1
|
Madireddi SK, Yadav RM, Zamal MY, Bag P, Gunasekaran JX, Subramanyam R. Exploring LHCSR3 expression and its role in Chlamydomonas reinhardtii under osmotic stress: Implications for non-photochemical quenching mechanism. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2024; 256:112941. [PMID: 38763078 DOI: 10.1016/j.jphotobiol.2024.112941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/02/2024] [Accepted: 05/13/2024] [Indexed: 05/21/2024]
Abstract
Plants have a protective mechanism called non-photochemical quenching to prevent damage caused by excessive sunlight. A critical component of this mechanism is energy-dependent quenching (qE). In Chlamydomonas reinhardtii, the protein expression called light-harvesting complex stress-related protein 3 (LHCSR3) is crucial for the qE mechanism. LHCSR3 expression is observed in various conditions that result in photooxidation, such as exposure to high light or nutrient deprivation, where the amount of captured light surpasses the maximum photosynthetic capacity. Although the role of LHCSR3 has been extensively studied under high light (HL) conditions, its function during nutrient starvation remains unclear. In this study, we demonstrate that LHCSR3 expression can occur under light intensities below saturation without triggering qE, particularly when nutrients are limited. To investigate this, we cultivated C. reinhardtii cells under osmotic stress, which replicates conditions of nutrient scarcity. Furthermore, we examined the photosynthetic membrane complexes of wild-type (WT) and npq4 mutant strains grown under osmotic stress. Our analysis revealed that LHCSR3 expression might modify the interaction between the photosystem II core and its peripheral light-harvesting complex II antennae. This alteration could potentially impede the transfer of excitation energy from the antenna to the reaction center.
Collapse
Affiliation(s)
- Sai Kiran Madireddi
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Ranay Mohan Yadav
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Mohammad Yusuf Zamal
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Pushan Bag
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Jerome Xavier Gunasekaran
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Rajagopal Subramanyam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| |
Collapse
|
2
|
Esteves SM, Jadoul A, Iacono F, Schloesser M, Bosman B, Carnol M, Druet T, Cardol P, Hanikenne M. Natural variation of nutrient homeostasis among laboratory and field strains of Chlamydomonas reinhardtii. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:5198-5217. [PMID: 37235689 DOI: 10.1093/jxb/erad194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 05/24/2023] [Indexed: 05/28/2023]
Abstract
Natural variation among individuals and populations exists in all species, playing key roles in response to environmental stress and adaptation. Micro- and macronutrients have a wide range of functions in photosynthetic organisms, and mineral nutrition thus plays a sizable role in biomass production. To maintain nutrient concentrations inside the cell within physiological limits and prevent the detrimental effects of deficiency or excess, complex homeostatic networks have evolved in photosynthetic cells. The microalga Chlamydomonas reinhardtii (Chlamydomonas) is a unicellular eukaryotic model for studying such mechanisms. In this work, 24 Chlamydomonas strains, comprising field isolates and laboratory strains, were examined for intraspecific differences in nutrient homeostasis. Growth and mineral content were quantified in mixotrophy, as full nutrition control, and compared with autotrophy and nine deficiency conditions for macronutrients (-Ca, -Mg, -N, -P, and -S) and micronutrients (-Cu, -Fe, -Mn, and -Zn). Growth differences among strains were relatively limited. However, similar growth was accompanied by highly divergent mineral accumulation among strains. The expression of nutrient status marker genes and photosynthesis were scored in pairs of contrasting field strains, revealing distinct transcriptional regulation and nutrient requirements. Leveraging this natural variation should enable a better understanding of nutrient homeostasis in Chlamydomonas.
Collapse
Affiliation(s)
- Sara M Esteves
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, Belgium
| | - Alice Jadoul
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, Belgium
| | - Fabrizio Iacono
- InBioS-PhytoSystems, Genetics and Physiology of Microalgae, University of Liège, Belgium
| | - Marie Schloesser
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, Belgium
| | - Bernard Bosman
- InBioS-PhytoSystems, Laboratory of Plant and Microbial Ecology, University of Liège, Belgium
| | - Monique Carnol
- InBioS-PhytoSystems, Laboratory of Plant and Microbial Ecology, University of Liège, Belgium
| | - Tom Druet
- Unit of Animal Genomics (GIGA), University of Liège, Belgium
| | - Pierre Cardol
- InBioS-PhytoSystems, Genetics and Physiology of Microalgae, University of Liège, Belgium
| | - Marc Hanikenne
- InBioS-PhytoSystems, Translational Plant Biology, University of Liège, Belgium
| |
Collapse
|
3
|
Schmollinger S, Chen S, Merchant SS. Quantitative elemental imaging in eukaryotic algae. Metallomics 2023; 15:mfad025. [PMID: 37186252 PMCID: PMC10209819 DOI: 10.1093/mtomcs/mfad025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/03/2023] [Indexed: 05/17/2023]
Abstract
All organisms, fundamentally, are made from the same raw material, namely the elements of the periodic table. Biochemical diversity is achieved by how these elements are utilized, for what purpose, and in which physical location. Determining elemental distributions, especially those of trace elements that facilitate metabolism as cofactors in the active centers of essential enzymes, can determine the state of metabolism, the nutritional status, or the developmental stage of an organism. Photosynthetic eukaryotes, especially algae, are excellent subjects for quantitative analysis of elemental distribution. These microbes utilize unique metabolic pathways that require various trace nutrients at their core to enable their operation. Photosynthetic microbes also have important environmental roles as primary producers in habitats with limited nutrient supplies or toxin contaminations. Accordingly, photosynthetic eukaryotes are of great interest for biotechnological exploitation, carbon sequestration, and bioremediation, with many of the applications involving various trace elements and consequently affecting their quota and intracellular distribution. A number of diverse applications were developed for elemental imaging, allowing subcellular resolution, with X-ray fluorescence microscopy (XFM, XRF) being at the forefront, enabling quantitative descriptions of intact cells in a non-destructive method. This Tutorial Review summarizes the workflow of a quantitative, single-cell elemental distribution analysis of a eukaryotic alga using XFM.
Collapse
Affiliation(s)
- Stefan Schmollinger
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA
- Departments of Molecular and Cell Biology and Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Si Chen
- X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Sabeeha S Merchant
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA 94720, USA
- Departments of Molecular and Cell Biology and Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| |
Collapse
|
4
|
Glaesener AG, Merchant SS. Optimizing Fe Nutrition for Algal Growth. Methods Mol Biol 2023; 2665:203-215. [PMID: 37166603 DOI: 10.1007/978-1-0716-3183-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Chlamydomonas is an excellent reference system for dissecting the impact of iron (Fe) nutrition on photosynthetic and other metabolisms. The operational definition of four stages of Fe nutrition is described and a guide to the practical use of these stages is offered, specifically the preparation of media and growth of mixotrophic cultures. A key consideration is the impact of carbon metabolism on the expression of Fe-containing enzymes and hence the Fe quota. The absolute concentration of Fe in the medium is less determinative of gene expression than the Fe available on a per-cell basis. In nature, algal cells may transition from Fe-replete to -deficient to -limited during a bloom.
Collapse
Affiliation(s)
- Anne G Glaesener
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, USA
| | - Sabeeha S Merchant
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
- Lawrence Livermore National Laboratory, Physical and Life Science Directorate, Livermore, CA, USA.
| |
Collapse
|
5
|
Influence of Food Waste and Graphene Oxide Nanosheets on Monoraphidium sp. VV1 Biomass and Biodiesel Production. Top Catal 2022. [DOI: 10.1007/s11244-022-01755-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
6
|
Kochoni E, Doose C, Gonzalez P, Fortin C. Role of iron in gene expression and in the modulation of copper uptake in a freshwater alga: Insights on Cu and Fe assimilation pathways. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 305:119311. [PMID: 35439593 DOI: 10.1016/j.envpol.2022.119311] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/21/2022] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
Metal uptake and toxicity can generally be related to its aqueous speciation and to the presence of competitive ions as described by the biotic ligand model. Beyond these simple chemical interactions at the surface of aquatic organisms, several internal biological feedback mechanisms can also modulate metal uptake. This is particularly important for essential elements for which specific transport systems were developed over the course of evolution. Based on the results of short-term Cu2+ uptake experiments and on the analysis of the expression of certain genes involved in Cu and Fe homeostasis, we studied the effects of Fe3+ on Cu2+ uptake by the freshwater green alga Chlamydomonas reinhardtii. We observed a significant increase in Cu2+ uptake rate in algal cells acclimated to a low Fe3+ medium up to 4.7 times greater compared to non-acclimated algal cells. The overexpression of the ferroxidase FOX1 and permease FTR1 genes suggests an activation of the high affinity Fe3+ assimilation system, which could constitute a plausible explanation for the increase in Cu2+ uptake rate in acclimatized algae. We show that Fe availability can have a significant impact on Cu uptake. Our observations reinforce the importance of considering physiological factors to better predict metal bioavailability.
Collapse
Affiliation(s)
- Emeric Kochoni
- EcotoQ, Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC, G1K 9A9, Canada
| | - Caroline Doose
- Laboratoire de Biologie des Organismes et des écosystèmes Aquatiques, Muséum National d'Histoire Naturelle, Station Marine Concarneau, 29900, Concarneau, France
| | - Patrice Gonzalez
- Université de Bordeaux, CNRS, EPOC, EPHE, UMR 5805, 33600, Pessac, France
| | - Claude Fortin
- EcotoQ, Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC, G1K 9A9, Canada.
| |
Collapse
|
7
|
Abinandan S, Venkateswarlu K, Megharaj M. Phenotypic changes in microalgae at acidic pH mediate their tolerance to higher concentrations of transition metals. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 2:100081. [PMID: 35028626 PMCID: PMC8714768 DOI: 10.1016/j.crmicr.2021.100081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/22/2021] [Accepted: 11/06/2021] [Indexed: 11/25/2022] Open
Abstract
Acid-tolerant microalgae were grown at pH 3.5 and 6.7 in presence of heavy metals (HMs). HMs-induced phenotypic changes in microalgae were evaluated by ATR-FTIR spectroscopy. Higher HMs bioavailability affected microalgae more at pH 6.7 than pH 3.5. Acclimation of microalgal strains to acidic pH significantly alleviates HMs toxicity.
Acclimatory phenotypic response is a common phenomenon in microalgae, particularly during heavy metal stress. It is not clear so far whether acclimating to one abiotic stressor can alleviate the stress imposed by another abiotic factor. The intent of the present study was to demonstrate the implication of acidic pH in effecting phenotypic changes that facilitate microalgal tolerance to biologically excess concentrations of heavy metals. Two microalgal strains, Desmodesmus sp. MAS1 and Heterochlorella sp. MAS3, were exposed to biologically excess concentrations of Cu (0.50 and 1.0 mg L‒1), Fe (5 and 10 mg L‒1), Mn (5 and 10 mg L‒1) and Zn (2, 5 and 10 mg L‒1) supplemented to the culture medium at pH 3.5 and 6.7. Chlorophyll autofluorescence and biochemical fingerprinting using FTIR-spectroscopy were used to assess the microalgal strains for phenotypic changes that mediate tolerance to metals. Both the strains responded to acidic pH by effecting differential changes in biochemicals such as carbohydrates, proteins, and lipids. Both the microalgal strains, when acclimated to low pH of 3.5, exhibited an increase in protein (< 2-fold) and lipid (> 1.5-fold). Strain MAS1 grown at pH 3.5 showed a reduction (1.5-fold) in carbohydrates while strain MAS3 exhibited a 17-fold increase in carbohydrates as compared to their growth at pH 6.7. However, lower levels of biologically excess concentrations of the selected transition metals at pH 6.7 unveiled positive or no effect on physiology and biochemistry in microalgal strains, whereas growth with higher metal concentrations at this pH resulted in decreased chlorophyll content. Although the bioavailability of free-metal ions is higher at pH 3.5, as revealed by Visual MINTEQ model, no adverse effect was observed on chlorophyll content in cells grown at pH 3.5 than at pH 6.7. Furthermore, increasing concentrations of Fe, Mn and Zn significantly upregulated the carbohydrate metabolism, but not protein and lipid synthesis, in both strains at pH 3.5 as compared to their growth at pH 6.7. Overall, the impact of pH 3.5 on growth response suggested that acclimation of microalgal strains to acidic pH alleviates metal toxicity by triggering physiological and biochemical changes in microalgae for their survival.
