1
|
de Jesús-Campos D, García-Ortega LF, Fimbres-Olivarría D, Herrera-Estrella L, López-Elías JA, Hayano-Kanashiro C. Transcriptomic analysis of Chaetoceros muelleri in response to different nitrogen concentrations reveals the activation of pathways to enable efficient nitrogen uptake. Gene 2024; 924:148589. [PMID: 38777108 DOI: 10.1016/j.gene.2024.148589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 05/07/2024] [Accepted: 05/17/2024] [Indexed: 05/25/2024]
Abstract
Nitrogen is the principal nutrient deficiency that increases lipids and carbohydrate content in diatoms but negatively affects biomass production. Marine diatom Chaetoceros muelleri is characterized by lipid and carbohydrate accumulation under low nitrogen concentration without affecting biomass. To elucidate the molecular effects of nitrogen concentrations, we performed an RNA-seq analysis of C. muelleri grown under four nitrogen concentrations (3.53 mM, 1.76 mM, 0.44 mM, and 0.18 mM of NaNO3). This research revealed that changes in global transcription in C. muelleri are differentially expressed by nitrogen concentration. "Energetic metabolism", "Carbohydrate metabolism" and "Lipid metabolism" pathways were identified as the most upregulated by N deficiency. Due to N limitation, alternative pathways to self-supply nitrogen employed by microalgal cells were identified. Additionally, nitrogen limitation decreased chlorophyll content and caused a greater response at the transcriptional level with a higher number of unigenes differentially expressed. By contrast, the highest N concentration (3.53 mM) recorded the lowest number of differentially expressed genes. Amt1, Nrt2, Fad2, Skn7, Wrky19, and Dgat2 genes were evaluated by RT-qPCR. In conclusion, C. muelleri modify their metabolic pathways to optimize nitrogen utilization and minimize nitrogen losses. On the other hand, the assembled transcriptome serves as the basis for metabolic engineering focused on improving the quantity and quality of the diatom for biotechnological applications. However, proteomic and metabolomic analysis is also required to compare gene expression, protein, and metabolite accumulation.
Collapse
Affiliation(s)
- Damaristelma de Jesús-Campos
- Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora, Hermosillo-Sonora CP 83000, Mexico
| | - Luis Fernando García-Ortega
- Departamento de Ingeniería Genética, Centro de Investigación y Estudios Avanzados del IPN, Irapuato-Guanajuato Zip Code 36821, Mexico
| | - Diana Fimbres-Olivarría
- Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora, Hermosillo-Sonora CP 83000, Mexico
| | - Luis Herrera-Estrella
- Institute of Genomics for Crop Abiotic Stress Tolerance, Plant and Soil Science Department, Texas Tech University, 79409 Lubbock, TX, USA; Unidad de Genómica Avanzada/LANGEBIO, Centro de Investigación y Estudios Avanzados del IPN, Irapuato-Guanajuato Zip Code 36821, Mexico
| | - José Antonio López-Elías
- Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora, Hermosillo-Sonora CP 83000, Mexico.
| | - Corina Hayano-Kanashiro
- Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora, Hermosillo-Sonora CP 83000, Mexico.
| |
Collapse
|
2
|
Dorrell RG, Zhang Y, Liang Y, Gueguen N, Nonoyama T, Croteau D, Penot-Raquin M, Adiba S, Bailleul B, Gros V, Pierella Karlusich JJ, Zweig N, Fernie AR, Jouhet J, Maréchal E, Bowler C. Complementary environmental analysis and functional characterization of lower glycolysis-gluconeogenesis in the diatom plastid. THE PLANT CELL 2024; 36:3584-3610. [PMID: 38842420 PMCID: PMC11371179 DOI: 10.1093/plcell/koae168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/14/2024] [Accepted: 05/30/2024] [Indexed: 06/07/2024]
Abstract
Organic carbon fixed in chloroplasts through the Calvin-Benson-Bassham Cycle can be diverted toward different metabolic fates, including cytoplasmic and mitochondrial respiration, gluconeogenesis, and synthesis of diverse plastid metabolites via the pyruvate hub. In plants, pyruvate is principally produced via cytoplasmic glycolysis, although a plastid-targeted lower glycolytic pathway is known to exist in non-photosynthetic tissue. Here, we characterized a lower plastid glycolysis-gluconeogenesis pathway enabling the direct interconversion of glyceraldehyde-3-phosphate and phospho-enol-pyruvate in diatoms, ecologically important marine algae distantly related to plants. We show that two reversible enzymes required to complete diatom plastid glycolysis-gluconeogenesis, Enolase and bis-phosphoglycerate mutase (PGAM), originated through duplications of mitochondria-targeted respiratory isoforms. Through CRISPR-Cas9 mutagenesis, integrative 'omic analyses, and measured kinetics of expressed enzymes in the diatom Phaeodactylum tricornutum, we present evidence that this pathway diverts plastid glyceraldehyde-3-phosphate into the pyruvate hub, and may also function in the gluconeogenic direction. Considering experimental data, we show that this pathway has different roles dependent in particular on day length and environmental temperature, and show that the cpEnolase and cpPGAM genes are expressed at elevated levels in high-latitude oceans where diatoms are abundant. Our data provide evolutionary, meta-genomic, and functional insights into a poorly understood yet evolutionarily recurrent plastid metabolic pathway.
Collapse
Affiliation(s)
- Richard G Dorrell
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- CNRS Research Federation for the study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
- Laboratory of Computational and Quantitative Biology (LCQB), Institut de Biologie Paris-Seine (IBPS), CNRS, INSERM, Sorbonne Université, Paris 75005, France
| | - Youjun Zhang
- Department of Plant Metabolomics, Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Central Plant Metabolism Group, Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yue Liang
- Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
- Laboratory for Marine Mineral Resources, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Nolwenn Gueguen
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, University Grenoble Alpes, CEA, INRAE, IRIG, 38000 Grenoble, France
| | - Tomomi Nonoyama
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- Division of Biotechnology and Life Science, Institute of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Dany Croteau
- Institut de Biologie Physico-Chimique (IBPC), Université PSL, Paris 75005, France
| | - Mathias Penot-Raquin
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- CNRS Research Federation for the study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
- Laboratory of Computational and Quantitative Biology (LCQB), Institut de Biologie Paris-Seine (IBPS), CNRS, INSERM, Sorbonne Université, Paris 75005, France
| | - Sandrine Adiba
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
| | - Benjamin Bailleul
- Institut de Biologie Physico-Chimique (IBPC), Université PSL, Paris 75005, France
| | - Valérie Gros
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, University Grenoble Alpes, CEA, INRAE, IRIG, 38000 Grenoble, France
| | - Juan José Pierella Karlusich
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- CNRS Research Federation for the study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Nathanaël Zweig
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- CNRS Research Federation for the study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Alisdair R Fernie
- Department of Plant Metabolomics, Center of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
- Central Plant Metabolism Group, Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
| | - Juliette Jouhet
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, University Grenoble Alpes, CEA, INRAE, IRIG, 38000 Grenoble, France
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire et Végétale, CNRS, University Grenoble Alpes, CEA, INRAE, IRIG, 38000 Grenoble, France
| | - Chris Bowler
- Institut de Biologie de l’ENS (IBENS), Département de Biologie, École Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
- CNRS Research Federation for the study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| |
Collapse
|
3
|
Santin A, Russo MT, de Los Ríos LM, Chiurazzi M, d'Alcalà MR, Lacombe B, Ferrante MI, Rogato A. The tonoplast localized protein PtNPF1 participates in the regulation of nitrogen response in diatoms. THE NEW PHYTOLOGIST 2024; 241:1592-1604. [PMID: 38084038 DOI: 10.1111/nph.19461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 11/21/2023] [Indexed: 01/26/2024]
Abstract
Diatoms are a highly successful group of phytoplankton, well adapted also to oligotrophic environments and capable of handling nutrient fluctuations in the ocean, particularly nitrate. The presence of a large vacuole is an important trait contributing to their adaptive features. It confers diatoms the ability to accumulate and store nutrients, such as nitrate, when they are abundant outside and then to reallocate them into the cytosol to meet deficiencies, in a process called luxury uptake. The molecular mechanisms that regulate these nitrate fluxes are still not known in diatoms. In this work, we provide new insights into the function of Phaeodactylum tricornutum NPF1, a putative low-affinity nitrate transporter. To accomplish this, we generated overexpressing strains and CRISPR/Cas9 loss-of-function mutants. Microscopy observations confirmed predictions that PtNPF1 is localized on the vacuole membrane. Furthermore, functional characterizations performed on knock-out mutants revealed a transient growth delay phenotype linked to altered nitrate uptake. Together, these results allowed us to hypothesize that PtNPF1 is presumably involved in modulating intracellular nitrogen fluxes, managing intracellular nutrient availability. This ability might allow diatoms to fine-tune the assimilation, storage and reallocation of nitrate, conferring them a strong advantage in oligotrophic environments.
Collapse
Affiliation(s)
- Anna Santin
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, 80121, Italy
| | | | - Laura Morales de Los Ríos
- Institute for Plant Science of Montpellier (IPSiM), University of Montpellier, CNRS, INRAE, Montpellier SupAgro, Place Pierre Viala 2, Montpellier, 34060, France
| | - Maurizio Chiurazzi
- Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, Naples, 80131, Italy
| | | | - Benoît Lacombe
- Institute for Plant Science of Montpellier (IPSiM), University of Montpellier, CNRS, INRAE, Montpellier SupAgro, Place Pierre Viala 2, Montpellier, 34060, France
| | - Maria Immacolata Ferrante
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, 80121, Italy
- National Institute of Oceanography and Applied Geophysics, Trieste, 34010, Italy
| | - Alessandra Rogato
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, 80121, Italy
- Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, Naples, 80131, Italy
| |
Collapse
|
4
|
Pan Y, Zhang W, Wang X, Jouhet J, Maréchal E, Liu J, Xia XQ, Hu H. Allele-dependent expression and functionality of lipid enzyme phospholipid:diacylglycerol acyltransferase affect diatom carbon storage and growth. PLANT PHYSIOLOGY 2024; 194:1024-1040. [PMID: 37930282 DOI: 10.1093/plphys/kiad581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 09/06/2023] [Accepted: 10/11/2023] [Indexed: 11/07/2023]
Abstract
In the acyl-CoA-independent pathway of triacylglycerol (TAG) synthesis unique to plants, fungi, and algae, TAG formation is catalyzed by the enzyme phospholipid:diacylglycerol acyltransferase (PDAT). The unique PDAT gene of the model diatom Phaeodactylum tricornutum strain CCMP2561 boasts 47 single nucleotide variants within protein coding regions of the alleles. To deepen our understanding of TAG synthesis, we observed the allele-specific expression of PDAT by the analysis of 87 published RNA-sequencing (RNA-seq) data and experimental validation. The transcription of one of the two PDAT alleles, Allele 2, could be specifically induced by decreasing nitrogen concentrations. Overexpression of Allele 2 in P. tricornutum substantially enhanced the accumulation of TAG by 44% to 74% under nutrient stress; however, overexpression of Allele 1 resulted in little increase of TAG accumulation. Interestingly, a more serious growth inhibition was observed in the PDAT Allele 1 overexpression strains compared with Allele 2 counterparts. Heterologous expression in yeast (Saccharomyces cerevisiae) showed that enzymes encoded by PDAT Allele 2 but not Allele 1 had TAG biosynthetic activity, and 7 N-terminal and 3 C-terminal amino acid variants between the 2 allele-encoded proteins substantially affected enzymatic activity. P. tricornutum PDAT, localized in the innermost chloroplast membrane, used monogalactosyldiacylglycerol and phosphatidylcholine as acyl donors as demonstrated by the increase of the 2 lipids in PDAT knockout lines, which indicated a common origin in evolution with green algal PDATs. Our study reveals unequal roles among allele-encoded PDATs in mediating carbon storage and growth in response to nitrogen stress and suggests an unsuspected strategy toward lipid and biomass improvement for biotechnological purposes.
Collapse
Affiliation(s)
- Yufang Pan
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wanting Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiaofei Wang
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing 100871, China
| | - Juliette Jouhet
- Laboratoire de Physiologie Cellulaire Végétale, Université Grenoble Alpes, CEA, CNRS, INRA, IRIG-LPCV, Grenoble Cedex 9 38054, France
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire Végétale, Université Grenoble Alpes, CEA, CNRS, INRA, IRIG-LPCV, Grenoble Cedex 9 38054, France
| | - Jin Liu
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing 100871, China
| | - Xiao-Qin Xia
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanhua Hu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| |
Collapse
|
5
|
Russo MT, Rogato A, Jaubert M, Karas BJ, Falciatore A. Phaeodactylum tricornutum: An established model species for diatom molecular research and an emerging chassis for algal synthetic biology. JOURNAL OF PHYCOLOGY 2023; 59:1114-1122. [PMID: 37975560 DOI: 10.1111/jpy.13400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 10/05/2023] [Indexed: 11/19/2023]
Abstract
Diatoms are prominent and highly diverse microalgae in aquatic environments. Compared with other diatom species, Phaeodactylum tricornutum is an "atypical diatom" displaying three different morphotypes and lacking the usual silica shell. Despite being of limited ecological relevance, its ease of growth in the laboratory and well-known physiology, alongside the steady increase in genome-enabled information coupled with effective tools for manipulating gene expression, have meant it has gained increased recognition as a powerful experimental model for molecular research on diatoms. We here present a brief overview of how over the last 25 years P. tricornutum has contributed to the unveiling of fundamental aspects of diatom biology, while also emerging as a new tool for algal process engineering and synthetic biology.
