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Ortiz Tena F, Bickel V, Steinweg C, Posten C. Continuous microalgae cultivation for wastewater treatment - Development of a process strategy during day and night. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169082. [PMID: 38056654 DOI: 10.1016/j.scitotenv.2023.169082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 12/08/2023]
Abstract
Conventional wastewater treatment (WWT) is not able to recycle nutrients from the wastewater (WW) directly. Microalgae integrate the valuable nutrients nitrogen and phosphorus within their biomass very efficiently, making them predestined for an application in WWT. Nevertheless, microalgae-based processes are driven by natural sunlight as energy source, making a continuous process mode during day and night difficult. The aim of this study was therefore to investigate metabolic activities of the continuously cultivated microalgae Chlorella vulgaris at light and dark periods (16 h,8 h) with focus on nutrient uptake during night from a synthetic WW. Varying the dilution rate D (D = 0.0-1.0 d-1 in 0.1 d-1-steps) causes different limitations for algae growth. Nutrient limitations at low D's cause maximum accumulation of intracellular storage components (sum of carbohydrates and lipids) of ~70 % of dry biomass, starch is converted to lipids at the absence of light. From middle to high D's, the growth rate is determined by light limitation, reducing the intracellular storage components to ~20 % of dry biomass. Complete nutrient uptake is measurable up to D = 0.5 d-1, marking the maximum operating point for wastewater purification. At that point, cells are characterised by high protein (up to 57%DBM) and pigment (up to 6.9%DBM) quotas. During the night, the build-up of proteins at the degradation of intracellular storage components is furthermore visible. Applying the concept of active biomass (cells without storage components), a constant cellular protein (~68%ABM) and nitrogen quota (11.94%ABM) was revealed. A nitrogen spiking experiment clearly showed nitrogen uptake and proliferation during the night period. Based on the experimental data, a window of operation for a continuous WWT process was designed, allowing the hypothesis that continuous WWT using microalgae during day and night operation is possible without the supplementation of artificial light. This revealed the system's capacity to treat WW throughout 24 h applying cell recycling and storage of carbohydrate-rich biomass. At the end of the night, protein-rich biomass is available for further valorisation.
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Affiliation(s)
- Franziska Ortiz Tena
- Karlsruhe Institute of Technology (KIT), Institute of Process Engineering in Life Sciences, Bioprocess Engineering, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
| | - Victoria Bickel
- Karlsruhe Institute of Technology (KIT), Institute of Process Engineering in Life Sciences, Bioprocess Engineering, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Christian Steinweg
- Karlsruhe Institute of Technology (KIT), Institute of Process Engineering in Life Sciences, Bioprocess Engineering, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Clemens Posten
- Karlsruhe Institute of Technology (KIT), Institute of Process Engineering in Life Sciences, Bioprocess Engineering, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
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2
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Oliveira Dos Anjos TB, Abel S, Lindehoff E, Bradshaw C, Sobek A. Assessing the effects of a mixture of hydrophobic contaminants on the algae Rhodomonas salina using the chemical activity concept. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 265:106742. [PMID: 37977012 DOI: 10.1016/j.aquatox.2023.106742] [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: 04/05/2023] [Revised: 10/14/2023] [Accepted: 10/29/2023] [Indexed: 11/19/2023]
Abstract
The production and release of chemicals from human activities are on the rise. Understanding how the aquatic environment is affected by the presence of an unknown number of chemicals is lacking. We employed the chemical activity concept to assess the combined effects of hydrophobic organic contaminants on the phytoplankton species Rodomonas salina. Chemical activity is additive, and refers to the relative saturation of a chemical in the studied matrix. The growth of R. salina was affected by chemical activity, following a chemical activity-response curve, resulting in an Ea50 value of 0.078, which falls within the baseline toxicity range observed in earlier studies. The chlorophyll a content exhibited both increases and decreases with rising chemical activity, with the increase possibly linked to an antioxidant mechanism. Yet, growth inhibition provided more sensitive and robust responses compared to photosynthesis-related endpoints; all measured endpoints correlated with increased chemical activity. Growth inhibition is an ecologically relevant endpoint and integrates thermodynamic principles such as membrane disruption. Our study utilized passive dosing, enabling us to control exposure and determine activities in both the medium and the algae. The concept of chemical activity and our results can be extended to other neutral chemical groups as effects of chemical activity remain independent of the mixture composition.
