wgm ZOflL and W10 BSmL. METHODS AND RESULTS We have successfully obtained main spectrum profiles (MSPs) of E. gracilis strains Z, SAG 1224-5/25 and bacillaris, SAG 1224-5/15 using protein extraction procedure. Subsequent MALDI-TOF MS profiling of a number of tested samples and the comparison of the obtained protein profiles with our in-house database including MSPs of both strains has revealed that these two strains can be easily distinguished by MALDI-TOF MS based on score values over two in most cases. This method has also confirmed the ancestry of white mutant strains Wgm ZOflL and W10 BSmL, originally derived from strains Z and bacillaris, respectively. CONCLUSIONS MALDI-TOF MS is suitable, accurate and rapid method for discrimination of E. gracilis strains. SIGNIFICANCE AND IMPACT OF STUDY These results can have broad practical implications for laboratories cultivating various strains of euglenids, and they can be applied for their discrimination by MALDI-TOF MS.
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Affiliation(s)
- Alexandra Lukáčová
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Banská Bystrica, Slovakia
| | - Terézia Beck
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Banská Bystrica, Slovakia
| | - Katarína Trnková
- Department of the Environment, Faculty of Natural Sciences, Matej Bel University, Banská Bystrica, Slovakia
| | - Miriam Trniková
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Banská Bystrica, Slovakia
| | - Juraj Krajčovič
- Department of Biology, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, Trnava, Slovakia
| | - Matej Vesteg
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, Banská Bystrica, Slovakia
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Euglena gracilis can grow in the mixed culture containing Cladosporium westerdijkiae, Lysinibacillus boronitolerans and Pseudobacillus badius without the addition of vitamins B1 and B12. J Biotechnol 2022; 351:50-59. [DOI: 10.1016/j.jbiotec.2022.04.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/15/2022]
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Gain G, Vega de Luna F, Cordoba J, Perez E, Degand H, Morsomme P, Thiry M, Baurain D, Pierangelini M, Cardol P. Trophic state alters the mechanism whereby energetic coupling between photosynthesis and respiration occurs in Euglena gracilis. THE NEW PHYTOLOGIST 2021; 232:1603-1617. [PMID: 34392544 PMCID: PMC9292222 DOI: 10.1111/nph.17677] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
The coupling between mitochondrial respiration and photosynthesis plays an important role in the energetic physiology of green plants and some secondary-red photosynthetic eukaryotes (diatoms), allowing an efficient CO2 assimilation and optimal growth. Using the flagellate Euglena gracilis, we first tested if photosynthesis-respiration coupling occurs in this species harbouring secondary green plastids (i.e. originated from an endosymbiosis between a green alga and a phagotrophic euglenozoan). Second, we tested how the trophic state (mixotrophy and photoautotrophy) of the cell alters the mechanisms involved in the photosynthesis-respiration coupling. Energetic coupling between photosynthesis and respiration was determined by testing the effect of respiratory inhibitors on photosynthesis, and measuring the simultaneous variation of photosynthesis and respiration rates as a function of temperature (i.e. thermal response curves). The mechanism involved in the photosynthesis-respiration coupling was assessed by combining proteomics, biophysical and cytological analyses. Our work shows that there is photosynthesis-respiration coupling and membrane contacts between mitochondria and chloroplasts in E. gracilis. However, whereas in mixotrophy adjustment of the chloroplast ATP/NADPH ratio drives the interaction, in photoautotrophy the coupling is conditioned by CO2 limitation and photorespiration. This indicates that maintenance of photosynthesis-respiration coupling, through plastic metabolic responses, is key to E. gracilis functioning under changing environmental conditions.