Collapse
Affiliation(s)
- Monia T Russo
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Alessandra Rogato
- Institute of Biosciences and Bioresources, National Research Council, IBBR-CNR, Naples, Italy
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Naples, Italy
| | - Marianne Jaubert
- UMR7141 Laboratoire de Biologie du chloroplaste et perception de la lumière chez les micro-algues, Institut de Biologie Physico-Chimique, Paris, France
| | - Bogumil J Karas
- Department of Biochemistry, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
| | - Angela Falciatore
- UMR7141 Laboratoire de Biologie du chloroplaste et perception de la lumière chez les micro-algues, Institut de Biologie Physico-Chimique, Paris, France
| |
Collapse
|
6
|
Garza EA, Bielinski VA, Espinoza JL, Orlandi K, Alfaro JR, Bolt TM, Beeri K, Weyman PD, Dupont CL. Validating a Promoter Library for Application in Plasmid-Based Diatom Genetic Engineering. ACS Synth Biol 2023; 12:3215-3228. [PMID: 37857380 PMCID: PMC10661051 DOI: 10.1021/acssynbio.3c00163] [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: 03/21/2023] [Indexed: 10/21/2023]
Abstract
While diatoms are promising synthetic biology platforms, there currently exists a limited number of validated genetic regulatory parts available for genetic engineering. The standard method for diatom transformation, nonspecific introduction of DNA into chromosomes via biolistic particle bombardment, is low throughput and suffers from clonal variability and epigenetic effects. Recent developments in diatom engineering have demonstrated that autonomously replicating episomal plasmids serve as stable expression platforms for diverse gene expression technologies. These plasmids are delivered via bacterial conjugation and, when combined with modular DNA assembly technologies, provide a flexibility and speed not possible with biolistic-mediated strain generation. In order to expand the current toolbox for plasmid-based engineering in the diatom Phaeodactylum tricornutum, a conjugation-based forward genetics screen for promoter discovery was developed, and application to a diatom genomic DNA library defined 252 P. tricornutum promoter elements. From this library, 40 promoter/terminator pairs were delivered via conjugation on episomal plasmids, characterized in vivo, and ranked across 4 orders of magnitude difference in reporter gene expression levels.
Collapse
Affiliation(s)
- Erin A. Garza
- J. Craig Venter Institute, La Jolla, California 92037, United States
| | | | - Josh L. Espinoza
- J. Craig Venter Institute, La Jolla, California 92037, United States
| | | | | | | | | | | | | |
Collapse
|
7
|
Brunson JK, Thukral M, Ryan JP, Anderson CR, Kolody BC, James C, Chavez FP, Leaw CP, Rabines AJ, Venepally P, Zheng H, Kudela RM, Smith GJ, Moore BS, Allen AE. Molecular Forecasting of Domoic Acid during a Pervasive Toxic Diatom Bloom. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.02.565333. [PMID: 37961417 PMCID: PMC10635071 DOI: 10.1101/2023.11.02.565333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
In 2015, the largest recorded harmful algal bloom (HAB) occurred in the Northeast Pacific, causing nearly 100 million dollars in damages to fisheries and killing many protected marine mammals. Dominated by the toxic diatom Pseudo-nitzschia australis , this bloom produced high levels of the neurotoxin domoic acid (DA). Through molecular and transcriptional characterization of 52 near-weekly phytoplankton net-tow samples collected at a bloom hotspot in Monterey Bay, California, we identified active transcription of known DA biosynthesis ( dab ) genes from the three identified toxigenic species, including P. australis as the primary origin of toxicity. Elevated expression of silicon transporters ( sit1 ) during the bloom supports the previously hypothesized role of dissolved silica (Si) exhaustion in contributing to bloom physiology and toxicity. We find that co-expression of the dabA and sit1 genes serves as a robust predictor of DA one week in advance, potentially enabling the forecasting of DA-producing HABs. We additionally present evidence that low levels of iron could have co-limited the diatom population along with low Si. Iron limitation represents a previously unrecognized driver of both toxin production and ecological success of the low iron adapted Pseudo-nitzschia genus during the 2015 bloom, and increasing pervasiveness of iron limitation may fuel the escalating magnitude and frequency of toxic Pseudo-nitzschia blooms globally. Our results advance understanding of bloom physiology underlying toxin production, bloom prediction, and the impact of global change on toxic blooms. Significance Pseudo-nitzschia diatoms form oceanic harmful algal blooms that threaten human health through production of the neurotoxin domoic acid (DA). DA biosynthetic gene expression is hypothesized to control DA production in the environment, yet what regulates expression of these genes is yet to be discovered. In this study, we uncovered expression of DA biosynthesis genes by multiple toxigenic Pseudo-nitzschia species during an economically impactful bloom along the North American West Coast, and identified genes that predict DA in advance of its production. We discovered that iron and silica co-limitation restrained the bloom and likely promoted toxin production. This work suggests that increasing iron limitation due to global change may play a previously unrecognized role in driving bloom frequency and toxicity.
Collapse
|
8
|
Ban H, Sato S, Yoshikawa S, Yamada K, Nakamura Y, Ichinomiya M, Sato N, Blanc-Mathieu R, Endo H, Kuwata A, Ogata H. Genome analysis of Parmales, the sister group of diatoms, reveals the evolutionary specialization of diatoms from phago-mixotrophs to photoautotrophs. Commun Biol 2023; 6:697. [PMID: 37420035 PMCID: PMC10328945 DOI: 10.1038/s42003-023-05002-x] [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: 10/13/2022] [Accepted: 05/31/2023] [Indexed: 07/09/2023] Open
Abstract
The order Parmales (class Bolidophyceae) is a minor group of pico-sized eukaryotic marine phytoplankton that contains species with cells surrounded by silica plates. Previous studies revealed that Parmales is a member of ochrophytes and sister to diatoms (phylum Bacillariophyta), the most successful phytoplankton group in the modern ocean. Therefore, parmalean genomes can serve as a reference to elucidate both the evolutionary events that differentiated these two lineages and the genomic basis for the ecological success of diatoms vs. the more cryptic lifestyle of parmaleans. Here, we compare the genomes of eight parmaleans and five diatoms to explore their physiological and evolutionary differences. Parmaleans are predicted to be phago-mixotrophs. By contrast, diatoms have lost genes related to phagocytosis, indicating the ecological specialization from phago-mixotrophy to photoautotrophy in their early evolution. Furthermore, diatoms show significant enrichment in gene sets involved in nutrient uptake and metabolism, including iron and silica, in comparison with parmaleans. Overall, our results suggest a strong evolutionary link between the loss of phago-mixotrophy and specialization to a silicified photoautotrophic life stage early in diatom evolution after diverging from the Parmales lineage.
Collapse
Affiliation(s)
- Hiroki Ban
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Shinya Sato
- Department of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuen-cho, Obama City, Fukui, 917-0003, Japan
| | - Shinya Yoshikawa
- Department of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuen-cho, Obama City, Fukui, 917-0003, Japan
| | - Kazumasa Yamada
- Department of Marine Science and Technology, Fukui Prefectural University, 1-1 Gakuen-cho, Obama City, Fukui, 917-0003, Japan
| | - Yoji Nakamura
- Bioinformatics and Biosciences Division, Fisheries Stock Assessment Center, Fisheries Resources Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fuku-ura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan
| | - Mutsuo Ichinomiya
- Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto, 862-8502, Japan
| | - Naoki Sato
- Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo, 153-8902, Japan
| | - Romain Blanc-Mathieu
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
- Laboratoire de Physiologie Cellulaire & Végétale, CEA, Univ. Grenoble Alpes, CNRS, INRA, IRIG, Grenoble, France
| | - Hisashi Endo
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Akira Kuwata
- Shiogama field station, Fisheries Resources Institute, Japan Fisheries Research and Education Agency, 3-27-5 Shinhama-cho, Shiogama, Miyagi, Japan.
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.
| |
Collapse
|
9
|
Kang W, Sun S, Hu X. Microplastics trigger the Matthew effect on nitrogen assimilation in marine diatoms at an environmentally relevant concentration. WATER RESEARCH 2023; 233:119762. [PMID: 36841163 DOI: 10.1016/j.watres.2023.119762] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Microplastics (MPs, diameter <5 mm) are widely distributed on Earth, especially in the oceans. Diatoms account for ∼40% of marine primary productivity and affect the global biogeochemical cycles of macroelements. However, the effects of MPs on marine nitrogen cycling remain poorly understood, particularly comparisons between nitrogen-replete and nitrogen-limited conditions. We found that MPs trigger the Matthew effect on nitrogen assimilation in diatoms, where MPs inhibited nitrogen assimilation under nitrogen-limited conditions while enhancing nitrogen metabolism under nitrogen-replete conditions in Phaeodactylum tricornutum. Nitrate reductase (NR) and nitrite reductase (NIR) are upregulated, but nitrate transporter (NRT) and glutamine synthetase (GS) are downregulated by MPs under nitrogen-limited conditions. In contrast, NR, NIR, and GS are all upregulated by MPs under nitrogen-replete conditions. MPs accelerate nitrogen anabolic processes with an increase in the accumulation of carbohydrates by 80.7 ± 7.9% and enhance the activities of key nitrogen-metabolizing enzymes (8.20-44.90%) under nitrogen-replete conditions. In contrast, the abundance of carbohydrates decreases by 22.0-34.4%, and NRT activity is inhibited by 79.0-86.5% in nitrogen-limited algae exposed to MPs. Metabolomic and transcriptomic analyses were performed to further explore the molecular mechanisms of reprogrammed nitrogen assimilation, including carbon metabolism, nitrogen transport and ammonia assimilation. The aforementioned spatial redistribution (e.g., the Matthew effect between nitrogen-replete and -limited conditions) of nitrogen assimilation highlights the potential risks of MP contamination in the ocean.
Collapse
Affiliation(s)
- Weilu Kang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Shan Sun
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Xiangang Hu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
| |
Collapse
|
10
|
Yin W, Hu H. CRISPR/Cas9-Mediated Genome Editing via Homologous Recombination in a Centric Diatom Chaetoceros muelleri. ACS Synth Biol 2023; 12:1287-1296. [PMID: 37031406 DOI: 10.1021/acssynbio.3c00051] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2023]
Abstract
Chaetoceros, the most abundant genus of marine planktonic diatoms, can be used in mariculture. An effective genetic transformation system with a short transformation period was established in Chaetoceros muelleri by electroporation in our previous study. In this study, a sequence-specific clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 vector applicable for C. muelleri was constructed, and the expressions of sgRNA, resistance gene, and Cas9 gene were driven by the endogenous promoters U6, acetyl-CoA acetyltransferase, and fucoxanthin chlorophyll a/c binding protein, respectively, in the vector. Nitrate reductase (NR) and urease (URE) genes were edited in C. muelleri, and the NR knockout and NR/URE double-knockout lines displayed the strict auxotrophic phenotype. In addition, the DNA double-strand break was repaired by homologous recombination when a donor DNA was introduced. CRISPR/Cas9 technology was successfully applied to C. muelleri with an editing efficiency of up to 86%, providing a molecular tool for the study of basic biology in C. muelleri and its synthetic biology applications.
Collapse
Affiliation(s)
- Wenxiu Yin
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hanhua Hu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| |
Collapse
|
11
|
Brownlee C, Helliwell KE, Meeda Y, McLachlan D, Murphy EA, Wheeler GL. Regulation and integration of membrane transport in marine diatoms. Semin Cell Dev Biol 2023; 134:79-89. [PMID: 35305902 DOI: 10.1016/j.semcdb.2022.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/18/2022] [Accepted: 03/04/2022] [Indexed: 12/27/2022]
Abstract
Diatoms represent one of the most successful groups of marine phytoplankton and are major contributors to ocean biogeochemical cycling. They have colonized marine, freshwater and ice environments and inhabit all regions of the World's oceans, from poles to tropics. Their success is underpinned by a remarkable ability to regulate their growth and metabolism during nutrient limitation and to respond rapidly when nutrients are available. This requires precise regulation of membrane transport and nutrient acquisition mechanisms, integration of nutrient sensing mechanisms and coordination of different transport pathways. This review outlines transport mechanisms involved in acquisition of key nutrients (N, C, P, Si, Fe) by marine diatoms, illustrating their complexity, sophistication and multiple levels of control.