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Affiliation(s)
| | - Sebastian Abel
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| | - Elin Lindehoff
- Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Clare Bradshaw
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
| | - Anna Sobek
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
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3
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Armin G, Kim J, Inomura K. Saturating growth rate against phosphorus concentration explained by macromolecular allocation. mSystems 2023; 8:e0061123. [PMID: 37642424 PMCID: PMC10654069 DOI: 10.1128/msystems.00611-23] [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: 06/15/2023] [Accepted: 06/28/2023] [Indexed: 08/31/2023] Open
Abstract
IMPORTANCE The Monod equation has been used to represent the relationship between growth rate and the environmental nutrient concentration under the limitation of this respective nutrient. This model often serves as a means to connect microorganisms to their environment, specifically in ecosystem and global models. Here, we use a simple model of a marine microorganism cell to illustrate the model's ability to capture the same relationship as Monod, while highlighting the additional physiological details our model provides. In this study, we focus on the relationship between growth rate and phosphorus concentration and find that RNA allocation largely contributes to the commonly observed trend. This work emphasizes the potential role our model could play in connecting microorganisms to the surrounding environment while using realistic physiological representations.
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Affiliation(s)
- Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA
| | - Jongsun Kim
- School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Brownsville, Texas, USA
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA
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4
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Masuda T, Inomura K, Mareš J, Kodama T, Shiozaki T, Matsui T, Suzuki K, Takeda S, Deutsch C, Prášil O, Furuya K. Coexistence of Dominant Marine Phytoplankton Sustained by Nutrient Specialization. Microbiol Spectr 2023; 11:e0400022. [PMID: 37458590 PMCID: PMC10441275 DOI: 10.1128/spectrum.04000-22] [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: 10/01/2022] [Accepted: 06/07/2023] [Indexed: 08/19/2023] Open
Abstract
Prochlorococcus and Synechococcus are the two dominant picocyanobacteria in the low-nutrient surface waters of the subtropical ocean, but the basis for their coexistence has not been quantitatively demonstrated. Here, we combine in situ microcosm experiments and an ecological model to show that this coexistence can be sustained by specialization in the uptake of distinct nitrogen (N) substrates at low-level concentrations that prevail in subtropical environments. In field incubations, the response of both Prochlorococcus and Synechococcus to nanomolar N amendments demonstrates N limitation of growth in both populations. However, Prochlorococcus showed a higher affinity to ammonium, whereas Synechococcus was more adapted to nitrate uptake. A simple ecological model demonstrates that the differential nutrient preference inferred from field experiments with these genera may sustain their coexistence. It also predicts that as the supply of NO3- decreases, as expected under climate warming, the dominant genera should undergo a nonlinear shift from Synechococcus to Prochlorococcus, a pattern that is supported by subtropical field observations. Our study suggests that the evolution of differential nutrient affinities is an important mechanism for sustaining the coexistence of genera and that climate change is likely to shift the relative abundance of the dominant plankton genera in the largest biomes in the ocean. IMPORTANCE Our manuscript addresses the following fundamental question in microbial ecology: how do different plankton using the same essential nutrients coexist? Prochlorococcus and Synechococcus are the two dominant picocyanobacteria in the low-nutrient surface waters of the subtropical ocean, which support a significant amount of marine primary production. The geographical distributions of these two organisms are largely overlapping, but the basis for their coexistence in these biomes remains unclear. In this study, we combined in situ microcosm experiments and an ecosystem model to show that the coexistence of these two organisms can arise from specialization in the uptake of distinct nitrogen substrates; Prochlorococcus prefers ammonium, whereas Synechococcus prefers nitrate when these nutrients exist at low concentrations. Our framework can be used for simulating and predicting the coexistence in the future ocean and may provide hints toward understanding other similar types of coexistence.