Collapse
Affiliation(s)
- Sudharsanam Abinandan
- Global Centre for Environmental Remediation (GCER), College of Engineering, Science and Environment, The University of Newcastle, ATC Building, University Drive, Callaghan, NSW 2308, Australia
| | - Kadiyala Venkateswarlu
- Formerly Department of Microbiology, Sri Krishnadevaraya University, Anantapuramu, 515003, India
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation (GCER), College of Engineering, Science and Environment, The University of Newcastle, ATC Building, University Drive, Callaghan, NSW 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), The University of Newcastle, Callaghan, NSW 2308, Australia
- Corresponding author at: Global Centre for Environmental Remediation (GCER), College of Engineering, Science and Environment, The University of Newcastle, ATC Building, University Drive, Callaghan, NSW 2308, Australia.
| |
Collapse
|
8
|
Augmenting the expression of accD and rbcL genes using optimized iron concentration to achieve higher biomass and biodiesel in Chlorella vulgaris. Biotechnol Lett 2020; 42:2631-2641. [PMID: 32720070 DOI: 10.1007/s10529-020-02973-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Accepted: 07/16/2020] [Indexed: 12/16/2022]
Abstract
Chlorella vulgaris is a form of microalgae commonly employed as a biological source of oil for biodiesel production. Major algal cultivation strategies are focused on stimulating growth rate and lipid content. In the present study, the algal growth media was supplemented with iron (III) chloride (FeCl3), as a stimulating factor for growth and lipid production, in three iron concentrations including 90, 200, and 500 µM. The turbidity of algal cells was measured on different days, to determine the growth rate. In optimum iron concentration, this measurement experienced a 2.1-fold increase. Next, the lipid content was extracted, and the amount of lipid produced in each treatment was calculated, which demonstrated a 4.57-fold increase in lipid productivity. The expression of genes corresponding to the metabolic enzymes (i.e. acetyl-CoA carboxylase (accD) and ribulose bisphosphate carboxylase large chain (rbcL)) was evaluated using real-time PCR under different initial iron feeds. As demonstrated in the results, the initial iron feed of 90 µM was an optimum concentration that obtained the highest growth rate, more cell density, and increased lipid production. In 90 µM initial iron concentration, the expression of accD and rbcL genes showed a 4.8- and 35-fold increase, respectively, compared to that of the control genes. Based on the results, this optimum iron concentration could satisfy the industrial interest in biodiesel production from C. vulgaris as a potential stimulating factor. However, higher levels of iron (e.g. 200 and 500 µM) failed to act as positive stress for increasing biodiesel production. Finally, in this paper, different mechanisms where iron affects acetyl-CoA carboxylase (ACCase) and 1,5-ribulose bisphosphate carboxylase/oxygenase (RuBisCo) are illustrated.
Collapse
|
9
|
Zheng Y, Xue C, Chen H, He C, Wang Q. Low-Temperature Adaptation of the Snow Alga Chlamydomonas nivalis Is Associated With the Photosynthetic System Regulatory Process. Front Microbiol 2020; 11:1233. [PMID: 32587584 PMCID: PMC7297934 DOI: 10.3389/fmicb.2020.01233] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 05/14/2020] [Indexed: 12/28/2022] Open
Abstract
The alga Chlamydomonas nivalis thrives in polar snow fields and on high-altitude mountain tops, and contributes significantly on primary production in the polar regions, however, the mechanisms underlying this adaptation to low temperatures are unknown. Here, we compared the growth, photosynthetic activity, membrane lipid peroxidation, and antioxidant activity of C. nivalis with those of the model alga C. reinhardtii, under grow temperature and low temperatures. C. nivalis maintained its photosynthetic activity in these conditions by reducing the light-harvesting ability of photosystem II and enhancing the cyclic electron transfer around photosystem I, both of which limited damage to the photosystem from excess light energy and resulted in ATP production, supporting cellular growth and other physiological processes. Furthermore, the increased cyclic electron transfer rate, carotenoid content, and antioxidant enzyme activities jointly regulated the reactive oxygen species levels in C. nivalis, enabling recovery from excess excitation energy and reduced photooxidative damage to the cell. Therefore, we propose a model in which adaptive mechanisms related to photosynthetic regulation promote the survival and even blooming of C. nivalis under polar environment, suggesting that C. nivalis can provide organic carbon sources as an important primary producer for other surrounding life in the polar regions for maintaining ecosystem.
Collapse
Affiliation(s)
- Yanli Zheng
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chunling Xue
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Hui Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Chenliu He
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qiang Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
| |
Collapse
|
10
|
Kroh GE, Pilon M. Regulation of Iron Homeostasis and Use in Chloroplasts. Int J Mol Sci 2020; 21:E3395. [PMID: 32403383 PMCID: PMC7247011 DOI: 10.3390/ijms21093395] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/08/2020] [Accepted: 05/09/2020] [Indexed: 01/20/2023] Open
Abstract
Iron (Fe) is essential for life because of its role in protein cofactors. Photosynthesis, in particular photosynthetic electron transport, has a very high demand for Fe cofactors. Fe is commonly limiting in the environment, and therefore photosynthetic organisms must acclimate to Fe availability and avoid stress associated with Fe deficiency. In plants, adjustment of metabolism, of Fe utilization, and gene expression, is especially important in the chloroplasts during Fe limitation. In this review, we discuss Fe use, Fe transport, and mechanisms of acclimation to Fe limitation in photosynthetic lineages with a focus on the photosynthetic electron transport chain. We compare Fe homeostasis in Cyanobacteria, the evolutionary ancestors of chloroplasts, with Fe homeostasis in green algae and in land plants in order to provide a deeper understanding of how chloroplasts and photosynthesis may cope with Fe limitation.
Collapse
Affiliation(s)
| | - Marinus Pilon
- Department of Biology, Colorado State University Department of Biology, Fort Collins, CO 80523, USA;
| |
Collapse
|
11
|
Munz J, Xiong Y, Kim JYH, Sung YJ, Seo S, Hong RH, Kariyawasam T, Shelley N, Lee J, Sim SJ, Jin E, Lee JH. Arginine-fed cultures generates triacylglycerol by triggering nitrogen starvation responses during robust growth in Chlamydomonas. ALGAL RES 2020. [DOI: 10.1016/j.algal.2019.101782] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
12
|
Metabolic, Physiological, and Transcriptomics Analysis of Batch Cultures of the Green Microalga Chlamydomonas Grown on Different Acetate Concentrations. Cells 2019; 8:cells8111367. [PMID: 31683711 PMCID: PMC6912441 DOI: 10.3390/cells8111367] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 10/23/2019] [Accepted: 10/30/2019] [Indexed: 01/13/2023] Open
Abstract
Acetate can be efficiently metabolized by the green microalga Chlamydomonas reinhardtii. The regular concentration is 17 mM, although higher concentrations are reported to increase starch and fatty acid content. To understand the responses to higher acetate concentrations, Chlamydomonas cells were cultivated in batch mode in the light at 17, 31, 44, and 57 mM acetate. Metabolic analyses show that cells grown at 57 mM acetate possess increased contents of all components analyzed (starch, chlorophylls, fatty acids, and proteins), with a three-fold increased volumetric biomass yield compared to cells cultivated at 17 mM acetate at the entry of stationary phase. Physiological analyses highlight the importance of photosynthesis for the low-acetate and exponential-phase samples. The stationary phase is reached when acetate is depleted, except for the cells grown at 57 mM acetate, which still divide until ammonium exhaustion. Surprisal analysis of the transcriptomics data supports the biological significance of our experiments. This allows the establishment of a model for acetate assimilation, its transcriptional regulation and the identification of candidates for genetic engineering of this metabolic pathway. Altogether, our analyses suggest that growing at high-acetate concentrations could increase biomass productivities in low-light and CO2-limiting air-bubbled medium for biotechnology.
Collapse
|
13
|
Tsednee M, Castruita M, Salomé PA, Sharma A, Lewis BE, Schmollinger SR, Strenkert D, Holbrook K, Otegui MS, Khatua K, Das S, Datta A, Chen S, Ramon C, Ralle M, Weber PK, Stemmler TL, Pett-Ridge J, Hoffman BM, Merchant SS. Manganese co-localizes with calcium and phosphorus in Chlamydomonas acidocalcisomes and is mobilized in manganese-deficient conditions. J Biol Chem 2019; 294:17626-17641. [PMID: 31527081 DOI: 10.1074/jbc.ra119.009130] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 09/09/2019] [Indexed: 12/27/2022] Open
Abstract
Exposing cells to excess metal concentrations well beyond the cellular quota is a powerful tool for understanding the molecular mechanisms of metal homeostasis. Such improved understanding may enable bioengineering of organisms with improved nutrition and bioremediation capacity. We report here that Chlamydomonas reinhardtii can accumulate manganese (Mn) in proportion to extracellular supply, up to 30-fold greater than its typical quota and with remarkable tolerance. As visualized by X-ray fluorescence microscopy and nanoscale secondary ion MS (nanoSIMS), Mn largely co-localizes with phosphorus (P) and calcium (Ca), consistent with the Mn-accumulating site being an acidic vacuole, known as the acidocalcisome. Vacuolar Mn stores are accessible reserves that can be mobilized in Mn-deficient conditions to support algal growth. We noted that Mn accumulation depends on cellular polyphosphate (polyP) content, indicated by 1) a consistent failure of C. reinhardtii vtc1 mutant strains, which are deficient in polyphosphate synthesis, to accumulate Mn and 2) a drastic reduction of the Mn storage capacity in P-deficient cells. Rather surprisingly, X-ray absorption spectroscopy, EPR, and electron nuclear double resonance revealed that only little Mn2+ is stably complexed with polyP, indicating that polyP is not the final Mn ligand. We propose that polyPs are a critical component of Mn accumulation in Chlamydomonas by driving Mn relocation from the cytosol to acidocalcisomes. Within these structures, polyP may, in turn, escort vacuolar Mn to a number of storage ligands, including phosphate and phytate, and other, yet unidentified, compounds.