Collapse
Affiliation(s)
- Colin Brownlee
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Ocean and Earth Sciences, University of Southampton, Southampton SO14 3ZH, UK
| | - Katherine E Helliwell
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Yasmin Meeda
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Deirdre McLachlan
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Eleanor A Murphy
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Glen L Wheeler
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| |
Collapse
|
12
|
NmrA acts as a positive regulator of nitrate assimilation in Phaeodactylum tricornutum. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
13
|
Zhou L, Gao S, Yang W, Wu S, Huan L, Xie X, Wang X, Lin S, Wang G. Transcriptomic and metabolic signatures of diatom plasticity to light fluctuations. PLANT PHYSIOLOGY 2022; 190:2295-2314. [PMID: 36149329 PMCID: PMC9706478 DOI: 10.1093/plphys/kiac455] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 09/09/2022] [Indexed: 06/01/2023]
Abstract
Unlike in terrestrial and freshwater ecosystems, light fields in oceans fluctuate due to both horizontal current and vertical mixing. Diatoms thrive and dominate the phytoplankton community in these fluctuating light fields. However, the molecular mechanisms that regulate diatom acclimation and adaptation to light fluctuations are poorly understood. Here, we performed transcriptome sequencing, metabolome profiling, and 13C-tracer labeling on the model diatom Phaeodactylum tricornutum. The diatom acclimated to constant light conditions was transferred to six different light conditions, including constant light (CL5d), short-term (1 h) high light (sHL1h), and short-term (1 h) and long-term (5 days) mild or severe light fluctuation conditions (mFL1h, sFL1h, mFL5d, and sFL5d) that mimicked land and ocean light levels. We identified 2,673 transcripts (25% of the total expressed genes) expressed differentially under different fluctuating light regimes. We also identified 497 transcription factors, 228 not reported previously, which exhibited higher expression under light fluctuations, including 7 with a light-sensitive PAS domain (Per-period circadian protein, Arnt-aryl hydrocarbon receptor nuclear translocator protein, Sim-single-minded protein) and 10 predicted to regulate genes related to light-harvesting complex proteins. Our data showed that prolonged preconditioning in severe light fluctuation enhanced photosynthesis in P. tricornutum under this condition, as evidenced by increased oxygen evolution accompanied by the upregulation of Rubisco and light-harvesting proteins. Furthermore, severe light fluctuation diverted the metabolic flux of assimilated carbon preferentially toward fatty acid storage over sugar and protein. Our results suggest that P. tricornutum use a series of complex and different responsive schemes in photosynthesis and carbon metabolism to optimize their growth under mild and severe light fluctuations. These insights underscore the importance of using more intense conditions when investigating the resilience of phytoplankton to light fluctuations.
Collapse
Affiliation(s)
- Lu Zhou
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- College of Earth Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shan Gao
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Wenting Yang
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Songcui Wu
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Li Huan
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xiujun Xie
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xulei Wang
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Senjie Lin
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, USA
| | - Guangce Wang
- Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| |
Collapse
|
14
|
Nitrogen and Iron Availability Drive Metabolic Remodeling and Natural Selection of Diverse Phytoplankton during Experimental Upwelling. mSystems 2022; 7:e0072922. [PMID: 36036504 PMCID: PMC9599627 DOI: 10.1128/msystems.00729-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Nearly half of carbon fixation and primary production originates from marine phytoplankton, and much of it occurs in episodic blooms in upwelling regimes. Here, we simulated blooms limited by nitrogen and iron by incubating Monterey Bay surface waters with subnutricline waters and inorganic nutrients and measured the whole-community transcriptomic response during mid- and late-bloom conditions. Cell counts revealed that centric and pennate diatoms (largely Pseudo-nitzschia and Chaetoceros spp.) were the major blooming taxa, but dinoflagellates, prasinophytes, and prymnesiophytes also increased. Viral mRNA significantly increased in late bloom and likely played a role in the bloom's demise. We observed conserved shifts in the genetic similarity of phytoplankton populations to cultivated strains, indicating adaptive population-level changes in community composition. Additionally, the density of single nucleotide variants (SNVs) declined in late-bloom samples for most taxa, indicating a loss of intraspecific diversity as a result of competition and a selective sweep of adaptive alleles. We noted differences between mid- and late-bloom metabolism and differential regulation of light-harvesting complexes (LHCs) under nutrient stress. While most LHCs are diminished under nutrient stress, we showed that diverse taxa upregulated specialized, energy-dissipating LHCs in low iron. We also suggest the relative expression of NRT2 compared to the expression of GSII as a marker of cellular nitrogen status and the relative expression of iron starvation-induced protein genes (ISIP1, ISIP2, and ISIP3) compared to the expression of the thiamine biosynthesis gene (thiC) as a marker of iron status in natural diatom communities. IMPORTANCE Iron and nitrogen are the nutrients that most commonly limit phytoplankton growth in the world's oceans. The utilization of these resources by phytoplankton sets the biomass available to marine systems and is of particular interest in high-nutrient, low-chlorophyll (HNLC) coastal fisheries. Previous research has described the biogeography of phytoplankton in HNLC regions and the transcriptional responses of representative taxa to nutrient limitation. However, the differential transcriptional responses of whole phytoplankton communities to iron and nitrogen limitation has not been previously described, nor has the selective pressure that these competitive bloom environments exert on major players. In addition to describing changes in the physiology of diverse phytoplankton, we suggest practical indicators of cellular nitrogen and iron status for future monitoring.
Collapse
|
15
|
Vasilev J, Mix AK, Heimerl T, Maier UG, Moog D. Inferred Subcellular Localization of Peroxisomal Matrix Proteins of Guillardia theta Suggests an Important Role of Peroxisomes in Cryptophytes. FRONTIERS IN PLANT SCIENCE 2022; 13:889662. [PMID: 35783940 PMCID: PMC9244630 DOI: 10.3389/fpls.2022.889662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Peroxisomes participate in several important metabolic processes in eukaryotic cells, such as the detoxification of reactive oxygen species (ROS) or the degradation of fatty acids by β-oxidation. Recently, the presence of peroxisomes in the cryptophyte Guillardia theta and other "chromalveolates" was revealed by identifying proteins for peroxisomal biogenesis. Here, we investigated the subcellular localization of candidate proteins of G. theta in the diatom Phaeodactylum tricornutum, either possessing a putative peroxisomal targeting signal type 1 (PTS1) sequence or factors lacking a peroxisomal targeting signal but known to be involved in β-oxidation. Our results indicate important contributions of the peroxisomes of G. theta to the carbohydrate, ether phospholipid, nucleotide, vitamin K, ROS, amino acid, and amine metabolisms. Moreover, our results suggest that in contrast to many other organisms, the peroxisomes of G. theta are not involved in the β-oxidation of fatty acids, which exclusively seems to occur in the cryptophyte's mitochondria.
Collapse
Affiliation(s)
- Jana Vasilev
- Laboratory for Cell Biology, Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Ann-Kathrin Mix
- Laboratory for Cell Biology, Department of Biology, Philipps-University Marburg, Marburg, Germany
| | - Thomas Heimerl
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Uwe G. Maier
- Laboratory for Cell Biology, Department of Biology, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Daniel Moog
- Laboratory for Cell Biology, Department of Biology, Philipps-University Marburg, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| |
Collapse
|
16
|
Kang W, Yu F, Wang S, Hu X. Marine Colloids Promote the Adaptation of Diatoms to Nitrate Contamination by Directional Electron Transfer. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:5694-5705. [PMID: 35435662 DOI: 10.1021/acs.est.2c00044] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nitrate contamination from human activities (e.g., domestic pollution, livestock breeding, and fertilizer application) threatens marine ecosystems and net primary productivity. As the main component of primary productivity, diatoms can adapt to high nitrate environments, but the mechanism is unclear. We found that electron transfer from marine colloids to diatoms enhances nitrogen uptake and assimilation under visible-light irradiation, providing a new pathway for nitrogen adaptation. Under irradiation, marine colloids exhibit semiconductor properties (e.g., the separation of electron-hole pairs) and can trigger the generation of free electrons and singlet oxygen. They also exhibit electron acceptor and donor properties, with the former being stronger than the latter, reacting with polysaccharides in extracellular polymeric substances (EPSs) under high nitrogen stress, enhancing the elasticity and permeability of cells, and promoting nitrogen assimilation and electron transfer to marine diatom EPSs. Electron transfer promotes extracellular-to-intracellular nitrate transport by upregulating membrane nitrate transporters and nitrate reductase. The upregulation of anion transport genes and unsaturated fatty acids contributes to nitrogen assimilation. We estimate that colloids may increase the nitrate uptake efficiency of marine diatoms by 10.5-82.2%. These findings reveal a mechanism by which diatoms adapt to nitrate contamination and indicate a low-cost strategy to control marine pollution.
Collapse
Affiliation(s)
- Weilu Kang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Fubo Yu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Shuting Wang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Xiangang Hu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| |
Collapse
|
17
|
Ren J, Yang X, Zhang N, Feng L, Ma C, Wang Y, Yang Z, Zhao J. Melatonin alleviates aluminum-induced growth inhibition by modulating carbon and nitrogen metabolism, and reestablishing redox homeostasis in Zea mays L. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127159. [PMID: 34537633 DOI: 10.1016/j.jhazmat.2021.127159] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 08/30/2021] [Accepted: 09/04/2021] [Indexed: 05/11/2023]
Abstract
Melatonin, a regulatory molecule, performs pleiotropic functions in plants, including aluminum (Al) stress mitigation. Here, we conducted transcriptomic and physiological analyses to identify metabolic processes associated with the alleviated Al-induced growth inhibition of the melatonin-treated (MT) maize (Zea mays L.) seedlings. Melatonin decreased Al concentration in maize roots and leaves under Al stress. Al stress reduced the total dry weight (DW) by 41.2% after 7 days of treatment. By contrast, the total DW was decreased by only 19.4% in MT plants. According to RNA-Seq, enzyme activity, and metabolite content data, MT plants exhibited a higher level of relatively stable carbon and nitrogen metabolism than non-treated (NT) plants. Under Al stress, MT plants showed higher photosynthetic rate and sucrose content by 29.9% and 20.5% than NT plants, respectively. Similarly, the nitrate reductase activity and protein content of MT plants were 34.0% and 15.0% higher than those of NT plants, respectively. Furthermore, exogenous supply of melatonin mitigated Al-induced oxidative stress. Overall, our results suggest that melatonin alleviates aluminum-induced growth inhibition through modulating carbon and nitrogen metabolism, and reestablishing redox homeostasis in maize. Graphical Abstarct.
Collapse
Affiliation(s)
- Jianhong Ren
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiaoxiao Yang
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ning Zhang
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Lu Feng
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Chunying Ma
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China
| | - Yuling Wang
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China
| | - Zhenping Yang
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China.
| | - Juan Zhao
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi 030800, China.
| |
Collapse
|
18
|
Abassi S, Ki JS. Increased nitrate concentration differentially affects cell growth and expression of nitrate transporter and other nitrogen-related genes in the harmful dinoflagellate Prorocentrum minimum. CHEMOSPHERE 2022; 288:132526. [PMID: 34637868 DOI: 10.1016/j.chemosphere.2021.132526] [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: 08/11/2021] [Revised: 09/29/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
The molecular mechanisms through which dinoflagellates adapt to nitrate fluctuations in aquatic environments remain poorly understood. Here, we sequenced the full-length cDNA of a nitrate transporter (NRT) gene from the harmful marine dinoflagellate Prorocentrum minimum Schiller. The cDNA length was 2431 bp. It encoded a 529-amino acid protein, which was phylogenetically clustered with proteins from other dinoflagellates. Nitrate supply promoted cell growth up to a certain concentration (∼1.76 mM) but inhibited it at higher concentrations. Interestingly, at the inhibitory concentrations, nitrite levels in the medium were considerably increased. Nitrate concentration affected the expression of PmNRT, nitrite transporter (PmNiRT), nitrate reductase (PmNR), and nitrite reductase (PmNiR). Specifically, PmNRT was upregulated after 24 h, with ∼6-fold change compared with the control level, in both nitrate-depleted and nitrate-repleted cultures. In addition, PmNR transcript levels increased to the maximum of 4-fold at 48 h but decreased thereafter. In contrast, PmNiR levels remained unchanged in both nitrate-repleted and nitrate-depleted cultures. Therefore, P. minimum likely copes with nitrate fluctuations in its environment by regulating a set of genes responsible for nitrate uptake.