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Affiliation(s)
- Takako Masuda
- Department of Aquatic Bioscience, The University of Tokyo, Bunkyo, Tokyo, Japan
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czechia
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA
| | - Jan Mareš
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czechia
- Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, České Budejovice, Czechia
- Department of Botany, University of South Bohemia, Faculty of Science, České Budejovice, Czechia
| | - Taketoshi Kodama
- Department of Aquatic Bioscience, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Takuhei Shiozaki
- Department of Aquatic Bioscience, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Takato Matsui
- Graduate School of Environmental Science/Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
| | - Koji Suzuki
- Graduate School of Environmental Science/Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
| | - Shigenobu Takeda
- Department of Aquatic Bioscience, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Curtis Deutsch
- Department of Geosciences, Princeton University, Princeton, New Jersey, USA
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czechia
| | - Ken Furuya
- Department of Aquatic Bioscience, The University of Tokyo, Bunkyo, Tokyo, Japan
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5
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Inomura K, Deutsch C, Jahn O, Dutkiewicz S, Follows MJ. Global patterns in marine organic matter stoichiometry driven by phytoplankton ecophysiology. NATURE GEOSCIENCE 2022; 15:1034-1040. [PMID: 36530964 PMCID: PMC9749492 DOI: 10.1038/s41561-022-01066-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/29/2022] [Indexed: 05/28/2023]
Abstract
The proportion of major elements in marine organic matter links cellular processes to global nutrient, oxygen and carbon cycles. Differences in the C:N:P ratios of organic matter have been observed between ocean biomes, but these patterns have yet to be quantified from the underlying small-scale physiological and ecological processes. Here we use an ecosystem model that includes adaptive resource allocation within and between ecologically distinct plankton size classes to attribute the causes of global patterns in the C:N:P ratios. We find that patterns of N:C variation are largely driven by common physiological adjustment strategies across all phytoplankton, while patterns of N:P are driven by ecological selection for taxonomic groups with different phosphorus storage capacities. Although N:C varies widely due to cellular adjustment to light and nutrients, its latitudinal gradient is modest because of depth-dependent trade-offs between nutrient and light availability. Strong latitudinal variation in N:P reflects an ecological balance favouring small plankton with lower P storage capacity in the subtropics, and larger eukaryotes with a higher cellular P storage capacity in nutrient-rich high latitudes. A weaker N:P difference between southern and northern hemispheres, and between the Atlantic and Pacific oceans, reflects differences in phosphate available for cellular storage. Despite simulating only two phytoplankton size classes, the emergent global variability of elemental ratios resembles that of all measured species, suggesting that the range of growth conditions and ecological selection sustain the observed diversity of stoichiometry among phytoplankton.
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Affiliation(s)
- Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI USA
- School of Oceanography, University of Washington, Seattle, WA USA
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Curtis Deutsch
- School of Oceanography, University of Washington, Seattle, WA USA
- Department of Geosciences and High Meadows Environmental Institute, Princeton University, Princeton, NJ USA
| | - Oliver Jahn
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Stephanie Dutkiewicz
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Michael J. Follows
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
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6
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Masuda T, Inomura K, Gao M, Armin G, Kotabová E, Bernát G, Lawrenz-Kendrick E, Lukeš M, Bečková M, Steinbach G, Komenda J, Prášil O. The balance between photosynthesis and respiration explains the niche differentiation between Crocosphaera and Cyanothece. Comput Struct Biotechnol J 2022; 21:58-65. [PMID: 36514336 PMCID: PMC9732122 DOI: 10.1016/j.csbj.2022.11.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/12/2022] [Accepted: 11/13/2022] [Indexed: 11/18/2022] Open
Abstract
Crocosphaera and Cyanothece are both unicellular, nitrogen-fixing cyanobacteria that prefer different environments. Whereas Crocosphaera mainly lives in nutrient-deplete, open oceans, Cyanothece is more common in coastal, nutrient-rich regions. Despite their physiological similarities, the factors separating their niches remain elusive. Here we performed physiological experiments on clone cultures and expand upon a simple ecological model to show that their different niches can be sufficiently explained by the observed differences in their photosynthetic capacities and rates of carbon (C) consumption. Our experiments revealed that Cyanothece has overall higher photosynthesis and respiration rates than Crocosphaera. A simple growth model of these microorganisms suggests that C storage and consumption are previously under-appreciated factors when evaluating the occupation of niches by different marine nitrogen fixers.
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Affiliation(s)
- Takako Masuda
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic,Corresponding authors.