Collapse
Affiliation(s)
| | - Madeli Castruita
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - Patrice A Salomé
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095.,Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095
| | - Ajay Sharma
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208
| | - Brianne E Lewis
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48201
| | - Stefan R Schmollinger
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095.,Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095
| | - Daniela Strenkert
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095.,Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095
| | - Kristen Holbrook
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095
| | - Marisa S Otegui
- Departments of Botany and Genetics, University of Wisconsin, Madison, Wisconsin 53706
| | - Kaustav Khatua
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Sayani Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Ankona Datta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Si Chen
- Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439
| | - Christina Ramon
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550
| | - Martina Ralle
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239
| | - Peter K Weber
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550
| | - Timothy L Stemmler
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48201
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208
| | - Sabeeha S Merchant
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, California 90095 .,Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095
| |
Collapse
|
14
|
Gasulla F, Casano L, Guéra A. Chlororespiration induces non-photochemical quenching of chlorophyll fluorescence during darkness in lichen chlorobionts. PHYSIOLOGIA PLANTARUM 2019; 166:538-552. [PMID: 29952012 DOI: 10.1111/ppl.12792] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 06/15/2018] [Accepted: 06/19/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Francisco Gasulla
- Departamento de Ciencias de la Vida, Universidad de Alcalá, Edificio de Ciencias, Campus Científico-Tecnológico (Externo), 28802, Alcalá de Henares (Madrid), Spain
| | - Leonardo Casano
- Departamento de Ciencias de la Vida, Universidad de Alcalá, Edificio de Ciencias, Campus Científico-Tecnológico (Externo), 28802, Alcalá de Henares (Madrid), Spain
| | - Alfredo Guéra
- Departamento de Ciencias de la Vida, Universidad de Alcalá, Edificio de Ciencias, Campus Científico-Tecnológico (Externo), 28802, Alcalá de Henares (Madrid), Spain
| |
Collapse
|
15
|
Devadasu E, Chinthapalli DK, Chouhan N, Madireddi SK, Rasineni GK, Sripadi P, Subramanyam R. Changes in the photosynthetic apparatus and lipid droplet formation in Chlamydomonas reinhardtii under iron deficiency. PHOTOSYNTHESIS RESEARCH 2019; 139:253-266. [PMID: 30218258 DOI: 10.1007/s11120-018-0580-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Accepted: 08/28/2018] [Indexed: 05/19/2023]
Abstract
The unicellular photosynthetic alga Chlamydomonas reinhardtii was propagated in iron deficiency medium and patterns of growth, photosynthetic efficiency, lipid accumulation, as well as the expression of lipid biosynthetic and photosynthesis-related proteins were analysed and compared with iron-sufficient growth conditions. As expected, the photosynthetic rate was reduced (maximally after 4 days of growth) as a result of increased non-photochemical quenching (NPQ). Surprisingly, the stress-response protein LHCSR3 was expressed in conditions of iron deficiency that cause NPQ induction. In addition, the protein contents of both the PSI and PSII reaction centres were gradually reduced during growth in iron deficiency medium. Interestingly, the two generations of Fe deficiency cells could be able to recover the photosynthesis but the second generation cells recovered much slower as these cells were severely in shock. Analysis by flow cytometry with fluorescence-activated cell sorting and thin layer chromatography showed that iron deficiency also induced the accumulation of triacylglycerides (TAG), which resulted in the formation of lipid droplets. This was most significant between 48 and 72 h of growth. Dramatic increases in DGAT2A and PDAT1 levels were caused by iron starvation, which indicated that the biosynthesis of TAG had been increased. Analysis using gas chromatography mass spectrometry showed that levels of 16:0, 18:0, 18:2 and 18:3Δ9,12,15 fatty acids were significantly elevated. The results of this study highlight the genes/enzymes of Chlamydomonas that affect lipid synthesis through their influence on photosynthesis, and these represent potential targets of metabolic engineering to develop strains for biofuel production.
Collapse
Affiliation(s)
- Elsinraju Devadasu
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India
| | - Dinesh Kumar Chinthapalli
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India
- Analytical Chemistry and Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India
| | - Nisha Chouhan
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India
| | - Sai Kiran Madireddi
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India
| | - Girish Kumar Rasineni
- Center for Excellence in Medical Services Pvt. Ltd., Kineta Towers, Road No. 3, Banjara Hills, Hyderabad, Telangana, 500034, India
| | - Prabhakar Sripadi
- Analytical Chemistry and Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500 007, India
| | - Rajagopal Subramanyam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India.
| |
Collapse
|
16
|
Luo Q, Song W, Li Y, Wang C, Hu Z. Flagella-Associated WDR-Containing Protein CrFAP89 Regulates Growth and Lipid Accumulation in Chlamydomonas reinhardtii. FRONTIERS IN PLANT SCIENCE 2018; 9:691. [PMID: 29896207 PMCID: PMC5987165 DOI: 10.3389/fpls.2018.00691] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 05/07/2018] [Indexed: 06/08/2023]
Abstract
WD40-repeat (WDR) domain-containing proteins are subunits of multi-protein E3 ligase complexes regulating various cellular and developmental activities in eukaryotes. Chlamydomonas reinhardtii serves as a model organism to study lipid metabolism in microalgae. Under nutrition deficient conditions, C. reinhardtii accumulates lipids for survival. The proteins in C. reinhardtii flagella have diverse functions, such as controlling the motility and cell cycle, and environment sensing. Here, we characterized the function of CrFAP89, a flagella-associated WDR-containing protein, which was identified from C. reinhardtii nitrogen deficiency transcriptome analysis. Quantitative real time-PCR showed that the transcription levels of CrFAP89 were significantly enhanced upon nutrient deprivation, including nitrogen, sulfur, or iron starvation, which is considered an effective condition to promote triacylglycerol (TAG) accumulation in microalgae. Under sulfur starvation, the expression of CrFAP89 was 32.2-fold higher than the control. Furthermore, two lines of RNAi mutants of CrFAP89 were generated by transformation, with gene silencing of 24.9 and 16.4%, respectively. Inhibiting the expression of the CrFAP89 gene drastically increased cell density by 112-125% and resulted in larger cells, that more tolerant to nutrition starvation. However, the content of neutral lipids declined by 12.8-19.6%. The fatty acid content in the transgenic algae decreased by 12.4 and 13.3%, mostly decreasing the content of C16:0, C16:4, C18, and C20:1 fatty acids, while the C16:1 fatty acid in the CrFAP89 RNAi lines increased by 238.5 to 318.5%. Suppressed expression of TAG biosynthesis-related genes, such as CrDGAT1 and CrDGTTs, were detected in CrFAP89 gene silencing cells, with a reduction of 16-78%. Overall our results suggest that down-regulating of the expression of CrFAP89 in C. reinhardtii, resulting in an increase of cell growth and a decrease of fatty acid synthesis with the most significant decrease occurring in C16:0, C16:4, C18, and C20:1 fatty acid. CrFAP89 might be a regulator for lipid accumulation in C. reinhardtii.
Collapse
Affiliation(s)
- Qiulan Luo
- Guangdong Technology Research Center for Marine Algal Bioengineering, Guangdong Key Laboratory of Plant Epigenetic, Shenzhen Key Laboratory of Marine Bioresource & Eco-environmental Sciences, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, China
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Wenwen Song
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, China
| | - Yajun Li
- Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Chaogang Wang
- Guangdong Technology Research Center for Marine Algal Bioengineering, Guangdong Key Laboratory of Plant Epigenetic, Shenzhen Key Laboratory of Marine Bioresource & Eco-environmental Sciences, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, China
| | - Zhangli Hu
- Guangdong Technology Research Center for Marine Algal Bioengineering, Guangdong Key Laboratory of Plant Epigenetic, Shenzhen Key Laboratory of Marine Bioresource & Eco-environmental Sciences, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
- Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, China
| |
Collapse
|
17
|
Hantzis LJ, Kroh GE, Jahn CE, Cantrell M, Peers G, Pilon M, Ravet K. A Program for Iron Economy during Deficiency Targets Specific Fe Proteins. PLANT PHYSIOLOGY 2018; 176:596-610. [PMID: 29150559 DOI: 10.1104/pp1701497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/15/2017] [Indexed: 05/22/2023]
Abstract
Iron (Fe) is an essential element for plants, utilized in nearly every cellular process. Because the adjustment of uptake under Fe limitation cannot satisfy all demands, plants need to acclimate their physiology and biochemistry, especially in their chloroplasts, which have a high demand for Fe. To investigate if a program exists for the utilization of Fe under deficiency, we analyzed how hydroponically grown Arabidopsis (Arabidopsis thaliana) adjusts its physiology and Fe protein composition in vegetative photosynthetic tissue during Fe deficiency. Fe deficiency first affected photosynthetic electron transport with concomitant reductions in carbon assimilation and biomass production when effects on respiration were not yet significant. Photosynthetic electron transport function and protein levels of Fe-dependent enzymes were fully recovered upon Fe resupply, indicating that the Fe depletion stress did not cause irreversible secondary damage. At the protein level, ferredoxin, the cytochrome-b6f complex, and Fe-containing enzymes of the plastid sulfur assimilation pathway were major targets of Fe deficiency, whereas other Fe-dependent functions were relatively less affected. In coordination, SufA and SufB, two proteins of the plastid Fe-sulfur cofactor assembly pathway, were also diminished early by Fe depletion. Iron depletion reduced mRNA levels for the majority of the affected proteins, indicating that loss of enzyme was not just due to lack of Fe cofactors. SufB and ferredoxin were early targets of transcript down-regulation. The data reveal a hierarchy for Fe utilization in photosynthetic tissue and indicate that a program is in place to acclimate to impending Fe deficiency.
Collapse
Affiliation(s)
- Laura J Hantzis
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Gretchen E Kroh
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Courtney E Jahn
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, Colorado 80523-1177
| | - Michael Cantrell
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Graham Peers
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Marinus Pilon
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Karl Ravet
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
- INRA, Institut de Biologie Intégrative des Plantes, 34060 Montpellier, France
| |
Collapse
|
18
|
Hantzis LJ, Kroh GE, Jahn CE, Cantrell M, Peers G, Pilon M, Ravet K. A Program for Iron Economy during Deficiency Targets Specific Fe Proteins. PLANT PHYSIOLOGY 2018; 176:596-610. [PMID: 29150559 PMCID: PMC5761800 DOI: 10.1104/pp.17.01497] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/15/2017] [Indexed: 05/04/2023]
Abstract
Iron (Fe) is an essential element for plants, utilized in nearly every cellular process. Because the adjustment of uptake under Fe limitation cannot satisfy all demands, plants need to acclimate their physiology and biochemistry, especially in their chloroplasts, which have a high demand for Fe. To investigate if a program exists for the utilization of Fe under deficiency, we analyzed how hydroponically grown Arabidopsis (Arabidopsis thaliana) adjusts its physiology and Fe protein composition in vegetative photosynthetic tissue during Fe deficiency. Fe deficiency first affected photosynthetic electron transport with concomitant reductions in carbon assimilation and biomass production when effects on respiration were not yet significant. Photosynthetic electron transport function and protein levels of Fe-dependent enzymes were fully recovered upon Fe resupply, indicating that the Fe depletion stress did not cause irreversible secondary damage. At the protein level, ferredoxin, the cytochrome-b6f complex, and Fe-containing enzymes of the plastid sulfur assimilation pathway were major targets of Fe deficiency, whereas other Fe-dependent functions were relatively less affected. In coordination, SufA and SufB, two proteins of the plastid Fe-sulfur cofactor assembly pathway, were also diminished early by Fe depletion. Iron depletion reduced mRNA levels for the majority of the affected proteins, indicating that loss of enzyme was not just due to lack of Fe cofactors. SufB and ferredoxin were early targets of transcript down-regulation. The data reveal a hierarchy for Fe utilization in photosynthetic tissue and indicate that a program is in place to acclimate to impending Fe deficiency.