Collapse
Affiliation(s)
- Sofia Abassi
- Department of Biotechnology, Sangmyung University, Seoul, 03016, South Korea
| | - Jang-Seu Ki
- Department of Biotechnology, Sangmyung University, Seoul, 03016, South Korea.
| |
Collapse
|
19
|
Kassaw TK, Paton AJ, Peers G. Episome-Based Gene Expression Modulation Platform in the Model Diatom Phaeodactylum tricornutum. ACS Synth Biol 2022; 11:191-204. [PMID: 35015507 DOI: 10.1021/acssynbio.1c00367] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Chemically inducible gene expression systems have been an integral part of the advanced synthetic genetic circuit design and are employed for precise dynamic control over genetically engineered traits. However, the current systems for controlling transgene expression in most algae are limited to endogenous promoters that respond to different environmental factors. We developed a highly efficient, tunable, and reversible episome-based transcriptional control system in the model diatom alga, Phaeodactylum tricornutum. We assessed the time- and dose-response dynamics of each expression system using a reporter protein (eYFP) as a readout. Using our circuit configuration, we found two inducible expression systems with a high dynamic range and confirmed the suitability of an episome expression platform for synthetic biological applications in diatoms. These systems are controlled by the presence of β-estradiol and digoxin. Addition of either chemical to transgenic strains activates transcription with a dynamic range of up to ∼180-fold and ∼90-fold, respectively. We demonstrated that our episome-based transcriptional control systems are tunable and reversible in a dose- and time-dependent manner. Using droplet digital polymerase chain reaction (PCR), we also confirmed that inducer-dependent transcriptional activation starts within minutes of inducer application without any detectable transcript in the uninduced controls. The system described here expands the molecular and synthetic biology toolkits in algae and will facilitate future gene discovery and metabolic engineering efforts.
Collapse
Affiliation(s)
- Tessema K. Kassaw
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Andrew J. Paton
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Graham Peers
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, United States
| |
Collapse
|
20
|
Scarsini M, Thiriet-Rupert S, Veidl B, Mondeguer F, Hu H, Marchand J, Schoefs B. The Transition Toward Nitrogen Deprivation in Diatoms Requires Chloroplast Stand-By and Deep Metabolic Reshuffling. FRONTIERS IN PLANT SCIENCE 2022; 12:760516. [PMID: 35126407 PMCID: PMC8811913 DOI: 10.3389/fpls.2021.760516] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/19/2021] [Indexed: 06/14/2023]
Abstract
Microalgae have adapted to face abiotic stresses by accumulating energy storage molecules such as lipids, which are also of interest to industries. Unfortunately, the impairment in cell division during the accumulation of these molecules constitutes a major bottleneck for the development of efficient microalgae-based biotechnology processes. To address the bottleneck, a multidisciplinary approach was used to study the mechanisms involved in the transition from nitrogen repletion to nitrogen starvation conditions in the marine diatom Phaeodactylum tricornutum that was cultured in a turbidostat. Combining data demonstrate that the different steps of nitrogen deficiency clustered together in a single state in which cells are in equilibrium with their environment. The switch between the nitrogen-replete and the nitrogen-deficient equilibrium is driven by intracellular nitrogen availability. The switch induces a major gene expression change, which is reflected in the reorientation of the carbon metabolism toward an energy storage mode while still operating as a metabolic flywheel. Although the photosynthetic activity is reduced, the chloroplast is kept in a stand-by mode allowing a fast resuming upon nitrogen repletion. Altogether, these results contribute to the understanding of the intricate response of diatoms under stress.
Collapse
Affiliation(s)
- Matteo Scarsini
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Stanislas Thiriet-Rupert
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
- Institut Pasteur, Genetics of Biofilms Laboratory, Paris, France
| | - Brigitte Veidl
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Florence Mondeguer
- Phycotoxins Laboratory, Institut Français de Recherche pour l'Exploitation de la Mer, Nantes, France
| | - Hanhua Hu
- Key Laboratory of Algal Biology, Chinese Academy of Sciences, Wuhan, China
| | - Justine Marchand
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Benoît Schoefs
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| |
Collapse
|
21
|
Santin A, Russo MT, Ferrante MI, Balzano S, Orefice I, Sardo A. Highly Valuable Polyunsaturated Fatty Acids from Microalgae: Strategies to Improve Their Yields and Their Potential Exploitation in Aquaculture. Molecules 2021; 26:7697. [PMID: 34946780 PMCID: PMC8707597 DOI: 10.3390/molecules26247697] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 11/16/2022] Open
Abstract
Microalgae have a great potential for the production of healthy food and feed supplements. Their ability to convert carbon into high-value compounds and to be cultured in large scale without interfering with crop cultivation makes these photosynthetic microorganisms promising for the sustainable production of lipids. In particular, microalgae represent an alternative source of polyunsaturated fatty acids (PUFAs), whose consumption is related to various health benefits for humans and animals. In recent years, several strategies to improve PUFAs' production in microalgae have been investigated. Such strategies include selecting the best performing species and strains and the optimization of culturing conditions, with special emphasis on the different cultivation systems and the effect of different abiotic factors on PUFAs' accumulation in microalgae. Moreover, developments and results obtained through the most modern genetic and metabolic engineering techniques are described, focusing on the strategies that lead to an increased lipid production or an altered PUFAs' profile. Additionally, we provide an overview of biotechnological applications of PUFAs derived from microalgae as safe and sustainable organisms, such as aquafeed and food ingredients, and of the main techniques (and their related issues) for PUFAs' extraction and purification from microalgal biomass.
Collapse
Affiliation(s)
- Anna Santin
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Monia Teresa Russo
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Maria Immacolata Ferrante
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Sergio Balzano
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
- Department of Marine Microbiology and Biogeochemistry, Netherland Institute for Sea Research, Landsdiep 4, 1793 AB Texel, The Netherlands
| | - Ida Orefice
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Angela Sardo
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
- Istituto di Scienze Applicate e Sistemi Intelligenti “Eduardo Caianiello”, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| |
Collapse
|
22
|
Scarsini M, Thurotte A, Veidl B, Amiard F, Niepceron F, Badawi M, Lagarde F, Schoefs B, Marchand J. Metabolite Quantification by Fourier Transform Infrared Spectroscopy in Diatoms: Proof of Concept on Phaeodactylum tricornutum. FRONTIERS IN PLANT SCIENCE 2021; 12:756421. [PMID: 34858459 PMCID: PMC8631545 DOI: 10.3389/fpls.2021.756421] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
Diatoms are feedstock for the production of sustainable biocommodities, including biofuel. The biochemical characterization of newly isolated or genetically modified strains is seminal to identify the strains that display interesting features for both research and industrial applications. Biochemical quantification of organic macromolecules cellular quotas are time-consuming methodologies which often require large amount of biological sample. Vibrational spectroscopy is an essential tool applied in several fields of research. A Fourier transform infrared (FTIR) microscopy-based imaging protocol was developed for the simultaneous cellular quota quantification of lipids, carbohydrates, and proteins of the diatom Phaeodactylum tricornutum. The low amount of sample required for the quantification allows the high throughput quantification on small volume cultures. A proof of concept was performed (1) on nitrogen-starved experimental cultures and (2) on three different P. tricornutum wild-type strains. The results are supported by the observation in situ of lipid droplets by confocal and brightfield microscopy. The results show that major differences exist in the regulation of lipid metabolism between ecotypes of P. tricornutum.
Collapse
Affiliation(s)
- Matteo Scarsini
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
| | - Adrien Thurotte
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
- Institute of Molecular Biosciences, Goethe University Frankfurt, Frankfurt, Germany
| | - Brigitte Veidl
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
| | - Frederic Amiard
- UMR CNRS 6283 Institut des Molécules et des Matériaux du Mans, Le Mans University, Le Mans, France
| | - Frederick Niepceron
- UMR CNRS 6283 Institut des Molécules et des Matériaux du Mans, Le Mans University, Le Mans, France
| | - Myriam Badawi
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
| | - Fabienne Lagarde
- UMR CNRS 6283 Institut des Molécules et des Matériaux du Mans, Le Mans University, Le Mans, France
| | - Benoît Schoefs
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
| | - Justine Marchand
- Mer Molécules Santé, Le Mans University, IUML-FR 3473 CNRS, Le Mans, France
| |
Collapse
|
23
|
Ren J, Yang X, Ma C, Wang Y, Zhao J. Melatonin enhances drought stress tolerance in maize through coordinated regulation of carbon and nitrogen assimilation. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 167:958-969. [PMID: 34571389 DOI: 10.1016/j.plaphy.2021.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 08/15/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
Melatonin is a pleiotropic regulatory molecule in plants and is involved in regulating plant tolerance to drought stress. Here, we conducted transcriptomic and physiological analyses to identify metabolic processes associated with the enhanced tolerance of the melatonin-treated maize (Zea mays L.) seedlings to water deficit. Maize seedlings were foliar sprayed with either 50 μM melatonin or water and exposed to drought stress for 12 d in growth chambers. Drought stress significantly suppressed seedling growth, and melatonin application partially alleviated this growth inhibition. RNA-Seq analysis revealed that genes whose expression was significantly altered by melatonin were mainly related to carbon (C) and nitrogen (N) metabolism. Analysis of transcriptomics, enzyme activity, and metabolite content data, melatonin-treated plants exhibited a higher level of relatively stable C and N metabolism than untreated plants; this phenotype of melatonin-treated plants was associated with their higher photosynthesis, sucrose biosynthesis, N assimilation, and protein biosynthesis capacities under drought stress. Overall, our results suggest that melatonin enhances drought stress tolerance in maize through coordinated regulation of C and N metabolism.
Collapse
Affiliation(s)
- Jianhong Ren
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, 030800, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, 712100, China; College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Xiaoxiao Yang
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, 030800, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi, 712100, China; College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Chunying Ma
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, 030800, China
| | - Yuling Wang
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, 030800, China
| | - Juan Zhao
- College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, 030800, China.
| |
Collapse
|
24
|
Graff van Creveld S, Ben-Dor S, Mizrachi A, Alcolombri U, Hopes A, Mock T, Rosenwasser S, Vardi A. Biochemical Characterization of a Novel Redox-Regulated Metacaspase in a Marine Diatom. Front Microbiol 2021; 12:688199. [PMID: 34566902 PMCID: PMC8455989 DOI: 10.3389/fmicb.2021.688199] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/16/2021] [Indexed: 11/24/2022] Open
Abstract
Programmed cell death (PCD) in marine microalgae was suggested to be one of the mechanisms that facilitates bloom demise, yet its molecular components in phytoplankton are unknown. Phytoplankton are completely lacking any of the canonical components of PCD, such as caspases, but possess metacaspases. Metacaspases were shown to regulate PCD in plants and some protists, but their roles in algae and other organisms are still elusive. Here, we identified and biochemically characterized a type III metacaspase from the model diatom Phaeodactylum tricornutum, termed PtMCA-IIIc. Through expression of recombinant PtMCA-IIIc in E. coli, we revealed that PtMCA-IIIc exhibits a calcium-dependent protease activity, including auto-processing and cleavage after arginine. Similar metacaspase activity was detected in P. tricornutum cell extracts. PtMCA-IIIc overexpressing cells exhibited higher metacaspase activity, while CRISPR/Cas9-mediated knockout cells had decreased metacaspase activity compared to WT cells. Site-directed mutagenesis of cysteines that were predicted to form a disulfide bond decreased recombinant PtMCA-IIIc activity, suggesting its enhancement under oxidizing conditions. One of those cysteines was oxidized, detected in redox proteomics, specifically in response to lethal concentrations of hydrogen peroxide and a diatom derived aldehyde. Phylogenetic analysis revealed that this cysteine-pair is unique and widespread among diatom type III metacaspases. The characterization of a cell death associated protein in diatoms provides insights into the evolutionary origins of PCD and its ecological significance in algal bloom dynamics.
Collapse
Affiliation(s)
- Shiri Graff van Creveld
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
- School of Oceanography, University of Washington, Seattle, WA, United States
| | - Shifra Ben-Dor
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Avia Mizrachi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Uria Alcolombri
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
- Department of Civil, Environmental and Geomatic Engineering, Institute for Environmental Engineering, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Amanda Hopes
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Shilo Rosenwasser
- Robert H. Smith Faculty of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
25
|
Phylogenomic fingerprinting of tempo and functions of horizontal gene transfer within ochrophytes. Proc Natl Acad Sci U S A 2021; 118:2009974118. [PMID: 33419955 DOI: 10.1073/pnas.2009974118] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Horizontal gene transfer (HGT) is an important source of novelty in eukaryotic genomes. This is particularly true for the ochrophytes, a diverse and important group of algae. Previous studies have shown that ochrophytes possess a mosaic of genes derived from bacteria and eukaryotic algae, acquired through chloroplast endosymbiosis and from HGTs, although understanding of the time points and mechanisms underpinning these transfers has been restricted by the depth of taxonomic sampling possible. We harness an expanded set of ochrophyte sequence libraries, alongside automated and manual phylogenetic annotation, in silico modeling, and experimental techniques, to assess the frequency and functions of HGT across this lineage. Through manual annotation of thousands of single-gene trees, we identify continuous bacterial HGT as the predominant source of recently arrived genes in the model diatom Phaeodactylum tricornutum Using a large-scale automated dataset, a multigene ochrophyte reference tree, and mathematical reconciliation of gene trees, we note a probable elevation of bacterial HGTs at foundational points in diatom evolution, following their divergence from other ochrophytes. Finally, we demonstrate that throughout ochrophyte evolutionary history, bacterial HGTs have been enriched in genes encoding secreted proteins. Our study provides insights into the sources and frequency of HGTs, and functional contributions that HGT has made to algal evolution.