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Affiliation(s)
- Gwenaëlle Gain
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
| | - Félix Vega de Luna
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
| | - Javier Cordoba
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
| | - Emilie Perez
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
| | - Hervé Degand
- Louvain Institute of Biomolecular Science and Technology (LIBST)UCLouvainLouvain‐la‐NeuveB‐1348Belgium
| | - Pierre Morsomme
- Louvain Institute of Biomolecular Science and Technology (LIBST)UCLouvainLouvain‐la‐NeuveB‐1348Belgium
| | - Marc Thiry
- Laboratoire de Biologie Cellulaire et TissulaireGiga‐NeurosciencesULiègeLiègeB‐4000Belgium
| | - Denis Baurain
- InBioS – PhytoSYSTEMSEukaryotic PhylogenomicsULiègeLiègeB‐4000Belgium
| | - Mattia Pierangelini
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
| | - Pierre Cardol
- InBioS – PhytoSYSTEMSLaboratoire de Génétique et Physiologie des MicroalguesULiègeLiègeB‐4000Belgium
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Miranda-Astudillo HV, Yadav KNS, Boekema EJ, Cardol P. Supramolecular associations between atypical oxidative phosphorylation complexes of Euglena gracilis. J Bioenerg Biomembr 2021; 53:351-363. [PMID: 33646522 PMCID: PMC8124061 DOI: 10.1007/s10863-021-09882-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/11/2021] [Indexed: 11/28/2022]
Abstract
In vivo associations of respiratory complexes forming higher supramolecular structures are generally accepted nowadays. Supercomplexes (SC) built by complexes I, III and IV and the so-called respirasome (I/III2/IV) have been described in mitochondria from several model organisms (yeasts, mammals and green plants), but information is scarce in other lineages. Here we studied the supramolecular associations between the complexes I, III, IV and V from the secondary photosynthetic flagellate Euglena gracilis with an approach that involves the extraction with several mild detergents followed by native electrophoresis. Despite the presence of atypical subunit composition and additional structural domains described in Euglena complexes I, IV and V, canonical associations into III2/IV, III2/IV2 SCs and I/III2/IV respirasome were observed together with two oligomeric forms of the ATP synthase (V2 and V4). Among them, III2/IV SC could be observed by electron microscopy. The respirasome was further purified by two-step liquid chromatography and showed in-vitro oxygen consumption independent of the addition of external cytochrome c.
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Affiliation(s)
- H V Miranda-Astudillo
- InBios/Phytosystems, Institut de Botanique, University of Liège, Liège, Belgium.
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.
| | - K N S Yadav
- Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
- School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - E J Boekema
- Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
| | - P Cardol
- InBios/Phytosystems, Institut de Botanique, University of Liège, Liège, Belgium.
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Vesteg M, Hadariová L, Horváth A, Estraño CE, Schwartzbach SD, Krajčovič J. Comparative molecular cell biology of phototrophic euglenids and parasitic trypanosomatids sheds light on the ancestor of Euglenozoa. Biol Rev Camb Philos Soc 2019; 94:1701-1721. [PMID: 31095885 DOI: 10.1111/brv.12523] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 01/23/2023]
Abstract
Parasitic trypanosomatids and phototrophic euglenids are among the most extensively studied euglenozoans. The phototrophic euglenid lineage arose relatively recently through secondary endosymbiosis between a phagotrophic euglenid and a prasinophyte green alga that evolved into the euglenid secondary chloroplast. The parasitic trypanosomatids (i.e. Trypanosoma spp. and Leishmania spp.) and the freshwater phototrophic euglenids (i.e. Euglena gracilis) are the most evolutionary distant lineages in the Euglenozoa phylogenetic tree. The molecular and cell biological traits they share can thus be considered as ancestral traits originating in the common euglenozoan ancestor. These euglenozoan ancestral traits include common mitochondrial presequence motifs, respiratory chain complexes containing various unique subunits, a unique ATP synthase structure, the absence of mitochondria-encoded transfer RNAs (tRNAs), a nucleus with a centrally positioned nucleolus, closed mitosis without dissolution of the nuclear membrane and nucleoli, a nuclear genome containing the unusual 'J' base (β-D-glucosyl-hydroxymethyluracil), processing of nucleus-encoded precursor messenger RNAs (pre-mRNAs) via spliced-leader RNA (SL-RNA) trans-splicing, post-transcriptional gene silencing by the RNA interference (RNAi) pathway and the absence of transcriptional regulation of nuclear gene expression. Mitochondrial uridine insertion/deletion RNA editing directed by guide RNAs (gRNAs) evolved in the ancestor of the kinetoplastid lineage. The evolutionary origin of other molecular features known to be present only in either kinetoplastids (i.e. polycistronic transcripts, compaction of nuclear genomes) or euglenids (i.e. monocistronic transcripts, huge genomes, many nuclear cis-spliced introns, polyproteins) is unclear.
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Affiliation(s)
- Matej Vesteg
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, 974 01, Banská Bystrica, Slovakia
| | - Lucia Hadariová
- Biotechnology and Biomedicine Center of the Academy of Sciences and Charles University in Vestec (BIOCEV), 252 50, Vestec, Czech Republic.,Department of Parasitology, Faculty of Science, Charles University in Prague, 128 44, Prague, Czech Republic
| | - Anton Horváth
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, 842 15, Bratislava, Slovakia
| | - Carlos E Estraño
- Department of Biological Sciences, University of Memphis, Memphis, TN, 38152-3560, USA
| | - Steven D Schwartzbach
- Department of Biological Sciences, University of Memphis, Memphis, TN, 38152-3560, USA
| | - Juraj Krajčovič
- Department of Biology, Faculty of Natural Sciences, University of ss. Cyril and Methodius, 917 01, Trnava, Slovakia
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Zimorski V, Rauch C, van Hellemond JJ, Tielens AGM, Martin WF. The Mitochondrion of Euglena gracilis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:19-37. [PMID: 28429315 DOI: 10.1007/978-3-319-54910-1_2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In the presence of oxygen, Euglena gracilis mitochondria function much like mammalian mitochondria. Under anaerobiosis, E. gracilis mitochondria perform a malonyl-CoA independent synthesis of fatty acids leading to accumulation of wax esters, which serve as the sink for electrons stemming from glycolytic ATP synthesis and pyruvate oxidation. Some components (enzymes and cofactors) of Euglena's anaerobic energy metabolism are found among the anaerobic mitochondria of invertebrates, others are found among hydrogenosomes, the H2-producing anaerobic mitochondria of protists.