Collapse
Affiliation(s)
- Laura J Hantzis
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Gretchen E Kroh
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Courtney E Jahn
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, Colorado 80523-1177
| | - Michael Cantrell
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Graham Peers
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Marinus Pilon
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
| | - Karl Ravet
- Biology Department, Colorado State University, Fort Collins, Colorado 80523-1878
- INRA, Institut de Biologie Intégrative des Plantes, 34060 Montpellier, France
| |
Collapse
|
19
|
Kona R, Hemalatha M, Venu Srivastav K, Venkata Mohan S. Regulatory effect of Fe-EDTA on mixotrophic cultivation of Chlorella sp. towards biomass growth and metabolite production. BIORESOURCE TECHNOLOGY 2017; 244:1227-1234. [PMID: 28687189 DOI: 10.1016/j.biortech.2017.06.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 06/02/2017] [Accepted: 06/05/2017] [Indexed: 05/28/2023]
Abstract
The study examined the effect of varying concentrations of iron in the form of ethylene diamine tetra-acetic acid ferric sodium salt (Fe-EDTA) for cultivation of Chlorella sp. under mixotrophic condition to evaluate biomass growth and metabolites production. The experimental data depicted enhanced biomass production along with lipids, carbohydrates and proteins at an optimal iron concentration (8mg/L). Relatively higher biomass production (5.4g/L; 96h) with simultaneous total chlorophyll (5mg/mL (Chl a/b: 3.7/1.3mg/mL)), carbohydrates (105mg/g) and proteins (593mg/g) was observed with 8 mg/L Fe-EDTA. Total and neutral lipid content of 38% and 15.6% was observed under nutrient deprived conditions. The presence of iron showed distinct influence on the saturated fraction of FAME and increment in oleic acid (omega fatty acids; edible oil). Higher concentrations of Fe-EDTA (10/12mg/L) depicted incremental fraction of oleic acid.
Collapse
Affiliation(s)
- Rajesh Kona
- Bioengineering and Environmental Science Lab, EEFF Department, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - Manupati Hemalatha
- Bioengineering and Environmental Science Lab, EEFF Department, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - K Venu Srivastav
- Bioengineering and Environmental Science Lab, EEFF Department, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - S Venkata Mohan
- Bioengineering and Environmental Science Lab, EEFF Department, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
| |
Collapse
|
20
|
Blaby-Haas CE, Merchant SS. Regulating cellular trace metal economy in algae. CURRENT OPINION IN PLANT BIOLOGY 2017; 39:88-96. [PMID: 28672168 PMCID: PMC5595633 DOI: 10.1016/j.pbi.2017.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 05/05/2023]
Abstract
As indispensable protein cofactors, Fe, Mn, Cu and Zn are at the center of multifaceted acclimation mechanisms that have evolved to ensure extracellular supply meets intracellular demand. Starting with selective transport at the plasma membrane and ending in protein metalation, metal homeostasis in algae involves regulated trafficking of metal ions across membranes, intracellular compartmentalization by proteins and organelles, and metal-sparing/recycling mechanisms to optimize metal-use efficiency. Overlaid on these processes are additional circuits that respond to the metabolic state as well as to the prior metal status of the cell. In this review, we focus on recent progress made toward understanding the pathways by which the single-celled, green alga Chlamydomonas reinhardtii controls its cellular trace metal economy. We also compare these mechanisms to characterized and putative processes in other algal lineages. Photosynthetic microbes continue to provide insight into cellular regulation and handling of Cu, Fe, Zn and Mn as a function of the nutritional supply and cellular demand for metal cofactors. New experimental tools such as RNA-Seq and subcellular metal imaging are bringing us closer to a molecular understanding of acclimation to supply dynamics in algae and beyond.
Collapse
Affiliation(s)
- Crysten E Blaby-Haas
- Biology Department, Brookhaven National Laboratory, 50 Bell Avenue, Building 463, Upton, NY 11973, USA.
| | - Sabeeha S Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, USA; Institute for Genomics and Proteomics, University of California, Los Angeles, 611 Charles E. Young Drive East, Los Angeles, USA
| |
Collapse
|
21
|
Rizwan M, Mujtaba G, Lee K. Effects of iron sources on the growth and lipid/carbohydrate production of marine microalga Dunaliella tertiolecta. BIOTECHNOL BIOPROC E 2017. [DOI: 10.1007/s12257-016-0628-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
22
|
Dammak M, Hadrich B, Miladi R, Barkallah M, Hentati F, Hachicha R, Laroche C, Michaud P, Fendri I, Abdelkafi S. Effects of nutritional conditions on growth and biochemical composition of Tetraselmis sp. Lipids Health Dis 2017; 16:41. [PMID: 28219380 PMCID: PMC5319095 DOI: 10.1186/s12944-016-0378-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 11/24/2016] [Indexed: 11/18/2022] Open
Abstract
Background This study aimed to maximize biomass concentration, biomass productivity and biochemical composition of the marine microalga Tetraselmis sp. Methods In the current study, Box-Behnken Design was used to model the effect of NaNO3, NaH2PO4, metals and vitamins in the F/2 medium on the growth, total chlorophylls, carotenoids and starch contents. The total chlorophylls content was quantified by spectrophotometry. The FT-IR spectroscopy was used to estimate the biochemical compositions of Tetraselmis sp. grown under both optimized medium culture for starch production and standard culture medium. Results Finalized NaNO3 (1.76 mM), NaH2PO4 (0.018 mM), metals (1500 μL.L−1) and vitamins (312.5 μL.L−1) concentrations, generated an increase in biomass concentration up to 5.72 g.L−1 which contributed to an increase about 2.4-fold than that of the standard conditions of biomass productivity (408.57 mg.L−1.day−1). The maximum value of carotenoids content (0.3 mg.g DW−1) was achieved at the highest level of all factors. The total chlorophylls content reached also its maximum (5.18 mg.g DW−1) at high nitrate (1.76 mM), phosphate (0.054 mM), metals and vitamins concentrations, while the maximum starch content (42% DW) was achieved with low nitrate and phosphate concentrations (0.58 mM and 0.027 mM) and with metals and vitamins limitations. Thus, the nitrogen, phosphorus, metals and vitamins limitations led to divert the metabolism for the starch biosynthesis. Conclusions The high biomass concentration productivity and starch production make Tetraselmis sp. strain a good candidate for biotechnological applications.
Collapse
Affiliation(s)
- Mouna Dammak
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Bilel Hadrich
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Ramzi Miladi
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Mohamed Barkallah
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Faiez Hentati
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Ridha Hachicha
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Céline Laroche
- Université Clermont Auvergne, Université Blaise Pascal, Institut Pascal, BP 10448, F-63000, Clermont-Ferrand, France.,CNRS, UMR 6602, IP, F-63178, Aubière, France
| | - Philippe Michaud
- Université Clermont Auvergne, Université Blaise Pascal, Institut Pascal, BP 10448, F-63000, Clermont-Ferrand, France.,CNRS, UMR 6602, IP, F-63178, Aubière, France
| | - Imen Fendri
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Slim Abdelkafi
- Unité de Biotechnologie des Algues, Biological Engineering Department, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia.
| |
Collapse
|
23
|
Devadasu ER, Madireddi SK, Nama S, Subramanyam R. Iron deficiency cause changes in photochemistry, thylakoid organization, and accumulation of photosystem II proteins in Chlamydomonas reinhardtii. PHOTOSYNTHESIS RESEARCH 2016; 130:469-478. [PMID: 27325385 DOI: 10.1007/s11120-016-0284-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/13/2016] [Indexed: 05/11/2023]
Abstract
A trace element, iron (Fe) plays a pivotal role in photosynthesis process which in turn mediates the plant growth and productivity. Here, we have focused majorly on the photochemistry of photosystem (PS) II, abundance of proteins, and organization of supercomplexes of thylakoids from Fe-depleted cells in Chlamydomonas reinhardtii. Confocal pictures show that the cell's size has been reduced and formed rosette-shaped palmelloids; however, there is no cell death. Further, the PSII photochemistry was reduced remarkably. Further, the photosynthetic efficiency analyzer data revealed that both donor and acceptor side of PSII were equally damaged. Additionally, the room-temperature emission spectra showed the fluorescence emission maxima increased due to impaired energy transfer from PSII to PSI. Furthermore, the protein data reveal that most of the proteins of reaction center and light-harvesting antenna were reduced in Fe-depleted cells. Additionally, the supercomplexes of PSI and PSII were destabilized from thylakoids under Fe-deficient condition showing that Fe is an important element in photosynthesis mechanism.
Collapse
Affiliation(s)
- Elsin Raju Devadasu
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Sai Kiran Madireddi
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Srilatha Nama
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Rajagopal Subramanyam
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India.
| |
Collapse
|
24
|
Treves H, Raanan H, Kedem I, Murik O, Keren N, Zer H, Berkowicz SM, Giordano M, Norici A, Shotland Y, Ohad I, Kaplan A. The mechanisms whereby the green alga Chlorella ohadii, isolated from desert soil crust, exhibits unparalleled photodamage resistance. THE NEW PHYTOLOGIST 2016; 210:1229-43. [PMID: 26853530 DOI: 10.1111/nph.13870] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/16/2015] [Indexed: 05/24/2023]
Abstract
Excess illumination damages the photosynthetic apparatus with severe implications with regard to plant productivity. Unlike model organisms, the growth of Chlorella ohadii, isolated from desert soil crust, remains unchanged and photosynthetic O2 evolution increases, even when exposed to irradiation twice that of maximal sunlight. Spectroscopic, biochemical and molecular approaches were applied to uncover the mechanisms involved. D1 protein in photosystem II (PSII) is barely degraded, even when exposed to antibiotics that prevent its replenishment. Measurements of various PSII parameters indicate that this complex functions differently from that in model organisms and suggest that C. ohadii activates a nonradiative electron recombination route which minimizes singlet oxygen formation and the resulting photoinhibition. The light-harvesting antenna is very small and carotene composition is hardly affected by excess illumination. Instead of succumbing to photodamage, C. ohadii activates additional means to dissipate excess light energy. It undergoes major structural, compositional and physiological changes, leading to a large rise in photosynthetic rate, lipids and carbohydrate content and inorganic carbon cycling. The ability of C. ohadii to avoid photodamage relies on a modified function of PSII and the dissipation of excess reductants downstream of the photosynthetic reaction centers. The biotechnological potential as a gene source for crop plant improvement is self-evident.
Collapse
Affiliation(s)
- Haim Treves
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Hagai Raanan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Isaac Kedem
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Omer Murik
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Nir Keren
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Hagit Zer
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Simon M Berkowicz
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Mario Giordano
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, 60131, Italy
| | - Alessandra Norici
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, 60131, Italy
| | - Yoram Shotland
- Department of Chemical Engineering, Shamoon College of Engineering, Beer Sheva, 84100, Israel
| | - Itzhak Ohad
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Aaron Kaplan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| |
Collapse
|
25
|
Douchi D, Qu Y, Longoni P, Legendre-Lefebvre L, Johnson X, Schmitz-Linneweber C, Goldschmidt-Clermont M. A Nucleus-Encoded Chloroplast Phosphoprotein Governs Expression of the Photosystem I Subunit PsaC in Chlamydomonas reinhardtii. THE PLANT CELL 2016; 28:1182-99. [PMID: 27113776 PMCID: PMC4904667 DOI: 10.1105/tpc.15.00725] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 04/25/2016] [Indexed: 05/05/2023]
Abstract
The nucleo-cytoplasmic compartment exerts anterograde control on chloroplast gene expression through numerous proteins that intervene at posttranscriptional steps. Here, we show that the maturation of psaC mutant (mac1) of Chlamydomonas reinhardtii is defective in photosystem I and fails to accumulate psaC mRNA. The MAC1 locus encodes a member of the Half-A-Tetratricopeptide (HAT) family of super-helical repeat proteins, some of which are involved in RNA transactions. The Mac1 protein localizes to the chloroplast in the soluble fraction. MAC1 acts through the 5' untranslated region of psaC transcripts and is required for their stability. Small RNAs that map to the 5'end of psaC RNA in the wild type but not in the mac1 mutant are inferred to represent footprints of MAC1-dependent protein binding, and Mac1 expressed in bacteria binds RNA in vitro. A coordinate response to iron deficiency, which leads to dismantling of the photosynthetic electron transfer chain and in particular of photosystem I, also causes a decrease of Mac1. Overexpression of Mac1 leads to a parallel increase in psaC mRNA but not in PsaC protein, suggesting that Mac1 may be limiting for psaC mRNA accumulation but that other processes regulate protein accumulation. Furthermore, Mac 1 is differentially phosphorylated in response to iron availability and to conditions that alter the redox balance of the electron transfer chain.