Collapse
|
26
|
Santin A, Caputi L, Longo A, Chiurazzi M, Ribera d'Alcalà M, Russo MT, Ferrante MI, Rogato A. Integrative omics identification, evolutionary and structural analysis of low affinity nitrate transporters in diatoms, diNPFs. Open Biol 2021; 11:200395. [PMID: 33823659 PMCID: PMC8025304 DOI: 10.1098/rsob.200395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diatoms are one of the major and most diverse groups of phytoplankton, with chimeric genomes harbouring a combination of genes of bacterial, animal and plant origin. They have developed sophisticated mechanisms to face environmental variations. In marine environments, nutrients concentration shows significant temporal and spatial variability, influencing phytoplankton growth. Among nutrients, nitrogen, present at micromolar levels, is often a limiting resource. Here, we report a comprehensive characterization of the Nitrate Transporter 1/Peptide Transporter Family (NPF) in diatoms, diNPFs. NPFs are well characterized in many organisms where they recognize a broad range of substrates, ranging from short-chained di- and tri-peptides in bacteria, fungi and mammals to a wide variety of molecules including nitrate in higher plants. Scarce information is available for diNPFs. We integrated-omics, phylogenetic, structural and expression analyses, to infer information on their role in diatoms. diNPF genes diverged to produce two distinct clades with strong sequence and structural homology with either bacterial or plant NPFs, with different predicted sub-cellular localization, suggesting that the divergence resulted in functional diversification. Moreover, transcription analysis of diNPF genes under different laboratory and environmental growth conditions suggests that diNPF diversification led to genetic adaptations that might contribute to diatoms ability to flourish in diverse environmental conditions.
Collapse
Affiliation(s)
- Anna Santin
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Luigi Caputi
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Antonella Longo
- BioDiscovery Institute, Denton, TX, USA.,Department of Biological Sciences, University of North Texas, Denton, TX, USA
| | - Maurizio Chiurazzi
- Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, 80131 Naples, Italy
| | | | | | | | - Alessandra Rogato
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy.,Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, 80131 Naples, Italy
| |
Collapse
|
27
|
Helliwell KE, Harrison EL, Christie-Oleza JA, Rees AP, Kleiner FH, Gaikwad T, Downe J, Aguilo-Ferretjans MM, Al-Moosawi L, Brownlee C, Wheeler GL. A Novel Ca 2+ Signaling Pathway Coordinates Environmental Phosphorus Sensing and Nitrogen Metabolism in Marine Diatoms. Curr Biol 2020; 31:978-989.e4. [PMID: 33373640 DOI: 10.1016/j.cub.2020.11.073] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/26/2020] [Accepted: 11/30/2020] [Indexed: 10/22/2022]
Abstract
Diatoms are a diverse and globally important phytoplankton group, responsible for an estimated 20% of carbon fixation on Earth. They frequently form spatially extensive phytoplankton blooms, responding rapidly to increased availability of nutrients, including phosphorus (P) and nitrogen (N). Although it is well established that diatoms are common first responders to nutrient influxes in aquatic ecosystems, little is known of the sensory mechanisms that they employ for nutrient perception. Here, we show that P-limited diatoms use a Ca2+-dependent signaling pathway, not previously described in eukaryotes, to sense and respond to the critical macronutrient P. We demonstrate that P-Ca2+ signaling is conserved between a representative pennate (Phaeodactylum tricornutum) and centric (Thalassiosira pseudonana) diatom. Moreover, this pathway is ecologically relevant, being sensitive to sub-micromolar concentrations of inorganic phosphate and a range of environmentally abundant P forms. Notably, we show that diatom recovery from P limitation requires rapid and substantial increases in N assimilation and demonstrate that this process is dependent on P-Ca2+ signaling. P-Ca2+ signaling thus governs the capacity of diatoms to rapidly sense and respond to P resupply, mediating fundamental cross-talk between the vital nutrients P and N and maximizing diatom resource competition in regions of pulsed nutrient supply.
Collapse
Affiliation(s)
- Katherine E Helliwell
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK.
| | - Ellen L Harrison
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | | | - Andrew P Rees
- Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK
| | - Friedrich H Kleiner
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Trupti Gaikwad
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Joshua Downe
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | | | | | - Colin Brownlee
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Ocean and Earth Science, University of Southampton, Southampton SO14 3ZH, UK
| | - Glen L Wheeler
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| |
Collapse
|
28
|
Leyland B, Zarka A, Didi-Cohen S, Boussiba S, Khozin-Goldberg I. High Resolution Proteome of Lipid Droplets Isolated from the Pennate Diatom Phaeodactylum tricornutum (Bacillariophyceae) Strain pt4 provides mechanistic insights into complex intracellular coordination during nitrogen deprivation. JOURNAL OF PHYCOLOGY 2020; 56:1642-1663. [PMID: 32779202 DOI: 10.1111/jpy.13063] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/14/2020] [Accepted: 07/12/2020] [Indexed: 05/08/2023]
Abstract
Lipid droplets (LDs) are an organelle conserved amongst all eukaryotes, consisting of a neutral lipid core surrounded by a polar lipid monolayer. Many species of microalgae accumulate LDs in response to stress conditions, such as nitrogen starvation. Here, we report the isolation and proteomic profiling of LD proteins from the model oleaginous pennate diatom Phaeodactylum tricornutum, strain Pt4 (UTEX 646). We also provide a quantitative description of LD morphological ontogeny, and fatty acid content. Novel cell disruption and LD isolation methods, combined with suspension-trapping and nanoflow liquid chromatography coupled to high resolution mass spectrometry, yielded an unprecedented number of LD proteins. Predictive annotation of the LD proteome suggests a broad assemblage of proteins with diverse functions, including lipid metabolism and vesicle trafficking, as well as ribosomal and proteasomal machinery. These proteins provide mechanistic insights into LD processes, and evidence for interactions between LDs and other organelles. We identify for the first time several key steps in diatom LD-associated triacylglycerol biosynthesis. Bioinformatic analyses of the LD proteome suggests multiple protein targeting mechanisms, including amphipathic helices, post-translational modifications, and translocation machinery. This work corroborates recent findings from other strains of P. tricornutum, other diatoms, and other eukaryotic organisms, suggesting that the fundamental proteins orchestrating LDs are conserved, and represent an ancient component of the eukaryotic endomembrane system. We postulate a comprehensive model of nitrogen starvation-induced diatom LDs on a molecular scale, and provide a wealth of candidates for metabolic engineering, with the potential to eventually customize LD contents.
Collapse
Affiliation(s)
- Ben Leyland
- The Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Be'er Sheva, 84990, Israel
| | - Aliza Zarka
- The Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Be'er Sheva, 84990, Israel
| | - Shoshana Didi-Cohen
- The Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Be'er Sheva, 84990, Israel
| | - Sammy Boussiba
- The Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Be'er Sheva, 84990, Israel
| | - Inna Khozin-Goldberg
- The Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boker Campus, Be'er Sheva, 84990, Israel
| |
Collapse
|
29
|
Effect of Nitrogen Sources on Omega-3 Polyunsaturated Fatty Acid Biosynthesis and Gene Expression in Thraustochytriidae sp. Mar Drugs 2020; 18:md18120612. [PMID: 33271856 PMCID: PMC7760700 DOI: 10.3390/md18120612] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/26/2020] [Accepted: 11/28/2020] [Indexed: 11/17/2022] Open
Abstract
The molecular mechanism that contributes to nitrogen source dependent omega-3 polyunsaturated fatty acid (n-3 PUFA) synthesis in marine oleaginous protists Thraustochytriidae sp., was explored in this study. The fatty acid (FA) synthesis was significantly influenced by the supplement of various levels of sodium nitrate (SN) (1–50 mM) or urea (1–50 mM). Compared with SN (50 mM) cultivation, cells from urea (50 mM) cultivation accumulated 1.16-fold more n-3 PUFAs (49.49% docosahexaenoic acid (DHA) (w/w, of total FAs) and 5.28% docosapentaenoic acid (DPA) (w/w, of total FAs)). Strikingly higher quantities of short chain FAs (<18 carbons) (52.22-fold of that in urea cultivation) were produced from SN cultivation. Ten candidate reference genes (RGs) were screened by using four statistical methods (geNorm, NormFinder, Bestkeeper and RefFinder). MFT (Mitochondrial folate transporter) and NUC (Nucleolin) were determined as the stable RGs to normalize the RT-qPCR (real-time quantitative polymerase chain reaction) data of essential genes related to n-3 PUFAs-synthesis. Our results elucidated that the gene transcripts of delta(3,5)-delta(2,4)-dienoyl-CoA isomerase, enoyl-CoA hydratase, fatty acid elongase 3, long-chain fatty acid acyl-CoA ligase, and acetyl-CoA carboxylase were up-regulated under urea cultivation, contributing to the extension and unsaturated bond formation. These findings indicated that regulation of the specific genes through nitrogen source could greatly stimulate n-3 PUFA production in Thraustochytriidae sp.
Collapse
|
30
|
The Importance of Protein Phosphorylation for Signaling and Metabolism in Response to Diel Light Cycling and Nutrient Availability in a Marine Diatom. BIOLOGY 2020; 9:biology9070155. [PMID: 32640597 PMCID: PMC7408324 DOI: 10.3390/biology9070155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/01/2020] [Accepted: 07/03/2020] [Indexed: 01/23/2023]
Abstract
Diatoms are major contributors to global primary production and their populations in the modern oceans are affected by availability of iron, nitrogen, phosphate, silica, and other trace metals, vitamins, and infochemicals. However, little is known about the role of phosphorylation in diatoms and its role in regulation and signaling. We report a total of 2759 phosphorylation sites on 1502 proteins detected in Phaeodactylum tricornutum. Conditionally phosphorylated peptides were detected at low iron (n = 108), during the diel cycle (n = 149), and due to nitrogen availability (n = 137). Through a multi-omic comparison of transcript, protein, phosphorylation, and protein homology, we identify numerous proteins and key cellular processes that are likely under control of phospho-regulation. We show that phosphorylation regulates: (1) carbon retrenchment and reallocation during growth under low iron, (2) carbon flux towards lipid biosynthesis after the lights turn on, (3) coordination of transcription and translation over the diel cycle and (4) in response to nitrogen depletion. We also uncover phosphorylation sites for proteins that play major roles in diatom Fe sensing and utilization, including flavodoxin and phytotransferrin (ISIP2A), as well as identify phospho-regulated stress proteins and kinases. These findings provide much needed insight into the roles of protein phosphorylation in diel cycling and nutrient sensing in diatoms.
Collapse
|
31
|
Dell’Aquila G, Zauner S, Heimerl T, Kahnt J, Samel-Gondesen V, Runge S, Hempel F, Maier UG. Mobilization and Cellular Distribution of Phosphate in the Diatom Phaeodactylum tricornutum. FRONTIERS IN PLANT SCIENCE 2020; 11:579. [PMID: 32582227 PMCID: PMC7283521 DOI: 10.3389/fpls.2020.00579] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Unicellular organisms that live in marine environments must cope with considerable fluctuations in the availability of inorganic phosphate (Pi). Here, we investigated the extracellular Pi concentration-dependent expression, as well as the intracellular or extracellular localization, of phosphatases and phosphate transporters of the diatom Phaeodactylum tricornutum. We identified Pi-regulated plasma membrane-localized, ER-localized, and secreted phosphatases, in addition to plasma membrane-localized, vacuolar membrane-localized, and plastid-surrounding membrane-localized phosphate transporters that were also regulated in a Pi concentration-dependent manner. These studies not only add further knowledge to already existing transcriptomic data, but also highlight the capacity of the diatom to distribute Pi intracellularly and to mobilize Pi from extracellular and intracellular resources.