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882, USA
| | - Meng Gao
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882, USA
| | - Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI 02882, USA
| | - Eva Kotabová
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic
| | - Gábor Bernát
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic,Balaton Limnological Research Institute, Eötvös Loránd Research Network (ELKH), Tihany, Hungary
| | - Evelyn Lawrenz-Kendrick
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic
| | - Martin Lukeš
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic
| | - Martina Bečková
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic
| | - Gábor Steinbach
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic,Cellular Imaging Laboratory, Biological Research Center, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
| | - Josef Komenda
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, 37901 Třeboň, Czech Republic,Corresponding authors.
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7
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Kim J, Armin G, Inomura K. Saturating relationship between phytoplankton growth rate and nutrient concentration explained by macromolecular allocation. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100167. [PMID: 36518172 PMCID: PMC9742995 DOI: 10.1016/j.crmicr.2022.100167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/22/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
Phytoplankton account for about a half of photosynthesis in the world, making them a key player in the ecological and biogeochemical systems. One of the key traits of phytoplankton is their growth rate because it indicates their productivity and affects their competitive capability. The saturating relationship between phytoplankton growth rate and environmental nutrient concentration has been widely observed yet the mechanisms behind the relationship remain elusive. Here we use a mechanistic model and metadata of phytoplankton to show that the saturating relationship between growth rate and nitrate concentration can be interpreted by intracellular macromolecular allocation. At low nitrate levels, the diffusive nitrate transport linearly increases with the nitrate concentration, while the internal nitrogen requirement increases with the growth rate, leading to a non-linear increase in the growth rate with nitrate. This increased nitrogen requirement is due to the increased allocation to biosynthetic and photosynthetic molecules. The allocation to these molecules reaches a maximum at high nitrate concentration and the growth rate ceases to increase despite high nitrate availability due to carbon limitation. The produced growth rate and nitrate relationships are consistent with the data of phytoplankton across taxa. Our study provides a macromolecular interpretation of the widely observed growth-nutrient relationship and highlights that the key control of the phytoplankton growth exists within the cell.
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Affiliation(s)
- Jongsun Kim
- School of Earth, Environmental, and Marine Sciences, University of Texas Rio Grande Valley, Brownsville, TX, USA
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
| | - Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
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8
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Modeling the elemental stoichiometry and silica accumulation in diatoms. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100164. [DOI: 10.1016/j.crmicr.2022.100164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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9
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Strzepek RF, Nunn BL, Bach LT, Berges JA, Young EB, Boyd PW. The ongoing need for rates: can physiology and omics come together to co-design the measurements needed to understand complex ocean biogeochemistry? JOURNAL OF PLANKTON RESEARCH 2022; 44:485-495. [PMID: 35898813 PMCID: PMC9310281 DOI: 10.1093/plankt/fbac026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 05/05/2022] [Indexed: 05/16/2023]
Abstract
The necessity to understand the influence of global ocean change on biota has exposed wide-ranging gaps in our knowledge of the fundamental principles that underpin marine life. Concurrently, physiological research has stagnated, in part driven by the advent and rapid evolution of molecular biological techniques, such that they now influence all lines of enquiry in biological oceanography. This dominance has led to an implicit assumption that physiology is outmoded, and advocacy that ecological and biogeochemical models can be directly informed by omics. However, the main modeling currencies are biological rates and biogeochemical fluxes. Here, we ask: how do we translate the wealth of information on physiological potential from omics-based studies to quantifiable physiological rates and, ultimately, to biogeochemical fluxes? Based on the trajectory of the state-of-the-art in biomedical sciences, along with case-studies from ocean sciences, we conclude that it is unlikely that omics can provide such rates in the coming decade. Thus, while physiological rates will continue to be central to providing projections of global change biology, we must revisit the metrics we rely upon. We advocate for the co-design of a new generation of rate measurements that better link the benefits of omics and physiology.