Collapse
Affiliation(s)
- Damien Douchi
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland
| | - Yujiao Qu
- Institute of Biology, Molecular Genetics, Humboldt University of Berlin, D-10115 Berlin, Germany
| | - Paolo Longoni
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland
| | - Linnka Legendre-Lefebvre
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland
| | - Xenie Johnson
- Unité Mixte de Recherche 7141, CNRS/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France
| | | | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland
| |
Collapse
|
26
|
Saroussi SI, Wittkopp TM, Grossman AR. The Type II NADPH Dehydrogenase Facilitates Cyclic Electron Flow, Energy-Dependent Quenching, and Chlororespiratory Metabolism during Acclimation of Chlamydomonas reinhardtii to Nitrogen Deprivation. PLANT PHYSIOLOGY 2016; 170:1975-88. [PMID: 26858365 PMCID: PMC4825143 DOI: 10.1104/pp.15.02014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 02/05/2016] [Indexed: 05/18/2023]
Abstract
When photosynthetic organisms are deprived of nitrogen (N), the capacity to grow and assimilate carbon becomes limited, causing a decrease in the productive use of absorbed light energy and likely a rise in the cellular reduction state. Although there is a scarcity of N in many terrestrial and aquatic environments, a mechanistic understanding of how photosynthesis adjusts to low-N conditions and the enzymes/activities integral to these adjustments have not been described. In this work, we use biochemical and biophysical analyses of photoautotrophically grown wild-type and mutant strains of Chlamydomonas reinhardtii to determine the integration of electron transport pathways critical for maintaining active photosynthetic complexes even after exposure of cells to N deprivation for 3 d. Key to acclimation is the type II NADPH dehydrogenase, NDA2, which drives cyclic electron flow (CEF), chlororespiration, and the generation of an H(+) gradient across the thylakoid membranes. N deprivation elicited a doubling of the rate of NDA2-dependent CEF, with little contribution from PGR5/PGRL1-dependent CEF The H(+) gradient generated by CEF is essential to sustain nonphotochemical quenching, while an increase in the level of reduced plastoquinone would promote a state transition; both are necessary to down-regulate photosystem II activity. Moreover, stimulation of NDA2-dependent chlororespiration affords additional relief from the elevated reduction state associated with N deprivation through plastid terminal oxidase-dependent water synthesis. Overall, rerouting electrons through the NDA2 catalytic hub in response to photoautotrophic N deprivation sustains cell viability while promoting the dissipation of excess excitation energy through quenching and chlororespiratory processes.
Collapse
Affiliation(s)
- Shai I Saroussi
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (S.I.S., T.M.W., A.R.G.); andDepartment of Biology, Stanford University, Stanford, California 94305-5020 (T.M.W.)
| | - Tyler M Wittkopp
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (S.I.S., T.M.W., A.R.G.); andDepartment of Biology, Stanford University, Stanford, California 94305-5020 (T.M.W.)
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305 (S.I.S., T.M.W., A.R.G.); andDepartment of Biology, Stanford University, Stanford, California 94305-5020 (T.M.W.)
| |
Collapse
|
27
|
Microfluidic high-throughput selection of microalgal strains with superior photosynthetic productivity using competitive phototaxis. Sci Rep 2016; 6:21155. [PMID: 26852806 PMCID: PMC4745075 DOI: 10.1038/srep21155] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 11/30/2015] [Indexed: 12/02/2022] Open
Abstract
Microalgae possess great potential as a source of sustainable energy, but the intrinsic inefficiency of photosynthesis is a major challenge to realize this potential. Photosynthetic organisms evolved phototaxis to find optimal light condition for photosynthesis. Here we report a microfluidic screening using competitive phototaxis of the model alga, Chlamydomonas reinhardtii, for rapid isolation of strains with improved photosynthetic efficiencies. We demonstrated strong relationship between phototaxis and photosynthetic efficiency by quantitative analysis of phototactic response at the single-cell level using a microfluidic system. Based on this positive relationship, we enriched the strains with improved photosynthetic efficiency by isolating cells showing fast phototactic responses from a mixture of 10,000 mutants, thereby greatly improving selection efficiency over 8 fold. Among 147 strains isolated after screening, 94.6% showed improved photoautotrophic growth over the parental strain. Two mutants showed much improved performances with up to 1.9- and 8.1-fold increases in photoautotrophic cell growth and lipid production, respectively, a substantial improvement over previous approaches. We identified candidate genes that might be responsible for fast phototactic response and improved photosynthesis, which can be useful target for further strain engineering. Our approach provides a powerful screening tool for rapid improvement of microalgal strains to enhance photosynthetic productivity.
Collapse
|
28
|
Lefebvre-Legendre L, Choquet Y, Kuras R, Loubéry S, Douchi D, Goldschmidt-Clermont M. A nucleus-encoded chloroplast protein regulated by iron availability governs expression of the photosystem I subunit PsaA in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2015; 167:1527-40. [PMID: 25673777 PMCID: PMC4378161 DOI: 10.1104/pp.114.253906] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The biogenesis of the photosynthetic electron transfer chain in the thylakoid membranes requires the concerted expression of genes in the chloroplast and the nucleus. Chloroplast gene expression is subjected to anterograde control by a battery of nucleus-encoded proteins that are imported in the chloroplast, where they mostly intervene at posttranscriptional steps. Using a new genetic screen, we identify a nuclear mutant that is required for expression of the PsaA subunit of photosystem I (PSI) in the chloroplast of Chlamydomonas reinhardtii. This mutant is affected in the stability and translation of psaA messenger RNA. The corresponding gene, TRANSLATION OF psaA1 (TAA1), encodes a large protein with two domains that are thought to mediate RNA binding: an array of octatricopeptide repeats (OPR) and an RNA-binding domain abundant in apicomplexans (RAP) domain. We show that as expected for its function, TAA1 is localized in the chloroplast. It was previously shown that when mixotrophic cultures of C. reinhardtii (which use both photosynthesis and mitochondrial respiration for growth) are shifted to conditions of iron limitation, there is a strong decrease in the accumulation of PSI and that this is rapidly reversed when iron is resupplied. Under these conditions, TAA1 protein is also down-regulated through a posttranscriptional mechanism and rapidly reaccumulates when iron is restored. These observations reveal a concerted regulation of PSI and of TAA1 in response to iron availability.
Collapse
Affiliation(s)
- Linnka Lefebvre-Legendre
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Yves Choquet
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Richard Kuras
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Sylvain Loubéry
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Damien Douchi
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology and Department of Molecular Biology, University of Geneva, 1211 Geneva 4, Switzerland (L.L.-L., S.L., D.D., M.G.-C.); andUnité Mixte de Recherche 7141, Centre National de la Recherche Scientifique/Université Pierre et Marie Curie, Institut de Biologie Physico-Chimique, 75005 Paris, France (Y.C., R.K.)
| |
Collapse
|
29
|
Wan M, Jin X, Xia J, Rosenberg JN, Yu G, Nie Z, Oyler GA, Betenbaugh MJ. The effect of iron on growth, lipid accumulation, and gene expression profile of the freshwater microalga Chlorella sorokiniana. Appl Microbiol Biotechnol 2014; 98:9473-81. [PMID: 25248441 DOI: 10.1007/s00253-014-6088-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 09/02/2014] [Accepted: 09/09/2014] [Indexed: 10/24/2022]
Abstract
The effects of iron on the growth, lipid accumulation, and gene expression profiles of the limnetic Chlorella sorokiniana CCTCC M209220 under photoautotrophy were investigated. The addition of iron up to 10(-5) mol l(-l) increased final cell densities by nearly 2-fold at 2.3 × 10(7) cells/ml, growth rate by 2-fold, and the length of the exponential phase by 5 days as compared to unsupplemented controls while 10(-3) mol l(-1) iron was toxic. The lipid content increased from 12 % for unsupplemented cultures to 33 % at 10(-4) mol l(-1) iron while the highest overall lipid yield reached 179 mg l(-1). A genefishing and qPCR comparison between the C. sorokiniana at low and high iron levels indicated increases in the expression of several genes, including carbonic anhydrase involved in microalgal cell growth, as well as acc1 and choline transporter related to lipid synthesis. This study provides insights into changes in gene expression and metabolism that accompany iron supplementation to Chlorella as well as potential metabolic engineering targets for improving growth and lipid synthesis in microalgae.
Collapse
Affiliation(s)
- Minxi Wan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Lefebvre-Legendre L, Merendino L, Rivier C, Goldschmidt-Clermont M. On the Complexity of Chloroplast RNA Metabolism: psaA Trans-splicing Can be Bypassed in Chlamydomonas. Mol Biol Evol 2014; 31:2697-707. [DOI: 10.1093/molbev/msu215] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
31
|
Schmollinger S, Mühlhaus T, Boyle NR, Blaby IK, Casero D, Mettler T, Moseley JL, Kropat J, Sommer F, Strenkert D, Hemme D, Pellegrini M, Grossman AR, Stitt M, Schroda M, Merchant SS. Nitrogen-Sparing Mechanisms in Chlamydomonas Affect the Transcriptome, the Proteome, and Photosynthetic Metabolism. THE PLANT CELL 2014; 26:1410-1435. [PMID: 24748044 PMCID: PMC4036562 DOI: 10.1105/tpc.113.122523] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/19/2014] [Accepted: 03/29/2014] [Indexed: 05/17/2023]
Abstract
Nitrogen (N) is a key nutrient that limits global primary productivity; hence, N-use efficiency is of compelling interest in agriculture and aquaculture. We used Chlamydomonas reinhardtii as a reference organism for a multicomponent analysis of the N starvation response. In the presence of acetate, respiratory metabolism is prioritized over photosynthesis; consequently, the N-sparing response targets proteins, pigments, and RNAs involved in photosynthesis and chloroplast function over those involved in respiration. Transcripts and proteins of the Calvin-Benson cycle are reduced in N-deficient cells, resulting in the accumulation of cycle metabolic intermediates. Both cytosolic and chloroplast ribosomes are reduced, but via different mechanisms, reflected by rapid changes in abundance of RNAs encoding chloroplast ribosomal proteins but not cytosolic ones. RNAs encoding transporters and enzymes for metabolizing alternative N sources increase in abundance, as is appropriate for the soil environmental niche of C. reinhardtii. Comparison of the N-replete versus N-deplete proteome indicated that abundant proteins with a high N content are reduced in N-starved cells, while the proteins that are increased have lower than average N contents. This sparing mechanism contributes to a lower cellular N/C ratio and suggests an approach for engineering increased N-use efficiency.
Collapse
Affiliation(s)
- Stefan Schmollinger
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Timo Mühlhaus
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Nanette R Boyle
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Ian K Blaby
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - David Casero
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
| | - Tabea Mettler
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Jeffrey L Moseley
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Janette Kropat
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Frederik Sommer
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Daniela Strenkert
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Dorothea Hemme
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095 Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Michael Schroda
- Molecular Biotechnology and Systems Biology, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany Max Planck Institute of Molecular Plant Physiology, D-14476 Potsdam-Golm, Germany
| | - Sabeeha S Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095 Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
| |
Collapse
|
32
|
Sun X, Cao Y, Xu H, Liu Y, Sun J, Qiao D, Cao Y. Effect of nitrogen-starvation, light intensity and iron on triacylglyceride/carbohydrate production and fatty acid profile of Neochloris oleoabundans HK-129 by a two-stage process. BIORESOURCE TECHNOLOGY 2014; 155:204-12. [PMID: 24457305 DOI: 10.1016/j.biortech.2013.12.109] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/22/2013] [Accepted: 12/25/2013] [Indexed: 05/11/2023]
Abstract
Triacylglyceride (TAG) and carbohydrate are potential feedstock for biofuels production. In this study, a two-stage process was applied for enhancing TAG/carbohydrate production in the selected microalgae - Neochloris oleoabundans HK-129. In stage I, effects of nitrogen, light intensity and iron on cell growth were investigated, and the highest biomass productivity of 292.83±5.83mg/L/d was achieved. In stage II, different nitrogen-starvation periods, light intensities and iron concentrations were employed to trigger accumulation of TAG and carbohydrate. The culture under 2-day N-starvation, 200μmol/m(2)/s light intensity and 0.037mM Fe(3+) concentration produced the maximum TAG and carbohydrate productivity of 51.58mg/L/d and 90.70mg/L/d, respectively. Nitrogen starvation period and light intensity had marked effects on TAG/carbohydrate accumulation and fatty acids profile, compared to iron concentration. The microalgal lipid was mainly composed of C16/C18 fatty acids (90.02%), saturated fatty acids (29.82%), and monounsaturated fatty acids (32.67%), which is suitable for biodiesel synthesis.