Collapse
Affiliation(s)
| | - Stefan Zauner
- Laboratory for Cell Biology, Philipps University of Marburg, Marburg, Germany
| | | | - Jörg Kahnt
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Vera Samel-Gondesen
- Laboratory for Cell Biology, Philipps University of Marburg, Marburg, Germany
| | - Simon Runge
- Laboratory for Cell Biology, Philipps University of Marburg, Marburg, Germany
| | | | - Uwe G. Maier
- Laboratory for Cell Biology, Philipps University of Marburg, Marburg, Germany
- SYNMIKRO Research Center, Marburg, Germany
| |
Collapse
|
32
|
Nawaly H, Tsuji Y, Matsuda Y. Rapid and precise genome editing in a marine diatom, Thalassiosira pseudonana by Cas9 nickase (D10A). ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
33
|
Transcriptional reprogramming of intermediate metabolism gene induced by Phosphatidylinositol 3-Kinase in Phaeodactylum tricornutum. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101848] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
34
|
Shilova IN, Magasin JD, Mills MM, Robidart JC, Turk-Kubo KA, Zehr JP. Phytoplankton transcriptomic and physiological responses to fixed nitrogen in the California current system. PLoS One 2020; 15:e0231771. [PMID: 32310982 PMCID: PMC7170224 DOI: 10.1371/journal.pone.0231771] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 03/31/2020] [Indexed: 11/18/2022] Open
Abstract
Marine phytoplankton are responsible for approximately half of photosynthesis on Earth. However, their ability to drive ocean productivity depends on critical nutrients, especially bioavailable nitrogen (N) which is scarce over vast areas of the ocean. Phytoplankton differ in their preferences for N substrates as well as uptake efficiencies and minimal N requirements relative to other critical nutrients, including iron (Fe) and phosphorus. In this study, we used the MicroTOOLs high-resolution environmental microarray to examine transcriptomic responses of phytoplankton communities in the California Current System (CCS) transition zone to added urea, ammonium, nitrate, and also Fe in the late summer when N depletion is common. Transcript level changes of photosynthetic, carbon fixation, and nutrient stress genes indicated relief of N limitation in many strains of Prochlorococcus, Synechococcus, and eukaryotic phytoplankton. The transcriptomic responses helped explain shifts in physiological and growth responses observed later. All three phytoplankton groups had increased transcript levels of photosynthesis and/or carbon fixation genes in response to all N substrates. However, only Prochlorococcus had decreased transcript levels of N stress genes and grew substantially, specifically after urea and ammonium additions, suggesting that Prochlorococcus outcompeted other community members in these treatments. Diatom transcript levels of carbon fixation genes increased in response to Fe but not to Fe with N which might have favored phytoplankton that were co-limited by N and Fe. Moreover, transcription patterns of closely related strains indicated variability in N utilization, including nitrate utilization by some high-light adapted Prochlorococcus. Finally, up-regulation of urea transporter genes by both Prochlorococcus and Synechococcus in response to filtered deep water suggested a regulatory mechanism other than classic control via the global N regulator NtcA. This study indicated that co-existing phytoplankton strains experience distinct nutrient stresses in the transition zone of the CCS, an understudied region where oligotrophic and coastal communities naturally mix.
Collapse
Affiliation(s)
- Irina N. Shilova
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail: (INS); (JPZ)
| | - Jonathan D. Magasin
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Matthew M. Mills
- Department of Earth System Science, Stanford University, Stanford, California, United States of America
| | - Julie C. Robidart
- Ocean Technology and Engineering, National Oceanography Centre, Southampton, England, United Kingdom
| | - Kendra A. Turk-Kubo
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Jonathan P. Zehr
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail: (INS); (JPZ)
| |
Collapse
|
35
|
Falciatore A, Jaubert M, Bouly JP, Bailleul B, Mock T. Diatom Molecular Research Comes of Age: Model Species for Studying Phytoplankton Biology and Diversity. THE PLANT CELL 2020; 32:547-572. [PMID: 31852772 PMCID: PMC7054031 DOI: 10.1105/tpc.19.00158] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 10/18/2019] [Accepted: 12/13/2019] [Indexed: 05/08/2023]
Abstract
Diatoms are the world's most diverse group of algae, comprising at least 100,000 species. Contributing ∼20% of annual global carbon fixation, they underpin major aquatic food webs and drive global biogeochemical cycles. Over the past two decades, Thalassiosira pseudonana and Phaeodactylum tricornutum have become the most important model systems for diatom molecular research, ranging from cell biology to ecophysiology, due to their rapid growth rates, small genomes, and the cumulative wealth of associated genetic resources. To explore the evolutionary divergence of diatoms, additional model species are emerging, such as Fragilariopsis cylindrus and Pseudo-nitzschia multistriata Here, we describe how functional genomics and reverse genetics have contributed to our understanding of this important class of microalgae in the context of evolution, cell biology, and metabolic adaptations. Our review will also highlight promising areas of investigation into the diversity of these photosynthetic organisms, including the discovery of new molecular pathways governing the life of secondary plastid-bearing organisms in aquatic environments.
Collapse
Affiliation(s)
- Angela Falciatore
- Institut de Biologie Physico-Chimique, Laboratory of Chloroplast Biology and Light Sensing in Microalgae, UMR7141 Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, 75005 Paris, France
- Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, UMR7238 Sorbonne Université, 75005 Paris, France
| | - Marianne Jaubert
- Institut de Biologie Physico-Chimique, Laboratory of Chloroplast Biology and Light Sensing in Microalgae, UMR7141 Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, 75005 Paris, France
- Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, UMR7238 Sorbonne Université, 75005 Paris, France
| | - Jean-Pierre Bouly
- Institut de Biologie Physico-Chimique, Laboratory of Chloroplast Biology and Light Sensing in Microalgae, UMR7141 Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, 75005 Paris, France
- Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, UMR7238 Sorbonne Université, 75005 Paris, France
| | - Benjamin Bailleul
- Institut de Biologie Physico-Chimique, Laboratory of Chloroplast Biology and Light Sensing in Microalgae, UMR7141 Centre National de la Recherche Scientifique (CNRS), Sorbonne Université, 75005 Paris, France
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| |
Collapse
|
36
|
Leyland B, Boussiba S, Khozin-Goldberg I. A Review of Diatom Lipid Droplets. BIOLOGY 2020; 9:biology9020038. [PMID: 32098118 PMCID: PMC7168155 DOI: 10.3390/biology9020038] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/20/2022]
Abstract
The dynamic nutrient availability and photon flux density of diatom habitats necessitate buffering capabilities in order to maintain metabolic homeostasis. This is accomplished by the biosynthesis and turnover of storage lipids, which are sequestered in lipid droplets (LDs). LDs are an organelle conserved among eukaryotes, composed of a neutral lipid core surrounded by a polar lipid monolayer. LDs shield the intracellular environment from the accumulation of hydrophobic compounds and function as a carbon and electron sink. These functions are implemented by interconnections with other intracellular systems, including photosynthesis and autophagy. Since diatom lipid production may be a promising objective for biotechnological exploitation, a deeper understanding of LDs may offer targets for metabolic engineering. In this review, we provide an overview of diatom LD biology and biotechnological potential.
Collapse
|
37
|
Marter P, Schmidt S, Kiontke S, Moog D. Optimized mRuby3 is a Suitable Fluorescent Protein for in vivo Co-localization Studies with GFP in the Diatom Phaeodactylum tricornutum. Protist 2020; 171:125715. [PMID: 32062589 DOI: 10.1016/j.protis.2020.125715] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 12/19/2019] [Accepted: 12/27/2019] [Indexed: 11/19/2022]
Abstract
Phaeodactylum tricornutum is an ecologically and evolutionarily relevant microalga that has developed into an important model for molecular biological studies on organisms with complex plastids. The diatom is particularly suitable for in vivo protein localization analyses via fluorescence microscopy in which the green fluorescent protein (GFP) and its derivatives are dominantly used. Whereas GFP fluorescence emission is usually measured between 500 and 520nm in confocal microscopy, the autofluorescence of the P. tricornutum plastid is detected above 625nm. Here we established the fluorescent protein mRuby3 as tag for efficient in vivo protein localization studies by expressing a codon-optimized gene in P. tricornutum. mRuby3 was directed to seven different subcellular localizations by means of full-length marker protein or N-/C-terminal targeting signal fusions; its emission was detected efficiently between 580 and 605nm, being unequivocally distinguishable from the plastid autofluorescence in vivo. Moreover, mRuby3 proved to be highly suitable for co-localization experiments using confocal laser scanning microscopy in which mRuby3 fusion proteins were expressed in parallel with GFP-tagged proteins. Our results show the potential of mRuby3 for its application in studying protein targeting and localization in P. tricornutum, particularly underlining its compatibility with GFP and the plastid autofluorescence in signal detection.
Collapse
Affiliation(s)
- Pia Marter
- Laboratory for Cell Biology, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany
| | - Sebastian Schmidt
- Laboratory for Cell Biology, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany
| | - Stephan Kiontke
- Molecular Plant Physiology and Photobiology, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany
| | - Daniel Moog
- Laboratory for Cell Biology, Philipps University Marburg, Karl-von-Frisch-Str. 8, 35032 Marburg, Germany; SYNMIKRO Research Center, Hans-Meerwein-Str. 6, 35032 Marburg, Germany.
| |
Collapse
|
38
|
Moosburner MA, Gholami P, McCarthy JK, Tan M, Bielinski VA, Allen AE. Multiplexed Knockouts in the Model Diatom Phaeodactylum by Episomal Delivery of a Selectable Cas9. Front Microbiol 2020; 11:5. [PMID: 32047486 PMCID: PMC6997545 DOI: 10.3389/fmicb.2020.00005] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 01/03/2020] [Indexed: 11/13/2022] Open
Abstract
Marine diatoms are eukaryotic microalgae that play significant ecological and biogeochemical roles in oceans. They also have significant potential as organismal platforms for exploitation to address biotechnological and industrial goals. In order to address both modes of research, sophisticated molecular and genetic tools are required. We presented here new and improved methodologies for introducing CRISPR-Cas9 to the model diatom Phaeodactylum tricornutum cells and a streamlined protocol for genotyping mutant cell lines with previously unknown phenotypes. First, bacterial-conjugation was optimized for the delivery of Cas9 by transcriptionally fusing Cas9 to a selectable marker by the 2A peptide. An episome cloning strategy using both negative and positive selection was developed to streamline CRISPR-episome assembly. Next, cell line picking and genotyping strategies, that utilize manual sequencing curation, TIDE sequencing analysis, and a T7 endonuclease assay, were developed to shorten the time required to generate mutants. Following this new experimental pipeline, both single-gene and two-gene knockout cell lines were generated at mutagenesis efficiencies of 48% and 25%, respectively. Lastly, a protocol for precise gene insertions via CRISPR-Cas9 targeting was developed using particle-bombardment transformation methods. Overall, the novel Cas9 episome design and improved genotyping methods presented here allow for quick and easy genotyping and isolation of Phaeodactylum mutant cell lines (less than 3 weeks) without relying on a known phenotype to screen for mutants.
Collapse
Affiliation(s)
- Mark Andrew Moosburner
- Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States.,J. Craig Venter Institute, La Jolla, CA, United States
| | | | | | - Maxine Tan
- Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States.,J. Craig Venter Institute, La Jolla, CA, United States
| | | | - Andrew E Allen
- Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, United States.,J. Craig Venter Institute, La Jolla, CA, United States
| |
Collapse
|
39
|
Ait-Mohamed O, Novák Vanclová AMG, Joli N, Liang Y, Zhao X, Genovesio A, Tirichine L, Bowler C, Dorrell RG. PhaeoNet: A Holistic RNAseq-Based Portrait of Transcriptional Coordination in the Model Diatom Phaeodactylum tricornutum. FRONTIERS IN PLANT SCIENCE 2020; 11:590949. [PMID: 33178253 PMCID: PMC7596299 DOI: 10.3389/fpls.2020.590949] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/15/2020] [Indexed: 05/04/2023]
Abstract
Transcriptional coordination is a fundamental component of prokaryotic and eukaryotic cell biology, underpinning the cell cycle, physiological transitions, and facilitating holistic responses to environmental stress, but its overall dynamics in eukaryotic algae remain poorly understood. Better understanding of transcriptional partitioning may provide key insights into the primary metabolism pathways of eukaryotic algae, which frequently depend on intricate metabolic associations between the chloroplasts and mitochondria that are not found in plants. Here, we exploit 187 publically available RNAseq datasets generated under varying nitrogen, iron and phosphate growth conditions to understand the co-regulatory principles underpinning transcription in the model diatom Phaeodactylum tricornutum. Using WGCNA (Weighted Gene Correlation Network Analysis), we identify 28 merged modules of co-expressed genes in the P. tricornutum genome, which show high connectivity and correlate well with previous microarray-based surveys of gene co-regulation in this species. We use combined functional, subcellular localization and evolutionary annotations to reveal the fundamental principles underpinning the transcriptional co-regulation of genes implicated in P. tricornutum chloroplast and mitochondrial metabolism, as well as the functions of diverse transcription factors underpinning this co-regulation. The resource is publically available as PhaeoNet, an advanced tool to understand diatom gene co-regulation.