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Affiliation(s)
| | - Brook L Nunn
- Department of Genome Sciences, University of Washington, Foege Building S113 3720 15th Ave NE, Seattle, WA 98195, USA
| | - Lennart T Bach
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7004, Australia
| | - John A Berges
- Department of Biological Sciences and School of Freshwater Sciences, University of Wisconsin-Milwaukee, 3209 N. Maryland Avenue, Milwaukee, WI 53211, USA
| | - Erica B Young
- Department of Biological Sciences and School of Freshwater Sciences, University of Wisconsin-Milwaukee, 3209 N. Maryland Avenue, Milwaukee, WI 53211, USA
| | - Philip W Boyd
- Australian Antarctic Program Partnership (AAPP), Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Hobart, TAS 7004, Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7004, Australia
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10
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Lomas MW, Bates NR, Johnson RJ, Steinberg DK, Tanioka T. Adaptive carbon export response to warming in the Sargasso Sea. Nat Commun 2022; 13:1211. [PMID: 35260567 PMCID: PMC8904855 DOI: 10.1038/s41467-022-28842-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 02/07/2022] [Indexed: 11/30/2022] Open
Abstract
Ocean ecosystem models predict that warming and increased surface ocean stratification will trigger a series of ecosystem events, reducing the biological export of particulate carbon to the ocean interior. We present a nearly three-decade time series from the open ocean that documents a biological response to ocean warming and nutrient reductions wherein particulate carbon export is maintained, counter to expectations. Carbon export is maintained through a combination of phytoplankton community change to favor cyanobacteria with high cellular carbon-to-phosphorus ratios and enhanced shallow phosphorus recycling leading to increased nutrient use efficiency. These results suggest that surface ocean ecosystems may be more responsive and adapt more rapidly to changes in the hydrographic system than is currently envisioned in earth ecosystem models, with positive consequences for ocean carbon uptake. The ability of the ocean’s biota to sequester carbon is thought to be negatively affected by climate change. Here the authors use time-series data in the Sargasso Sea to show that biotic processes can buffer against these negative impacts.
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Affiliation(s)
- Michael W Lomas
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA.
| | - Nicholas R Bates
- Bermuda Institute for Ocean Sciences, St. Georges, Bermuda.,Department of Ocean and Earth Science, University of Southampton, Southampton, UK
| | | | - Deborah K Steinberg
- Virginia Institute of Marine Science, William & Mary, Gloucester Pt., Virginia, VA, USA
| | - Tatsuro Tanioka
- Department of Earth System Science, University of California, Irvine, CA, USA
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11
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Wu Z, Aharonovich D, Roth-Rosenberg D, Weissberg O, Luzzatto-Knaan T, Vogts A, Zoccarato L, Eigemann F, Grossart HP, Voss M, Follows MJ, Sher D. Single-cell measurements and modelling reveal substantial organic carbon acquisition by Prochlorococcus. Nat Microbiol 2022; 7:2068-2077. [PMID: 36329198 PMCID: PMC9712107 DOI: 10.1038/s41564-022-01250-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 09/13/2022] [Indexed: 11/06/2022]
Abstract
Marine phytoplankton are responsible for about half of the photosynthesis on Earth. Many are mixotrophs, combining photosynthesis with heterotrophic assimilation of organic carbon, but the relative contribution of these two lifestyles is unclear. Here single-cell measurements reveal that Prochlorococcus at the base of the photic zone in the Eastern Mediterranean Sea obtain only ~20% of carbon required for growth by photosynthesis. This is supported by laboratory-calibrated calculations based on photo-physiology parameters and compared with in situ growth rates. Agent-based simulations show that mixotrophic cells could grow tens of metres deeper than obligate photo-autotrophs, deepening the nutricline by ~20 m. Time series from the North Atlantic and North Pacific indicate that, during thermal stratification, on average 8-10% of the Prochlorococcus cells live without enough light to sustain obligate photo-autotrophic populations. Together, these results suggest that mixotrophy underpins the ecological success of a large fraction of the global Prochlorococcus population and its collective genetic diversity.