Collapse
Affiliation(s)
- Xian Sun
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Yu Cao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Hui Xu
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Yan Liu
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Jianrui Sun
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Dairong Qiao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China
| | - Yi Cao
- Microbiology and Metabolic Engineering Key Laboratory of Sichuan Province, College of Life Science, Sichuan University, Chengdu 610064, Sichuan, China.
| |
Collapse
|
33
|
Wei L, Derrien B, Gautier A, Houille-Vernes L, Boulouis A, Saint-Marcoux D, Malnoë A, Rappaport F, de Vitry C, Vallon O, Choquet Y, Wollman FA. Nitric oxide-triggered remodeling of chloroplast bioenergetics and thylakoid proteins upon nitrogen starvation in Chlamydomonas reinhardtii. THE PLANT CELL 2014; 26:353-72. [PMID: 24474630 PMCID: PMC3963581 DOI: 10.1105/tpc.113.120121] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 12/04/2013] [Accepted: 01/10/2014] [Indexed: 05/18/2023]
Abstract
Starving microalgae for nitrogen sources is commonly used as a biotechnological tool to boost storage of reduced carbon into starch granules or lipid droplets, but the accompanying changes in bioenergetics have been little studied so far. Here, we report that the selective depletion of Rubisco and cytochrome b6f complex that occurs when Chlamydomonas reinhardtii is starved for nitrogen in the presence of acetate and under normoxic conditions is accompanied by a marked increase in chlororespiratory enzymes, which converts the photosynthetic thylakoid membrane into an intracellular matrix for oxidative catabolism of reductants. Cytochrome b6f subunits and most proteins specifically involved in their biogenesis are selectively degraded, mainly by the FtsH and Clp chloroplast proteases. This regulated degradation pathway does not require light, active photosynthesis, or state transitions but is prevented when respiration is impaired or under phototrophic conditions. We provide genetic and pharmacological evidence that NO production from intracellular nitrite governs this degradation pathway: Addition of a NO scavenger and of two distinct NO producers decrease and increase, respectively, the rate of cytochrome b6f degradation; NO-sensitive fluorescence probes, visualized by confocal microscopy, demonstrate that nitrogen-starved cells produce NO only when the cytochrome b6f degradation pathway is activated.
Collapse
Affiliation(s)
- Lili Wei
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Benoit Derrien
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Arnaud Gautier
- École Normale Supérieure,
Département de Chimie, Unité Mixte de Recherche, CNRS–Ecole
Normale Supérieure–Université Pierre et Marie Curie 8640,
75231 Paris Cedex 05, France
| | - Laura Houille-Vernes
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Alix Boulouis
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Denis Saint-Marcoux
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Alizée Malnoë
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Fabrice Rappaport
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Catherine de Vitry
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Olivier Vallon
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Yves Choquet
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| | - Francis-André Wollman
- Unité Mixte de Recherche 7141,
CNRS/Université Pierre et Marie Curie, Institut de Biologie
Physico-Chimique, F-75005 Paris, France
| |
Collapse
|
34
|
Höhner R, Barth J, Magneschi L, Jaeger D, Niehues A, Bald T, Grossman A, Fufezan C, Hippler M. The metabolic status drives acclimation of iron deficiency responses in Chlamydomonas reinhardtii as revealed by proteomics based hierarchical clustering and reverse genetics. Mol Cell Proteomics 2013; 12:2774-90. [PMID: 23820728 PMCID: PMC3790290 DOI: 10.1074/mcp.m113.029991] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/04/2013] [Indexed: 11/06/2022] Open
Abstract
Iron is a crucial cofactor in numerous redox-active proteins operating in bioenergetic pathways including respiration and photosynthesis. Cellular iron management is essential to sustain sufficient energy production and minimize oxidative stress. To produce energy for cell growth, the green alga Chlamydomonas reinhardtii possesses the metabolic flexibility to use light and/or carbon sources such as acetate. To investigate the interplay between the iron-deficiency response and growth requirements under distinct trophic conditions, we took a quantitative proteomics approach coupled to innovative hierarchical clustering using different "distance-linkage combinations" and random noise injection. Protein co-expression analyses of the combined data sets revealed insights into cellular responses governing acclimation to iron deprivation and regulation associated with photosynthesis dependent growth. Photoautotrophic growth requirements as well as the iron deficiency induced specific metabolic enzymes and stress related proteins, and yet differences in the set of induced enzymes, proteases, and redox-related polypeptides were evident, implying the establishment of distinct response networks under the different conditions. Moreover, our data clearly support the notion that the iron deficiency response includes a hierarchy for iron allocation within organelles in C. reinhardtii. Importantly, deletion of a bifunctional alcohol and acetaldehyde dehydrogenase (ADH1), which is induced under low iron based on the proteomic data, attenuates the remodeling of the photosynthetic machinery in response to iron deficiency, and at the same time stimulates expression of stress-related proteins such as NDA2, LHCSR3, and PGRL1. This finding provides evidence that the coordinated regulation of bioenergetics pathways and iron deficiency response is sensitive to the cellular and chloroplast metabolic and/or redox status, consistent with systems approach data.
Collapse
Affiliation(s)
- Ricarda Höhner
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Johannes Barth
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Leonardo Magneschi
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Daniel Jaeger
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Anna Niehues
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Till Bald
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Arthur Grossman
- §Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Christian Fufezan
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| | - Michael Hippler
- From the ‡Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, Münster 48143, Germany
| |
Collapse
|
35
|
Glaesener AG, Merchant SS, Blaby-Haas CE. Iron economy in Chlamydomonas reinhardtii. FRONTIERS IN PLANT SCIENCE 2013; 4:337. [PMID: 24032036 PMCID: PMC3759009 DOI: 10.3389/fpls.2013.00337] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 08/09/2013] [Indexed: 05/05/2023]
Abstract
While research on iron nutrition in plants has largely focused on iron-uptake pathways, photosynthetic microbes such as the unicellular green alga Chlamydomonas reinhardtii provide excellent experimental systems for understanding iron metabolism at the subcellular level. Several paradigms in iron homeostasis have been established in this alga, including photosystem remodeling in the chloroplast and preferential retention of some pathways and key iron-dependent proteins in response to suboptimal iron supply. This review presents our current understanding of iron homeostasis in Chlamydomonas, with specific attention on characterized responses to changes in iron supply, like iron-deficiency. An overview of frequently used methods for the investigation of iron-responsive gene expression, physiology and metabolism is also provided, including preparation of media, the effect of cell size, cell density and strain choice on quantitative measurements and methods for the determination of metal content and assessing the effect of iron supply on photosynthetic performance.
Collapse
Affiliation(s)
- Anne G. Glaesener
- Department of Chemistry and Biochemistry, University of California, Los AngelesLos Angeles, CA, USA
| | - Sabeeha S. Merchant
- Department of Chemistry and Biochemistry, University of California, Los AngelesLos Angeles, CA, USA
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of CaliforniaLos Angeles, CA, USA
| | - Crysten E. Blaby-Haas
- Department of Chemistry and Biochemistry, University of California, Los AngelesLos Angeles, CA, USA
- *Correspondence: Crysten E. Blaby-Haas, Department of Chemistry and Biochemistry, University of California, Box 951569, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569, USA e-mail:
| |
Collapse
|
36
|
Urzica EI, Vieler A, Hong-Hermesdorf A, Page MD, Casero D, Gallaher SD, Kropat J, Pellegrini M, Benning C, Merchant SS. Remodeling of membrane lipids in iron-starved Chlamydomonas. J Biol Chem 2013; 288:30246-30258. [PMID: 23983122 DOI: 10.1074/jbc.m113.490425] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Chlamydomonas reinhardtii cells exposed to abiotic stresses (e.g. nitrogen, zinc, or phosphorus deficiency) accumulate triacylglycerols (TAG), which are stored in lipid droplets. Here, we report that iron starvation leads to formation of lipid droplets and accumulation of TAGs. This occurs between 12 and 24 h after the switch to iron-starvation medium. C. reinhardtii cells deprived of iron have more saturated fatty acid (FA), possibly due to the loss of function of FA desaturases, which are iron-requiring enzymes with diiron centers. The abundance of a plastid acyl-ACP desaturase (FAB2) is decreased to the same degree as ferredoxin. Ferredoxin is a substrate of the desaturases and has been previously shown to be a major target of the iron deficiency response. The increase in saturated FA (C16:0 and C18:0) is concomitant with the decrease in unsaturated FA (C16:4, C18:3, or C18:4). This change was gradual for diacylglyceryl-N,N,N-trimethylhomoserine (DGTS) and digalactosyldiacylglycerol (DGDG), whereas the monogalactosyldiacylglycerol (MGDG) FA profile remained stable during the first 12 h, whereas MGDG levels were decreasing over the same period of time. These changes were detectable after only 2 h of iron starvation. On the other hand, DGTS and DGDG contents gradually decreased until a minimum was reached after 24-48 h. RNA-Seq analysis of iron-starved C. reinhardtii cells revealed notable changes in many transcripts coding for enzymes involved in FA metabolism. The mRNA abundances of genes coding for components involved in TAG accumulation (diacylglycerol acyltransferases or major lipid droplet protein) were increased. A more dramatic increase at the transcript level has been observed for many lipases, suggesting that major remodeling of lipid membranes occurs during iron starvation in C. reinhardtii.
Collapse
Affiliation(s)
| | - Astrid Vieler
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | | | | | - David Casero
- the Institute of Genomics and Proteomics, and; the Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, California 90095 and
| | | | | | - Matteo Pellegrini
- the Institute of Genomics and Proteomics, and; the Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, California 90095 and
| | - Christoph Benning
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Sabeeha S Merchant
- From the Department of Chemistry and Biochemistry,; the Institute of Genomics and Proteomics, and; the Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, California 90095 and.
| |
Collapse
|
37
|
Blaby-Haas CE, Merchant SS. Iron sparing and recycling in a compartmentalized cell. Curr Opin Microbiol 2013; 16:677-85. [PMID: 23962818 DOI: 10.1016/j.mib.2013.07.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Revised: 07/18/2013] [Accepted: 07/29/2013] [Indexed: 12/31/2022]
Abstract
This review focuses on economizing, prioritizing and recycling iron in Chlamydomonas, a reference organism for discovering mechanisms of acclimation to poor iron nutrition in the plant lineage. The metabolic flexibility of Chlamydomonas offers a unique opportunity to distinguish the impact of iron nutrition on photosynthetic versus respiratory metabolism, and the contribution of subcellular compartments to iron storage and mobilization. Mechanisms of iron sparing include down regulation of protein abundance by transcript reduction or protein degradation. Two well-studied examples of hierarchical iron allocation are the maintenance of FeSOD in the plastid and heterotrophic metabolism in acetate-grown cells at the expense of photosynthetic metabolism. The latter implicates the existence of a pathway for inter-compartment iron recycling when access to iron becomes limiting.