Collapse
Affiliation(s)
- Ouardia Ait-Mohamed
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
| | - Anna M. G. Novák Vanclová
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
| | - Nathalie Joli
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
| | - Yue Liang
- Department of Oceanography, Dalhousie University, Halifax, NS, Canada
| | - Xue Zhao
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
- Université de Nantes, CNRS, UFIP, UMR 6286, Nantes, France
| | - Auguste Genovesio
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
| | - Leila Tirichine
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
- Université de Nantes, CNRS, UFIP, UMR 6286, Nantes, France
- *Correspondence: Leila Tirichine,
| | - Chris Bowler
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
- Chris Bowler,
| | - Richard G. Dorrell
- Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
| |
Collapse
|
40
|
RSH enzyme diversity for (p)ppGpp metabolism in Phaeodactylum tricornutum and other diatoms. Sci Rep 2019; 9:17682. [PMID: 31776430 PMCID: PMC6881373 DOI: 10.1038/s41598-019-54207-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 11/05/2019] [Indexed: 12/28/2022] Open
Abstract
The nucleotides guanosine tetraphosphate and pentaphosphate (together known as (p)ppGpp or magic spot) are produced in plant plastids from GDP/GTP and ATP by RelA-SpoT homologue (RSH) enzymes. In the model plant Arabidopsis (p)ppGpp regulates chloroplast transcription and translation to affect growth, and is also implicated in acclimation to stress. However, little is known about (p)ppGpp metabolism or its evolution in other photosynthetic eukaryotes. Here we studied (p)ppGpp metabolism in the marine diatom Phaeodactylum tricornutum. We identified three expressed RSH genes in the P. tricornutum genome, and determined the enzymatic activity of the corresponding enzymes by heterologous expression in bacteria. We showed that two P. tricornutum RSH are (p)ppGpp synthetases, despite substitution of a residue within the active site believed critical for activity, and that the third RSH is a bifunctional (p)ppGpp synthetase and hydrolase, the first of its kind demonstrated in a photosynthetic eukaryote. A broad phylogenetic analysis then showed that diatom RSH belong to novel algal RSH clades. Together our work significantly expands the horizons of (p)ppGpp signalling in the photosynthetic eukaryotes by demonstrating an unexpected functional, structural and evolutionary diversity in RSH enzymes from organisms with plastids derived from red algae.
Collapse
|
41
|
Smith SR, Dupont CL, McCarthy JK, Broddrick JT, Oborník M, Horák A, Füssy Z, Cihlář J, Kleessen S, Zheng H, McCrow JP, Hixson KK, Araújo WL, Nunes-Nesi A, Fernie A, Nikoloski Z, Palsson BO, Allen AE. Evolution and regulation of nitrogen flux through compartmentalized metabolic networks in a marine diatom. Nat Commun 2019; 10:4552. [PMID: 31591397 PMCID: PMC6779911 DOI: 10.1038/s41467-019-12407-y] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 09/03/2019] [Indexed: 01/15/2023] Open
Abstract
Diatoms outcompete other phytoplankton for nitrate, yet little is known about the mechanisms underpinning this ability. Genomes and genome-enabled studies have shown that diatoms possess unique features of nitrogen metabolism however, the implications for nutrient utilization and growth are poorly understood. Using a combination of transcriptomics, proteomics, metabolomics, fluxomics, and flux balance analysis to examine short-term shifts in nitrogen utilization in the model pennate diatom in Phaeodactylum tricornutum, we obtained a systems-level understanding of assimilation and intracellular distribution of nitrogen. Chloroplasts and mitochondria are energetically integrated at the critical intersection of carbon and nitrogen metabolism in diatoms. Pathways involved in this integration are organelle-localized GS-GOGAT cycles, aspartate and alanine systems for amino moiety exchange, and a split-organelle arginine biosynthesis pathway that clarifies the role of the diatom urea cycle. This unique configuration allows diatoms to efficiently adjust to changing nitrogen status, conferring an ecological advantage over other phytoplankton taxa.
Collapse
Affiliation(s)
- Sarah R Smith
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - Chris L Dupont
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - James K McCarthy
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - Jared T Broddrick
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Miroslav Oborník
- Institute of Parasitology, Biology Centre Czech Academy of Sciences, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Aleš Horák
- Institute of Parasitology, Biology Centre Czech Academy of Sciences, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Zoltán Füssy
- Institute of Parasitology, Biology Centre Czech Academy of Sciences, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Jaromír Cihlář
- Institute of Parasitology, Biology Centre Czech Academy of Sciences, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 31, 370 05, České Budějovice, Czech Republic
| | - Sabrina Kleessen
- Targenomix, GmbH, Wissenschaftspark Potsdam-Golm, 14476, Potsdam, Germany
| | - Hong Zheng
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - John P McCrow
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA
| | - Kim K Hixson
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max-Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Adriano Nunes-Nesi
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Alisdair Fernie
- Max Planck Institut of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Zoran Nikoloski
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Bernhard O Palsson
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Andrew E Allen
- Microbial and Environmental Genomics, J. Craig Venter Institute, La Jolla, CA, 92037, USA.
- Scripps Institution of Oceanography, Integrative Oceanography Division, University of California, San Diego, La Jolla, CA, 92093, USA.
| |
Collapse
|
42
|
Strategies among phytoplankton in response to alleviation of nutrient stress in a subtropical gyre. ISME JOURNAL 2019; 13:2984-2997. [PMID: 31439897 DOI: 10.1038/s41396-019-0489-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 07/07/2019] [Accepted: 08/02/2019] [Indexed: 11/08/2022]
Abstract
Despite generally low primary productivity and diatom abundances in oligotrophic subtropical gyres, the North Atlantic Subtropical Gyre (NASG) exhibits significant diatom-driven carbon export on an annual basis. Subsurface pulses of nutrients likely fuel brief episodes of diatom growth, but the exact mechanisms utilized by diatoms in response to these nutrient injections remain understudied within near-natural settings. Here we simulated delivery of subsurface nutrients and compare the response among eukaryotic phytoplankton using a combination of physiological techniques and metatranscriptomics. We show that eukaryotic phytoplankton groups exhibit differing levels of transcriptional responsiveness and expression of orthologous genes in response to release from nutrient limitation. In particular, strategies for use of newly delivered nutrients are distinct among phytoplankton groups. Diatoms channel new nitrate to growth-related strategies while physiological measurements and gene expression patterns of other groups suggest alternative strategies. The gene expression patterns displayed here provide insights into the cellular mechanisms that underlie diatom subsistence during chronic nitrogen-depleted conditions and growth upon nutrient delivery that can enhance carbon export from the surface ocean.
Collapse
|
43
|
Metabolic Innovations Underpinning the Origin and Diversification of the Diatom Chloroplast. Biomolecules 2019; 9:biom9080322. [PMID: 31366180 PMCID: PMC6723447 DOI: 10.3390/biom9080322] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 12/13/2022] Open
Abstract
Of all the eukaryotic algal groups, diatoms make the most substantial contributions to photosynthesis in the contemporary ocean. Understanding the biological innovations that have occurred in the diatom chloroplast may provide us with explanations to the ecological success of this lineage and clues as to how best to exploit the biology of these organisms for biotechnology. In this paper, we use multi-species transcriptome datasets to compare chloroplast metabolism pathways in diatoms to other algal lineages. We identify possible diatom-specific innovations in chloroplast metabolism, including the completion of tocopherol synthesis via a chloroplast-targeted tocopherol cyclase, a complete chloroplast ornithine cycle, and chloroplast-targeted proteins involved in iron acquisition and CO2 concentration not shared between diatoms and their closest relatives in the stramenopiles. We additionally present a detailed investigation of the chloroplast metabolism of the oil-producing diatom Fistulifera solaris, which is of industrial interest for biofuel production. These include modified amino acid and pyruvate hub metabolism that might enhance acetyl-coA production for chloroplast lipid biosynthesis and the presence of a chloroplast-localised squalene synthesis pathway unknown in other diatoms. Our data provides valuable insights into the biological adaptations underpinning an ecologically critical lineage, and how chloroplast metabolism can change even at a species level in extant algae.
Collapse
|
44
|
Busseni G, Vieira FRJ, Amato A, Pelletier E, Pierella Karlusich JJ, Ferrante MI, Wincker P, Rogato A, Bowler C, Sanges R, Maiorano L, Chiurazzi M, d'Alcalà MR, Caputi L, Iudicone D. Meta-omics reveals genetic flexibility of diatom nitrogen transporters in response to environmental changes. Mol Biol Evol 2019; 36:2522-2535. [PMID: 31259367 PMCID: PMC6805229 DOI: 10.1093/molbev/msz157] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/05/2019] [Accepted: 06/22/2019] [Indexed: 01/27/2023] Open
Abstract
Diatoms (Bacillariophyta), one of the most abundant and diverse groups of marine phytoplankton, respond rapidly to the supply of new nutrients, often out-competing other phytoplankton. Herein, we integrated analyses of the evolution, distribution and expression modulation of two gene families involved in diatom nitrogen uptake (DiAMT1 and DiNRT2), in order to infer the main drivers of divergence in a key functional trait of phytoplankton. Our results suggest that major steps in the evolution of the two gene families reflected key events triggering diatom radiation and diversification. Their expression is modulated in the contemporary ocean by seawater temperature, nitrate and iron concentrations. Moreover, the differences in diversity and expression of these gene families throughout the water column hint at a possible link with bacterial activity. This study represents a proof-of-concept of how a holistic approach may shed light on the functional biology of organisms in their natural environment.
Collapse
Affiliation(s)
- Greta Busseni
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy
| | - Fabio Rocha Jimenez Vieira
- Institut de biologie de l'Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Université Paris, Paris, France
| | - Alberto Amato
- Laboratoire de Physiologie Cellulaire et Végétale, Univ. Grenoble Alpes, CEA, INRA, CNRS. BIG, 17 rue des Martyrs Grenoble cedex 9, France
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France.,FR2022/Tara Oceans-GOSEE, 3 rue Michel-Ange, Paris, France
| | - Juan J Pierella Karlusich
- Institut de biologie de l'Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Université Paris, Paris, France
| | | | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, Evry, France.,FR2022/Tara Oceans-GOSEE, 3 rue Michel-Ange, Paris, France
| | - Alessandra Rogato
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.,Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, Naples, Italy
| | - Chris Bowler
- Institut de biologie de l'Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Université Paris, Paris, France
| | - Remo Sanges
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.,Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea 265, Trieste, Italy
| | - Luigi Maiorano
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.,Dipartimento di Biologia e Biotecnologie "Charles Darwin", Università di Roma "La Sapienza", Viale dell'Università 32, Roma, Italy
| | - Maurizio Chiurazzi
- Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, Naples, Italy
| | | | - Luigi Caputi
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy
| | | |
Collapse
|
45
|
Ren X, Deschênes JS, Tremblay R, Peres S, Jolicoeur M. A kinetic metabolic study of lipid production in Chlorella protothecoides under heterotrophic condition. Microb Cell Fact 2019; 18:113. [PMID: 31253148 PMCID: PMC6598345 DOI: 10.1186/s12934-019-1163-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/19/2019] [Indexed: 11/13/2022] Open
Abstract
Background Microalgae have been proposed as potential platform to produce lipid-derived products, such as biofuels. Knowledge on the intracellular carbon flow distribution may identify key metabolic processes during lipid synthesis thus refining culture/genetic strategies to maximize cell lipid productivity. A kinetic metabolic model simulating cell metabolic behavior and lipid production was first applied in the microalgae platform Chlorella protothecoides under heterotrophic condition. It combines both physiology and flux information in a kinetic approach. Cell nutrition, growth, lipid production and almost 30 metabolic intermediates covering central carbon metabolism were included and simulated. Results Model simulations were shown to adequately agree with experimental data, which is suggesting that the proposed model copes with Chlorella protothecoides cells’ biology. The dynamic metabolic flux analysis using the model showed a reversible starch flux from accumulation to decomposing when glucose reached depletion, while net lipid flux shows a quasi-constant rate. The sensitive flux parameters on starch and lipid metabolism suggested that starch synthesis is the major competing pathway that affects lipid accumulation in C. protothecoides. Flux analysis also demonstrated that high lipid yield under heterotrophic condition is accompanied with high lipid flux and low TCA activity. Meanwhile, the dynamic flux distribution also suggests a relatively constant ratio of glucose distributed to biomass, lipid, starch, nucleotides as well as pentose phosphate pathway. Conclusion The model described not only experimental data, but also unraveled intracellular carbon flow distribution and identify key metabolic processes during lipid synthesis. Most of the metabolic kinetics also showed statistical significance for metabolic mechanism. Therefore, this study unravels the mechanisms of the glucose impact on the dynamic carbon flux distribution, thus improving our understanding of the links between carbon fluxes and lipid metabolism in C. protothecoides. Electronic supplementary material The online version of this article (10.1186/s12934-019-1163-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Xiaojie Ren
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo, China.,Research Laboratory in Applied Metabolic Engineering, Department of Chemical Engineering, École Polytechnique de Montreal, Centre-ville Station, P.O. Box 6079, Montreal, H3C 3A7, QC, Canada
| | | | - Réjean Tremblay
- Université du Québec à Rimouski, 310 allée des Ursulines, Rimouski, QC, G5L 3A1, Canada
| | - Sabine Peres
- LRI, Université Paris-Sud, CNRS, Université Paris-Saclay, 91405, Orsay, France.,MaIAGE, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Mario Jolicoeur
- Research Laboratory in Applied Metabolic Engineering, Department of Chemical Engineering, École Polytechnique de Montreal, Centre-ville Station, P.O. Box 6079, Montreal, H3C 3A7, QC, Canada.
| |
Collapse
|
46
|
Nitrate and ammonium fluxes to diatoms and dinoflagellates at a single cell level in mixed field communities in the sea. Sci Rep 2019; 9:1424. [PMID: 30723237 PMCID: PMC6363804 DOI: 10.1038/s41598-018-38059-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/19/2018] [Indexed: 01/11/2023] Open
Abstract
Growth of large phytoplankton is considered to be diffusion limited at low nutrient concentrations, yet their constraints and contributions to carbon (C) and nitrogen fluxes in field plankton communities are poorly quantified under this condition. Using secondary ion mass spectrometry (SIMS), we quantified cell-specific assimilation rates of C, nitrate, and ammonium in summer communities of large phytoplankton when dissolved inorganic nitrogen concentrations are low in temperate coastal regions. Chain-forming diatoms composed 6% of total particulate organic carbon, but contributed 20% of C assimilation, 54% of nitrate assimilation and 32% of ammonium assimilation within the plankton community. In contrast, large dinoflagellates composed 11% of total POC, and contributed 14% of the C assimilation, 4% of ammonium and 9% of nitrate assimilation within the plankton community. Measured cell-specific C and nitrate assimilation rate match the Redfield ratio and the maximal nitrate assimilation in Chaetoceros spp. predicted by mass transfer theory. However, average ammonium assimilation rates were 30 and 340% higher than predicted by mass transfer theory in Tripos/Ceratium and Chaetoceros, respectively, suggesting that microbial interactions in the phycosphere may facilitate substantial luxury ammonium uptake by Chaetoceros in environments with fluctuating nitrate concentrations.