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Affiliation(s)
- Zhen Wu
- grid.116068.80000 0001 2341 2786Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Dikla Aharonovich
- grid.18098.380000 0004 1937 0562Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Dalit Roth-Rosenberg
- grid.18098.380000 0004 1937 0562Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Osnat Weissberg
- grid.18098.380000 0004 1937 0562Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Tal Luzzatto-Knaan
- grid.18098.380000 0004 1937 0562Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Angela Vogts
- grid.423940.80000 0001 2188 0463Leibniz-Institute for Baltic Sea Research, Warnemuende, Germany
| | - Luca Zoccarato
- grid.419247.d0000 0001 2108 8097Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany
| | - Falk Eigemann
- grid.423940.80000 0001 2188 0463Leibniz-Institute for Baltic Sea Research, Warnemuende, Germany
| | - Hans-Peter Grossart
- grid.419247.d0000 0001 2108 8097Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany ,grid.11348.3f0000 0001 0942 1117Institute of Biochemistry and Biology, Potsdam University, Potsdam, Germany
| | - Maren Voss
- grid.423940.80000 0001 2188 0463Leibniz-Institute for Baltic Sea Research, Warnemuende, Germany
| | - Michael J. Follows
- grid.116068.80000 0001 2341 2786Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Daniel Sher
- grid.18098.380000 0004 1937 0562Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
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12
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Inomura K, Masuda T, Eichner M, Rabouille S, Zavřel T, Červený J, Vancová M, Bernát G, Armin G, Claquin P, Kotabová E, Stephan S, Suggett DJ, Deutsch C, Prášil O. Quantifying Cyanothece growth under DIC limitation. Comput Struct Biotechnol J 2021; 19:6456-6464. [PMID: 34938417 PMCID: PMC8665340 DOI: 10.1016/j.csbj.2021.11.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/22/2021] [Accepted: 11/22/2021] [Indexed: 11/26/2022] Open
Abstract
The photoautotrophic, unicellular N2-fixer, Cyanothece, is a model organism that has been widely used to study photosynthesis regulation, the structure of photosystems, and the temporal segregation of carbon (C) and nitrogen (N) fixation in light and dark phases of the diel cycle. Here, we present a simple quantitative model and experimental data that together, suggest external dissolved inorganic carbon (DIC) concentration as a major limiting factor for Cyanothece growth, due to its high C-storage requirement. Using experimental data from a parallel laboratory study as a basis, we show that after the onset of the light period, DIC was rapidly consumed by photosynthesis, leading to a sharp drop in the rate of photosynthesis and C accumulation. In N2-fixing cultures, high rates of photosynthesis in the morning enabled rapid conversion of DIC to intracellular C storage, hastening DIC consumption to levels that limited further uptake. The N2-fixing condition allows only a small fraction of fixed C for cellular growth since a large fraction was reserved in storage to fuel night-time N2 fixation. Our model provides a framework for resolving DIC limitation in aquatic ecosystem simulations, where DIC as a growth-limiting factor has rarely been considered, and importantly emphasizes the effect of intracellular C allocation on growth rate that varies depending on the growth environment.
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Affiliation(s)
- Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA
| | - Takako Masuda
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic
| | - Meri Eichner
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic
| | - Sophie Rabouille
- Sorbonne Université, CNRS, Laboratoire d'Océanographie Microbienne, LOMIC, F-66650 Banyuls-sur-mer, France
| | - Tomáš Zavřel
- Department of Adaptive Biotechnologies, Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - Jan Červený
- Department of Adaptive Biotechnologies, Global Change Research Institute, Czech Academy of Sciences, Brno, Czech Republic
| | - Marie Vancová
- Laboratory of Electron Microscopy, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences and Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Gábor Bernát
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic.,Balaton Limnological Research Institute, Eötvös Loránd Research Network (ELKH), Tihany, Hungary
| | - Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA
| | - Pascal Claquin
- Laboratoire de Biologie des ORganismes et Ecosystèmes Aquatiques (BOREA), UMR 8067, Muséum National d'Histoire Naturelle, CNRS, IRD Sorbonne Université, Université de Caen Normandie, Normandie Université, Esplanade de la Paix, F-14032 Caen, France
| | - Eva Kotabová
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic
| | - Susanne Stephan
- Department Experimental Limnology, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Stechlin, Germany
| | - David J Suggett
- University of Technology Sydney, Climate Change Cluster, Faculty of Science, Ultimo, NSW 2007, Australia
| | - Curtis Deutsch
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Třeboň, Czech Republic
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Armin G, Inomura K. Modeled temperature dependencies of macromolecular allocation and elemental stoichiometry in phytoplankton. Comput Struct Biotechnol J 2021; 19:5421-5427. [PMID: 34712391 PMCID: PMC8515405 DOI: 10.1016/j.csbj.2021.09.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/20/2021] [Accepted: 09/26/2021] [Indexed: 11/23/2022] Open
Abstract
Warming oceans may affect how phytoplankton allocate nutrients to essential cellular processes. Despite the potential impact of such processes on future biogeochemical cycles, questions remain about how temperature affects macromolecular allocation and elemental stoichiometry within phytoplankton cells. Here, we present a macromolecular model of phytoplankton and the effect of increasing temperature on the intracellular allocation of nutrients at a constant growth rate. When temperature increases under nitrogen (N) and phosphorus (P) co-limitation, the model shows less investment in phosphorus-rich RNA molecules relative to nitrogen-rich proteins, leading to a more severe decrease in cellular P:C than N:C causing increased cellular N:P values. Under P limitation, the model shows a similar pattern, but when excess P is available under N limitation, we predict lowered N:P due to the effect of luxury uptake of P. We reflected our model result on the surface ocean showing similar latitudinal patterns in N:P and P:C to observation and other model predictions, suggesting a considerable impact of temperature on constraining the elemental stoichiometry in the ocean.