Collapse
Affiliation(s)
- Crysten E Blaby-Haas
- University of California, Los Angeles, Box 951569, Los Angeles, CA 90095-1569, USA.
| | | |
Collapse
|
38
|
Vigani G, Zocchi G, Bashir K, Philippar K, Briat JF. Signals from chloroplasts and mitochondria for iron homeostasis regulation. TRENDS IN PLANT SCIENCE 2013; 18:305-11. [PMID: 23462548 DOI: 10.1016/j.tplants.2013.01.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Revised: 01/19/2013] [Accepted: 01/23/2013] [Indexed: 05/04/2023]
Abstract
Iron (Fe) is an essential element for human nutrition. Given that plants represent a major dietary source of Fe worldwide, it is crucial to understand plant Fe homeostasis fully. A major breakthrough in the understanding of Fe sensing and signaling was the identification of several transcription factor cascades regulating Fe homeostasis. However, the mechanisms of activation of these cascades still remain to be elucidated. In this opinion, we focus on the possible roles of mitochondria and chloroplasts as cellular Fe sensing and signaling sites, offering a new perspective on the integrated regulation of Fe homeostasis and its interplay with cellular metabolism.
Collapse
Affiliation(s)
- Gianpiero Vigani
- Dipartimento di Scienze Agrarie e Ambientali-Produzione, Territorio e Agroenergia, Università degli Studi di Milano, Milan, Italy.
| | | | | | | | | |
Collapse
|
39
|
Hsieh SI, Castruita M, Malasarn D, Urzica E, Erde J, Page MD, Yamasaki H, Casero D, Pellegrini M, Merchant SS, Loo JA. The proteome of copper, iron, zinc, and manganese micronutrient deficiency in Chlamydomonas reinhardtii. Mol Cell Proteomics 2012; 12:65-86. [PMID: 23065468 DOI: 10.1074/mcp.m112.021840] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Trace metals such as copper, iron, zinc, and manganese play important roles in several biochemical processes, including respiration and photosynthesis. Using a label-free, quantitative proteomics strategy (MS(E)), we examined the effect of deficiencies in these micronutrients on the soluble proteome of Chlamydomonas reinhardtii. We quantified >10(3) proteins with abundances within a dynamic range of 3 to 4 orders of magnitude and demonstrated statistically significant changes in ~200 proteins in each metal-deficient growth condition relative to nutrient-replete media. Through analysis of Pearson's coefficient, we also examined the correlation between protein abundance and transcript abundance (as determined via RNA-Seq analysis) and found moderate correlations under all nutritional states. Interestingly, in a subset of transcripts known to significantly change in abundance in metal-replete and metal-deficient conditions, the correlation to protein abundance is much stronger. Examples of new discoveries highlighted in this work include the accumulation of O(2) labile, anaerobiosis-related enzymes (Hyd1, Pfr1, and Hcp2) in copper-deficient cells; co-variation of Cgl78/Ycf54 and coprogen oxidase; the loss of various stromal and lumenal photosynthesis-related proteins, including plastocyanin, in iron-limited cells; a large accumulation (from undetectable amounts to over 1,000 zmol/cell) of two COG0523 domain-containing proteins in zinc-deficient cells; and the preservation of photosynthesis proteins in manganese-deficient cells despite known losses in photosynthetic function in this condition.
Collapse
Affiliation(s)
- Scott I Hsieh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Urzica EI, Casero D, Yamasaki H, Hsieh SI, Adler LN, Karpowicz SJ, Blaby-Haas CE, Clarke SG, Loo JA, Pellegrini M, Merchant SS. Systems and trans-system level analysis identifies conserved iron deficiency responses in the plant lineage. THE PLANT CELL 2012; 24:3921-48. [PMID: 23043051 PMCID: PMC3517228 DOI: 10.1105/tpc.112.102491] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/31/2012] [Accepted: 09/12/2012] [Indexed: 05/03/2023]
Abstract
We surveyed the iron nutrition-responsive transcriptome of Chlamydomonas reinhardtii using RNA-Seq methodology. Presumed primary targets were identified in comparisons between visually asymptomatic iron-deficient versus iron-replete cells. This includes the known components of high-affinity iron uptake as well as candidates for distributive iron transport in C. reinhardtii. Comparison of growth-inhibited iron-limited versus iron-replete cells revealed changes in the expression of genes in chloroplastic oxidative stress response pathways, among hundreds of other genes. The output from the transcriptome was validated at multiple levels: by quantitative RT-PCR for assessing the data analysis pipeline, by quantitative proteomics for assessing the impact of changes in RNA abundance on the proteome, and by cross-species comparison for identifying conserved or universal response pathways. In addition, we assessed the functional importance of three target genes, Vitamin C 2 (VTC2), monodehydroascorbate reductase 1 (MDAR1), and conserved in the green lineage and diatoms 27 (CGLD27), by biochemistry or reverse genetics. VTC2 and MDAR1, which are key enzymes in de novo ascorbate synthesis and ascorbate recycling, respectively, are likely responsible for the 10-fold increase in ascorbate content of iron-limited cells. CGLD27/At5g67370 is a highly conserved, presumed chloroplast-localized pioneer protein and is important for growth of Arabidopsis thaliana in low iron.
Collapse
Affiliation(s)
- Eugen I. Urzica
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - David Casero
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
| | - Hiroaki Yamasaki
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
| | - Scott I. Hsieh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Lital N. Adler
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Steven J. Karpowicz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Crysten E. Blaby-Haas
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Steven G. Clarke
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Joseph A. Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
- Department of Biological Chemistry, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
| | - Sabeeha S. Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, David Geffen School of Medicine at the University of California, Los Angeles, California 90095
| |
Collapse
|
41
|
Blaby-Haas CE, Merchant SS. The ins and outs of algal metal transport. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1823:1531-52. [PMID: 22569643 PMCID: PMC3408858 DOI: 10.1016/j.bbamcr.2012.04.010] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 04/20/2012] [Accepted: 04/23/2012] [Indexed: 10/28/2022]
Abstract
Metal transporters are a central component in the interaction of algae with their environment. They represent the first line of defense to cellular perturbations in metal concentration, and by analyzing algal metal transporter repertoires, we gain insight into a fundamental aspect of algal biology. The ability of individual algae to thrive in environments with unique geochemistry, compared to non-algal species commonly used as reference organisms for metal homeostasis, provides an opportunity to broaden our understanding of biological metal requirements, preferences and trafficking. Chlamydomonas reinhardtii is the best developed reference organism for the study of algal biology, especially with respect to metal metabolism; however, the diversity of algal niches necessitates a comparative genomic analysis of all sequenced algal genomes. A comparison between known and putative proteins in animals, plants, fungi and algae using protein similarity networks has revealed the presence of novel metal metabolism components in Chlamydomonas including new iron and copper transporters. This analysis also supports the concept that, in terms of metal metabolism, algae from similar niches are more related to one another than to algae from the same phylogenetic clade. This article is part of a Special Issue entitled: Cell Biology of Metals.
Collapse
|
42
|
Atteia A, van Lis R, Tielens AGM, Martin WF. Anaerobic energy metabolism in unicellular photosynthetic eukaryotes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1827:210-23. [PMID: 22902601 DOI: 10.1016/j.bbabio.2012.08.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/30/2012] [Accepted: 08/05/2012] [Indexed: 12/25/2022]
Abstract
Anaerobic metabolic pathways allow unicellular organisms to tolerate or colonize anoxic environments. Over the past ten years, genome sequencing projects have brought a new light on the extent of anaerobic metabolism in eukaryotes. A surprising development has been that free-living unicellular algae capable of photoautotrophic lifestyle are, in terms of their enzymatic repertoire, among the best equipped eukaryotes known when it comes to anaerobic energy metabolism. Some of these algae are marine organisms, common in the oceans, others are more typically soil inhabitants. All these species are important from the ecological (O(2)/CO(2) budget), biotechnological, and evolutionary perspectives. In the unicellular algae surveyed here, mixed-acid type fermentations are widespread while anaerobic respiration, which is more typical of eukaryotic heterotrophs, appears to be rare. The presence of a core anaerobic metabolism among the algae provides insights into its evolutionary origin, which traces to the eukaryote common ancestor. The predicted fermentative enzymes often exhibit an amino acid extension at the N-terminus, suggesting that these proteins might be compartmentalized in the cell, likely in the chloroplast or the mitochondrion. The green algae Chlamydomonas reinhardtii and Chlorella NC64 have the most extended set of fermentative enzymes reported so far. Among the eukaryotes with secondary plastids, the diatom Thalassiosira pseudonana has the most pronounced anaerobic capabilities as yet. From the standpoints of genomic, transcriptomic, and biochemical studies, anaerobic energy metabolism in C. reinhardtii remains the best characterized among photosynthetic protists. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
Collapse
Affiliation(s)
- Ariane Atteia
- Unité de Bioénergétique et Ingénierie des Protéines-UMR 7281, CNRS-Aix-Marseille Univ, 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | | | | | | |
Collapse
|
43
|
Page MD, Allen MD, Kropat J, Urzica EI, Karpowicz SJ, Hsieh SI, Loo JA, Merchant SS. Fe sparing and Fe recycling contribute to increased superoxide dismutase capacity in iron-starved Chlamydomonas reinhardtii. THE PLANT CELL 2012; 24:2649-65. [PMID: 22685165 PMCID: PMC3406916 DOI: 10.1105/tpc.112.098962] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 05/16/2012] [Accepted: 05/24/2012] [Indexed: 05/04/2023]
Abstract
Fe deficiency is one of several abiotic stresses that impacts plant metabolism because of the loss of function of Fe-containing enzymes in chloroplasts and mitochondria, including cytochromes, FeS proteins, and Fe superoxide dismutase (FeSOD). Two pathways increase the capacity of the Chlamydomonas reinhardtii chloroplast to detoxify superoxide during Fe limitation stress. In one pathway, MSD3 is upregulated at the transcriptional level up to 10(3)-fold in response to Fe limitation, leading to synthesis of a previously undiscovered plastid-specific MnSOD whose identity we validated immunochemically. In a second pathway, the plastid FeSOD is preferentially retained over other abundant Fe proteins, heme-containing cytochrome f, diiron magnesium protoporphyrin monomethyl ester cyclase, and Fe2S2-containing ferredoxin, demonstrating prioritized allocation of Fe within the chloroplast. Maintenance of FeSOD occurs, after an initial phase of degradation, by de novo resynthesis in the absence of extracellular Fe, suggesting the operation of salvage mechanisms for intracellular recycling and reallocation.
Collapse
Affiliation(s)
- M. Dudley Page
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | | | - Janette Kropat
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | - Eugen I. Urzica
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | | | - Scott. I. Hsieh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | - Joseph A. Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | - Sabeeha S. Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| |
Collapse
|
44
|
Merchant SS, Helmann JD. Elemental economy: microbial strategies for optimizing growth in the face of nutrient limitation. Adv Microb Physiol 2012; 60:91-210. [PMID: 22633059 PMCID: PMC4100946 DOI: 10.1016/b978-0-12-398264-3.00002-4] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Microorganisms play a dominant role in the biogeochemical cycling of nutrients. They are rightly praised for their facility for fixing both carbon and nitrogen into organic matter, and microbial driven processes have tangibly altered the chemical composition of the biosphere and its surrounding atmosphere. Despite their prodigious capacity for molecular transformations, microorganisms are powerless in the face of the immutability of the elements. Limitations for specific elements, either fleeting or persisting over eons, have left an indelible trace on microbial genomes, physiology, and their very atomic composition. We here review the impact of elemental limitation on microbes, with a focus on selected genetic model systems and representative microbes from the ocean ecosystem. Evolutionary adaptations that enhance growth in the face of persistent or recurrent elemental limitations are evident from genome and proteome analyses. These range from the extreme (such as dispensing with a requirement for a hard to obtain element) to the extremely subtle (changes in protein amino acid sequences that slightly, but significantly, reduce cellular carbon, nitrogen, or sulfur demand). One near-universal adaptation is the development of sophisticated acclimation programs by which cells adjust their chemical composition in response to a changing environment. When specific elements become limiting, acclimation typically begins with an increased commitment to acquisition and a concomitant mobilization of stored resources. If elemental limitation persists, the cell implements austerity measures including elemental sparing and elemental recycling. Insights into these fundamental cellular properties have emerged from studies at many different levels, including ecology, biological oceanography, biogeochemistry, molecular genetics, genomics, and microbial physiology. Here, we present a synthesis of these diverse studies and attempt to discern some overarching themes.