Collapse
|
47
|
Olofsson M, Kourtchenko O, Zetsche E, Marchant HK, Whitehouse MJ, Godhe A, Ploug H. High single-cell diversity in carbon and nitrogen assimilations by a chain-forming diatom across a century. Environ Microbiol 2019; 21:142-151. [PMID: 30277299 PMCID: PMC7379523 DOI: 10.1111/1462-2920.14434] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 09/26/2018] [Indexed: 11/30/2022]
Abstract
Almost a century ago Redfield discovered a relatively constant ratio between carbon, nitrogen and phosphorus in particulate organic matter and nitrogen and phosphorus of dissolved nutrients in seawater. Since then, the riverine export of nitrogen to the ocean has increased 20 fold. High abundance of resting stages in sediment layers dated more than a century back indicate that the common planktonic diatom Skeletonema marinoi has endured this eutrophication. We germinated unique genotypes from resting stages originating from isotope-dated sediment layers (15 and 80 years old) in a eutrophied fjord. Using secondary ion mass spectrometry (SIMS) combined with stable isotopic tracers, we show that the cell-specific carbon and nitrogen assimilation rates vary by an order of magnitude on a single-cell level but are significantly correlated during the exponential growth phase, resulting in constant assimilation quota in cells with identical genotypes. The assimilation quota varies largely between different clones independent of age. We hypothesize that the success of S. marinoi in coastal waters may be explained by its high diversity of nutrient demand not only at a clone-specific level but also at the single-cell level, whereby the population can sustain and adapt to dynamic nutrient conditions in the environment.
Collapse
Affiliation(s)
- Malin Olofsson
- Department of Marine SciencesUniversity of GothenburgBox 461, 405 30GothenburgSweden
| | - Olga Kourtchenko
- Department of Marine SciencesUniversity of GothenburgBox 461, 405 30GothenburgSweden
| | - Eva‐Maria Zetsche
- Department of Marine SciencesUniversity of GothenburgBox 461, 405 30GothenburgSweden
| | - Hannah K. Marchant
- Max Planck Institute for Marine MicrobiologyCelsiusstrasse 1, 28359BremenGermany
| | | | - Anna Godhe
- Department of Marine SciencesUniversity of GothenburgBox 461, 405 30GothenburgSweden
| | - Helle Ploug
- Department of Marine SciencesUniversity of GothenburgBox 461, 405 30GothenburgSweden
| |
Collapse
|
48
|
Liang MH, Wang L, Wang Q, Zhu J, Jiang JG. High-value bioproducts from microalgae: Strategies and progress. Crit Rev Food Sci Nutr 2018; 59:2423-2441. [PMID: 29676930 DOI: 10.1080/10408398.2018.1455030] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Microalgae have been considered as alternative sustainable resources for high-value bioproducts such as lipids (especially triacylglycerides [TAGs]), polyunsaturated fatty acids (PUFAs), and carotenoids, due to their relatively high photosynthetic efficiency, no arable land requirement, and ease of scale-up. It is of great significance to exploit microalgae for the production of high-value bioproducts. How to improve the content or productivity of specific bioproducts has become one of the most urgent challenges. In this review, we will describe high-value bioproducts from microalgae and their biosynthetic pathways (mainly for lipids, PUFAs, and carotenoids). Recent progress and strategies for the enhanced production of bioproducts from microalgae are also described in detail, and these strategies take advantages of optimized cultivation conditions with abiotic stress, chemical stress (addition of metabolic precursors, phytohormones, chemical inhibitors, and chemicals inducing oxidative stress response), and molecular approaches such as metabolic engineering, transcriptional engineering, and gene disruption strategies (mainly RNAi, antisense RNA, miRNA-based knockdown, and CRISPR/Cas9).
Collapse
Affiliation(s)
- Ming-Hua Liang
- a College of Food Science and Engineering, South China University of Technology , Guangzhou , China
| | - Ling Wang
- b School of Biotechnology, Jiangsu University of Science and Technology , Zhenjiang , China
| | - Qiming Wang
- c College of Bioscience and Biotechnology, Hunan Agricultural University , Changsha , China
| | - Jianhua Zhu
- b School of Biotechnology, Jiangsu University of Science and Technology , Zhenjiang , China.,c College of Bioscience and Biotechnology, Hunan Agricultural University , Changsha , China.,d Department of Plant Science and Landscape Architecture, University of Maryland , College Park , Maryland , USA
| | - Jian-Guo Jiang
- a College of Food Science and Engineering, South China University of Technology , Guangzhou , China
| |
Collapse
|
49
|
Lupette J, Jaussaud A, Vigor C, Oger C, Galano JM, Réversat G, Vercauteren J, Jouhet J, Durand T, Maréchal E. Non-Enzymatic Synthesis of Bioactive Isoprostanoids in the Diatom Phaeodactylum following Oxidative Stress. PLANT PHYSIOLOGY 2018; 178:1344-1357. [PMID: 30237205 PMCID: PMC6236624 DOI: 10.1104/pp.18.00925] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/11/2018] [Indexed: 05/08/2023]
Abstract
The ecological success of diatoms requires a remarkable ability to survive many types of stress, including variations in temperature, light, salinity, and nutrient availability. On exposure to these stresses, diatoms exhibit common responses, including growth arrest, impairment of photosynthesis, production of reactive oxygen species, and accumulation of triacylglycerol (TAG). We studied the production of cyclopentane oxylipins derived from fatty acids in the diatom Phaeodactylum tricornutum in response to oxidative stress. P. tricornutum lacks the enzymatic pathway for producing cyclopentane-oxylipins, such as jasmonate, prostaglandins, or thromboxanes. In cells subjected to increasing doses of hydrogen peroxide (H2O2), we detected nonenzymatic production of isoprostanoids, including six phytoprostanes, three F2t-isoprostanes, two F3t-isoprostanes, and three F4t-neuroprostanes, by radical peroxidation of α-linolenic, arachidonic, eicosapentaenoic, and docosahexanoic acids, respectively. H2O2 also triggered photosynthesis impairment and TAG accumulation. F1t-phytoprostanes constitute the major class detected (300 pmol per 1 million cells; intracellular concentration, ∼4 µm). Only two glycerolipids, phosphatidylcholine and diacylglycerylhydroxymethyl-trimethyl-alanine, could provide all substrates for these isoprostanoids. Treatment of P. tricornutum with nine synthetic isoprostanoids produced an effect in the micromolar range, marked by the accumulation of TAG and reduced growth, without affecting photosynthesis. Therefore, the emission of H2O2 and free radicals upon exposure to stresses can lead to glycerolipid peroxidation and nonenzymatic synthesis of isoprostanoids, inhibiting growth and contributing to the induction of TAG accumulation via unknown processes. This characterization of nonenzymatic oxylipins in P. tricornutum opens a field of research on the study of processes controlled by isoprostanoid signaling in various physiological and environmental contexts in diatoms.
Collapse
Affiliation(s)
- Josselin Lupette
- Laboratoire de Physiologie Cellulaire et Végétale, Unité Mixte de Recherche 5168, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique, Institut National de la Recherche Agronomique, Université Grenoble Alpes, Institut de Biosciences Biotechnologies de Grenoble, Commissariat à l'Energie Atomique Grenoble, 38000 Grenoble, France
| | - Antoine Jaussaud
- Laboratoire de Physiologie Cellulaire et Végétale, Unité Mixte de Recherche 5168, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique, Institut National de la Recherche Agronomique, Université Grenoble Alpes, Institut de Biosciences Biotechnologies de Grenoble, Commissariat à l'Energie Atomique Grenoble, 38000 Grenoble, France
| | - Claire Vigor
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Guillaume Réversat
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Joseph Vercauteren
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Juliette Jouhet
- Laboratoire de Physiologie Cellulaire et Végétale, Unité Mixte de Recherche 5168, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique, Institut National de la Recherche Agronomique, Université Grenoble Alpes, Institut de Biosciences Biotechnologies de Grenoble, Commissariat à l'Energie Atomique Grenoble, 38000 Grenoble, France
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, Unité Mixte de Recherche 5247, Université de Montpellier, Centre National de la Recherche Scientifique, Ecole Nationale Supérieure de Chimie de Montpellier, F-34093 Montpellier cedex 05, France
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire et Végétale, Unité Mixte de Recherche 5168, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique, Institut National de la Recherche Agronomique, Université Grenoble Alpes, Institut de Biosciences Biotechnologies de Grenoble, Commissariat à l'Energie Atomique Grenoble, 38000 Grenoble, France
| |
Collapse
|
50
|
Kroth PG, Bones AM, Daboussi F, Ferrante MI, Jaubert M, Kolot M, Nymark M, Río Bártulos C, Ritter A, Russo MT, Serif M, Winge P, Falciatore A. Genome editing in diatoms: achievements and goals. PLANT CELL REPORTS 2018; 37:1401-1408. [PMID: 30167805 DOI: 10.1007/s00299-018-2334-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/07/2018] [Indexed: 05/20/2023]
Abstract
Diatoms are major components of phytoplankton and play a key role in the ecology of aquatic ecosystems. These algae are of great scientific importance for a wide variety of research areas, ranging from marine ecology and oceanography to biotechnology. During the last 20 years, the availability of genomic information on selected diatom species and a substantial progress in genetic manipulation, strongly contributed to establishing diatoms as molecular model organisms for marine biology research. Recently, tailored TALEN endonucleases and the CRISPR/Cas9 system were utilized in diatoms, allowing targeted genetic modifications and the generation of knockout strains. These approaches are extremely valuable for diatom research because breeding, forward genetic screens by random insertion, and chemical mutagenesis are not applicable to the available model species Phaeodactylum tricornutum and Thalassiosira pseudonana, which do not cross sexually in the lab. Here, we provide an overview of the genetic toolbox that is currently available for performing stable genetic modifications in diatoms. We also discuss novel challenges that need to be addressed to fully exploit the potential of these technologies for the characterization of diatom biology and for metabolic engineering.
Collapse
Affiliation(s)
- Peter G Kroth
- Fachbereich Biologie, Universität Konstanz, 78457, Konstanz, Germany.
| | - Atle M Bones
- Cell, Molecular Biology and Genomics Group, Department of Biology, Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | - Fayza Daboussi
- LISBP, Université de Toulouse, CNRS, INSA, 135 Avenue de Rangueil, 31077, Toulouse, France
| | - Maria I Ferrante
- Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale 1, Naples, 80121, Italy
| | - Marianne Jaubert
- Laboratoire de Biologie Computationnelle et Quantitative, Institut de Biologie Paris-Seine, Sorbonne Université, CNRS, 75005, Paris, France
| | - Misha Kolot
- Institute of Plant Sciences and Genetics in Agriculture, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, 76100, Rehovot, Israel
- Department of Biochemistry and Molecular Biology, Tel-Aviv University, Tel-Aviv, 69978, Israel
| | - Marianne Nymark
- Cell, Molecular Biology and Genomics Group, Department of Biology, Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | | | - Andrés Ritter
- Laboratoire de Biologie Computationnelle et Quantitative, Institut de Biologie Paris-Seine, Sorbonne Université, CNRS, 75005, Paris, France
| | - Monia T Russo
- Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale 1, Naples, 80121, Italy
| | - Manuel Serif
- LISBP, Université de Toulouse, CNRS, INSA, 135 Avenue de Rangueil, 31077, Toulouse, France
| | - Per Winge
- Cell, Molecular Biology and Genomics Group, Department of Biology, Norwegian University of Science and Technology, 7491, Trondheim, Norway
| | - Angela Falciatore
- Laboratoire de Biologie Computationnelle et Quantitative, Institut de Biologie Paris-Seine, Sorbonne Université, CNRS, 75005, Paris, France.
| |
Collapse
|