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Affiliation(s)
- Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, United States
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, United States
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14
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Zavřel T, Schoffman H, Lukeš M, Fedorko J, Keren N, Červený J. Monitoring fitness and productivity in cyanobacteria batch cultures. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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15
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Borella L, Sforza E, Bertucco A. Effect of residence time in continuous photobioreactor on mass and energy balance of microalgal protein production. N Biotechnol 2021; 64:46-53. [PMID: 34087470 DOI: 10.1016/j.nbt.2021.05.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 05/25/2021] [Accepted: 05/28/2021] [Indexed: 10/21/2022]
Abstract
There is increasing interest in new protein sources for the food and feed industry and for the agricultural sector, and microalgae are considered a good alternative, having a high protein content and a well-balanced amino acid profile. However, protein production from microalgae presents several unsolved issues, as the biomass composition changes markedly as a function of cultivation operating conditions. Continuous systems, however, may be properly set to boost the accumulation of protein in the biomass, ensuring stable production. Here, two microalgae and two cyanobacterial species were cultivated in continuous operating photobioreactors (PBR) under nonlimiting nutrient conditions, to study the effects of light intensity and residence time on both biomass and protein productivity at steady state. Although light strongly affected biomass growth inside the PBR, the overall protein pool did not vary in response to irradiance. On the other hand, shorter residence times resulted in protein accumulation of up to 68 % in cyanobacteria, in contrast with green algae, where a minor influence of residence time on biomass composition was observed. Energy balance showed that light conversion to protein decreased with light intensity. Protein content was also related to energy costs for cell maintenance. In conclusion, it is shown that residence time is the key variable to increase protein content and yield of protein production, but its effect depends on the specific species.
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Affiliation(s)
- Lisa Borella
- Department of Industrial Engineering DII, University of Padova, Via Marzolo 9, 35131, Padova, Italy
| | - Eleonora Sforza
- Department of Industrial Engineering DII, University of Padova, Via Marzolo 9, 35131, Padova, Italy.
| | - Alberto Bertucco
- Department of Industrial Engineering DII, University of Padova, Via Marzolo 9, 35131, Padova, Italy
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Inomura K, Deutsch C, Masuda T, Prášil O, Follows MJ. Quantitative models of nitrogen-fixing organisms. Comput Struct Biotechnol J 2020; 18:3905-3924. [PMID: 33335688 PMCID: PMC7733014 DOI: 10.1016/j.csbj.2020.11.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 10/26/2022] Open
Abstract
Nitrogen-fixing organisms are of importance to the environment, providing bioavailable nitrogen to the biosphere. Quantitative models have been used to complement the laboratory experiments and in situ measurements, where such evaluations are difficult or costly. Here, we review the current state of the quantitative modeling of nitrogen-fixing organisms and ways to enhance the bridge between theoretical and empirical studies.
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Affiliation(s)
- Keisuke Inomura
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Curtis Deutsch
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Takako Masuda
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, Třeboň, Czech Republic
| | - Ondřej Prášil
- Institute of Microbiology, The Czech Academy of Sciences, Opatovický mlýn, Třeboň, Czech Republic
| | - Michael J. Follows
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
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