Collapse
Affiliation(s)
- Sabeeha S. Merchant
- Institute for Genomics and Proteomics and Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - John D. Helmann
- Department of Microbiology, Cornell University, Ithaca, NY, 14853-8101
| |
Collapse
|
45
|
Nouet C, Motte P, Hanikenne M. Chloroplastic and mitochondrial metal homeostasis. TRENDS IN PLANT SCIENCE 2011; 16:395-404. [PMID: 21489854 DOI: 10.1016/j.tplants.2011.03.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 02/25/2011] [Accepted: 03/07/2011] [Indexed: 05/03/2023]
Abstract
Transition metal deficiency has a strong impact on the growth and survival of an organism. Indeed, transition metals, such as iron, copper, manganese and zinc, constitute essential cofactors for many key cellular functions. Both photosynthesis and respiration rely on metal cofactor-mediated electron transport chains. Chloroplasts and mitochondria are, therefore, organelles with high metal ion demand and represent essential components of the metal homeostasis network in photosynthetic cells. In this review, we describe the metal requirements of chloroplasts and mitochondria, the acclimation of their functions to metal deficiency and recent advances in our understanding of their contributions to cellular metal homeostasis, the control of the cellular redox status and the synthesis of metal cofactors.
Collapse
Affiliation(s)
- Cécile Nouet
- Functional Genomics and Plant Molecular Imaging, Center for Protein Engineering, Department of Life Sciences (B22), University of Liège, Belgium
| | | | | |
Collapse
|
46
|
Kropat J, Hong-Hermesdorf A, Casero D, Ent P, Castruita M, Pellegrini M, Merchant SS, Malasarn D. A revised mineral nutrient supplement increases biomass and growth rate in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 66:770-80. [PMID: 21309872 PMCID: PMC3101321 DOI: 10.1111/j.1365-313x.2011.04537.x] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Interest in exploiting algae as a biofuel source and the role of inorganic nutrient deficiency in inducing triacylglyceride (TAG) accumulation in cells necessitates a strategy to efficiently formulate species-specific culture media that can easily be manipulated. Using the reference organism Chlamydomonas reinhardtii, we tested the hypothesis that modeling trace element supplements after the cellular ionome would result in optimized cell growth. We determined the trace metal content of several commonly used Chlamydomonas strains in various culture conditions and developed a revised trace element solution to parallel these measurements. Comparison of cells growing in the revised supplement versus a traditional trace element solution revealed faster growth rates and higher maximum cell densities with the revised recipe. RNA-seq analysis of cultures growing in the traditional versus revised medium suggest that the variation in transcriptomes was smaller than that found between different wild-type strains grown in traditional Hutner's supplement. Visual observation did not reveal defects in cell motility or mating efficiency in the new supplement. Ni²⁺-inducible expression from the CYC6 promoter remained a useful tool, albeit with an increased requirement for Ni²⁺ because of the introduction of an EDTA buffer system in the revised medium. Other advantages include more facile preparation of trace element stock solutions, a reduction in total chemical use, a more consistent batch-to-batch formulation and long-term stability (tested up to 5 years). Under the new growth regime, we analyzed cells growing under different macro- and micronutrient deficiencies. TAG accumulation in N deficiency is comparable in the new medium. Fe and Zn deficiency also induced TAG accumulation, as suggested by Nile Red staining. This approach can be used to efficiently optimize culture conditions for other algal species to improve growth and to assay cell physiology.
Collapse
Affiliation(s)
- Janette Kropat
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
| | - Anne Hong-Hermesdorf
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
| | - David Casero
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, CA 90095-1569, USA
| | - Petr Ent
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
| | - Madeli Castruita
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, CA 90095-1569, USA
- Institutes of Genomic and Proteomics, University of California, Los Angeles, CA 90095-1569, USA
| | - Sabeeha S. Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
- Institutes of Genomic and Proteomics, University of California, Los Angeles, CA 90095-1569, USA
| | - Davin Malasarn
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
- Corresponding author: Davin Malasarn, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095, (310) 825-3661,
| |
Collapse
|
47
|
Rochaix JD. Reprint of: Regulation of photosynthetic electron transport. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:878-86. [PMID: 21605544 DOI: 10.1016/j.bbabio.2011.05.009] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 11/11/2010] [Accepted: 11/13/2010] [Indexed: 11/28/2022]
Abstract
The photosynthetic electron transport chain consists of photosystem II, the cytochrome b(6)f complex, photosystem I, and the free electron carriers plastoquinone and plastocyanin. Light-driven charge separation events occur at the level of photosystem II and photosystem I, which are associated at one end of the chain with the oxidation of water followed by electron flow along the electron transport chain and concomitant pumping of protons into the thylakoid lumen, which is used by the ATP synthase to generate ATP. At the other end of the chain reducing power is generated, which together with ATP is used for CO(2) assimilation. A remarkable feature of the photosynthetic apparatus is its ability to adapt to changes in environmental conditions by sensing light quality and quantity, CO(2) levels, temperature, and nutrient availability. These acclimation responses involve a complex signaling network in the chloroplasts comprising the thylakoid protein kinases Stt7/STN7 and Stl1/STN7 and the phosphatase PPH1/TAP38, which play important roles in state transitions and in the regulation of electron flow as well as in thylakoid membrane folding. The activity of some of these enzymes is closely connected to the redox state of the plastoquinone pool, and they appear to be involved both in short-term and long-term acclimation. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
Collapse
|
48
|
Terashima M, Specht M, Hippler M. The chloroplast proteome: a survey from the Chlamydomonas reinhardtii perspective with a focus on distinctive features. Curr Genet 2011; 57:151-68. [PMID: 21533645 DOI: 10.1007/s00294-011-0339-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 04/05/2011] [Accepted: 04/07/2011] [Indexed: 01/12/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii has emerged to be an important model organism for the study of oxygenic eukaryotic photosynthesis as well as other processes occurring in the chloroplast. However, the chloroplast proteome in C. reinhardtii has only recently been comprehensively characterized, made possible by proteomics emerging as an accessible and powerful tool over the last decade. In this review, we introduce a compiled list of 996 experimentally chloroplast-localized proteins for C. reinhardtii, stemming largely from our previous proteomic dataset comparing chloroplasts and mitochondria samples to localize proteins. In order to get a taste of some cellular functions taking place in the C. reinhardtii chloroplast, we will focus this review particularly on metabolic differences between chloroplasts of C. reinhardtii and higher plants. Areas that will be covered are photosynthesis, chlorophyll biosynthesis, carbon metabolism, fermentative metabolism, ferredoxins and ferredoxin-interacting proteins.
Collapse
Affiliation(s)
- Mia Terashima
- Department of Biology, Institute of Plant Biology and Biotechnology, University of Münster, Hindenburgplatz 55, 48143, Münster, Germany
| | | | | |
Collapse
|
49
|
Castruita M, Casero D, Karpowicz SJ, Kropat J, Vieler A, Hsieh SI, Yan W, Cokus S, Loo JA, Benning C, Pellegrini M, Merchant SS. Systems biology approach in Chlamydomonas reveals connections between copper nutrition and multiple metabolic steps. THE PLANT CELL 2011; 23:1273-92. [PMID: 21498682 PMCID: PMC3101551 DOI: 10.1105/tpc.111.084400] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 03/02/2011] [Accepted: 03/27/2011] [Indexed: 05/18/2023]
Abstract
In this work, we query the Chlamydomonas reinhardtii copper regulon at a whole-genome level. Our RNA-Seq data simulation and analysis pipeline validated a 2-fold cutoff and 10 RPKM (reads per kilobase of mappable length per million mapped reads) (~1 mRNA per cell) to reveal 63 CRR1 targets plus another 86 copper-responsive genes. Proteomic and immunoblot analyses captured 25% of the corresponding proteins, whose abundance was also dependent on copper nutrition, validating transcriptional regulation as a major control mechanism for copper signaling in Chlamydomonas. The impact of copper deficiency on the expression of several O₂-dependent enzymes included steps in lipid modification pathways. Quantitative lipid profiles indicated increased polyunsaturation of fatty acids on thylakoid membrane digalactosyldiglycerides, indicating a global impact of copper deficiency on the photosynthetic apparatus. Discovery of a putative plastid copper chaperone and a membrane protease in the thylakoid suggest a mechanism for blocking copper utilization in the chloroplast. We also found an example of copper sparing in the N assimilation pathway: the replacement of copper amine oxidase by a flavin-dependent backup enzyme. Forty percent of the targets are previously uncharacterized proteins, indicating considerable potential for new discovery in the biology of copper.
Collapse
Affiliation(s)
- Madeli Castruita
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - David Casero
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
| | - Steven J. Karpowicz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Janette Kropat
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Astrid Vieler
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Scott I. Hsieh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Weihong Yan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Shawn Cokus
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
| | - Joseph A. Loo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
- Department of Biological Chemistry, University of California, Los Angeles, California 90095
| | - Christoph Benning
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
| | - Sabeeha S. Merchant
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
- Institute of Genomics and Proteomics, University of California, Los Angeles, California 90095
- Address correspondence to
| |
Collapse
|
50
|
Ginger ML, Fritz-Laylin LK, Fulton C, Cande WZ, Dawson SC. Intermediary metabolism in protists: a sequence-based view of facultative anaerobic metabolism in evolutionarily diverse eukaryotes. Protist 2010; 161:642-71. [PMID: 21036663 PMCID: PMC3021972 DOI: 10.1016/j.protis.2010.09.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Protists account for the bulk of eukaryotic diversity. Through studies of gene and especially genome sequences the molecular basis for this diversity can be determined. Evident from genome sequencing are examples of versatile metabolism that go far beyond the canonical pathways described for eukaryotes in textbooks. In the last 2-3 years, genome sequencing and transcript profiling has unveiled several examples of heterotrophic and phototrophic protists that are unexpectedly well-equipped for ATP production using a facultative anaerobic metabolism, including some protists that can (Chlamydomonas reinhardtii) or are predicted (Naegleria gruberi, Acanthamoeba castellanii, Amoebidium parasiticum) to produce H(2) in their metabolism. It is possible that some enzymes of anaerobic metabolism were acquired and distributed among eukaryotes by lateral transfer, but it is also likely that the common ancestor of eukaryotes already had far more metabolic versatility than was widely thought a few years ago. The discussion of core energy metabolism in unicellular eukaryotes is the subject of this review. Since genomic sequencing has so far only touched the surface of protist diversity, it is anticipated that sequences of additional protists may reveal an even wider range of metabolic capabilities, while simultaneously enriching our understanding of the early evolution of eukaryotes.
Collapse
Affiliation(s)
- Michael L Ginger
- School of Health and Medicine, Division of Biomedical and Life Sciences, Lancaster University, Lancaster LA1 4YQ, UK.
| | | | | | | | | |
Collapse
|