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Affiliation(s)
- Verena Zimorski
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Cessa Rauch
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Jaap J van Hellemond
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Aloysius G M Tielens
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands.,Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - William F Martin
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
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Hadariová L, Vesteg M, Birčák E, Schwartzbach SD, Krajčovič J. An intact plastid genome is essential for the survival of colorless Euglena longa but not Euglena gracilis. Curr Genet 2016; 63:331-341. [PMID: 27553633 DOI: 10.1007/s00294-016-0641-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 08/02/2016] [Accepted: 08/13/2016] [Indexed: 12/18/2022]
Abstract
Euglena gracilis growth with antibacterial agents leads to bleaching, permanent plastid gene loss. Colorless Euglena (Astasia) longa resembles a bleached E. gracilis. To evaluate the role of bleaching in E. longa evolution, the effect of streptomycin, a plastid protein synthesis inhibitor, and ofloxacin, a plastid DNA gyrase inhibitor, on E. gracilis and E. longa growth and plastid DNA content were compared. E. gracilis growth was unaffected by streptomycin and ofloxacin. Quantitative PCR analyses revealed a time dependent loss of plastid genes in E. gracilis demonstrating that bleaching agents produce plastid gene deletions without affecting cell growth. Streptomycin and ofloxacin inhibited E. longa growth indicating that it requires plastid genes to survive. This suggests that evolutionary divergence of E. longa from E. gracilis was triggered by the loss of a cytoplasmic metabolic activity also occurring in the plastid. Plastid metabolism has become obligatory for E. longa cell growth. A process termed "intermittent bleaching", short term exposure to subsaturating concentrations of reversible bleaching agents followed by growth in the absence of a bleaching agent, is proposed as the molecular mechanism for E. longa plastid genome reduction. Various non-photosynthetic lineages could have independently arisen from their photosynthetic ancestors via a similar process.
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Affiliation(s)
- Lucia Hadariová
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina G-1, 842 15, Bratislava, Slovak Republic
| | - Matej Vesteg
- Department of Biology and Ecology, Faculty of Natural Sciences, Matej Bel University, 974 01, Banská Bystrica, Slovakia
| | - Erik Birčák
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina G-1, 842 15, Bratislava, Slovak Republic
| | | | - Juraj Krajčovič
- Department of Genetics, Faculty of Natural Sciences, Comenius University, Mlynská dolina G-1, 842 15, Bratislava, Slovak Republic. .,Department of Biology, Faculty of Natural Sciences, University of ss. Cyril and Methodius, 917 01, Trnava, Slovakia.
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Dobáková E, Flegontov P, Skalický T, Lukeš J. Unexpectedly Streamlined Mitochondrial Genome of the Euglenozoan Euglena gracilis. Genome Biol Evol 2015; 7:3358-67. [PMID: 26590215 PMCID: PMC4700960 DOI: 10.1093/gbe/evv229] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2015] [Indexed: 11/29/2022] Open
Abstract
In this study, we describe the mitochondrial genome of the excavate flagellate Euglena gracilis. Its gene complement is reduced as compared with the well-studied sister groups Diplonemea and Kinetoplastea. We have identified seven protein-coding genes: Three subunits of respiratory complex I (nad1, nad4, and nad5), one subunit of complex III (cob), and three subunits of complex IV (cox1, cox2, and a highly divergent cox3). Moreover, fragments of ribosomal RNA genes have also been identified. Genes encoding subunits of complex V, ribosomal proteins and tRNAs were missing, and are likely located in the nuclear genome. Although mitochondrial genomes of diplonemids and kinetoplastids possess the most complex RNA processing machineries known, including trans-splicing and editing of the uridine insertion/deletion type, respectively, our transcriptomic data suggest their total absence in E. gracilis. This finding supports a scenario in which the complex mitochondrial processing machineries of both sister groups evolved relatively late in evolution from a streamlined genome and transcriptome of their common predecessor.
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Affiliation(s)
- Eva Dobáková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic Departments of Biochemistry and Genetics, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Pavel Flegontov
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Tomáš Skalický
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic Canadian Institute for Advanced Research, Toronto, Ontario, Canada
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