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Jia J, Jiang H, Zhu X, Wang S, Wang L, Liu C, Li W, Huang W. Inorganic carbon utilization strategies of plateau aquatic plants in response to native habitats. PHOTOSYNTHESIS RESEARCH 2024; 162:47-62. [PMID: 39133367 DOI: 10.1007/s11120-024-01115-4] [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: 05/29/2024] [Accepted: 07/29/2024] [Indexed: 08/13/2024]
Abstract
Aquatic plants are a crucial component of the aquatic ecosystem in the Tibetan Plateau region. Researching the adaptability of plateau aquatic plants in photosynthesis to the plateau environment can enhance understanding of the operational mechanisms of plateau ecosystems, thereby providing a scientific basis for the protection and management of plateau aquatic ecosystems. This study presents an investigation of photosynthetic inorganic carbon utilization strategies and photosynthetic efficiency of 17 aquatic plants under natural growing conditions in Niyang River basin on the Tibetan Plateau. In pH-drift experiments, 10 of 17 species were able to utilize HCO3-, and environmental factors like water pH were shown to have a significant effect on the ability of the tested species to utilize HCO3-. Titratable acidity in the leaves of Stuckenia filiformis, Zannichellia palustris, Batrachium bungei, and Myriophyllum spicatum showed significant diurnal fluctuations at certain sampling sites, indicating the presence of CAM. In B. bungei, water pH positively correlated with CAM activity, while CO2 concentration negatively correlated with CAM activity. The chlorophyll fluorescence analysis revealed that aquatic plants inhabiting the Tibetan Plateau exhibited photosynthetic adaptations. In conclusion, the aquatic plants on the Tibetan Plateau employ diverse strategies for utilizing inorganic carbon during photosynthesis, exhibiting their flexible adaptability to the native high-altitude habitats of the Tibetan Plateau.
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Affiliation(s)
- Jiajia Jia
- Key Laboratory of Biodiversity and Environment on the Qinghai-Tibetan Plateau, Ministry of Education, School of Ecology and Environment, Tibet University, Lhasa, 850000, China
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hongsheng Jiang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Xi Zhu
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, HaiKou, 570228, China
| | - Shanwei Wang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Liyuan Wang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | | | - Wei Li
- Key Laboratory of Biodiversity and Environment on the Qinghai-Tibetan Plateau, Ministry of Education, School of Ecology and Environment, Tibet University, Lhasa, 850000, China.
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
- Yani Wetland Ecosystem Positioning Observation and Research Station, Tibet University, Lhasa, China.
| | - Wenmin Huang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
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Gilman IS, Smith JAC, Holtum JAM, Sage RF, Silvera K, Winter K, Edwards EJ. The CAM lineages of planet Earth. ANNALS OF BOTANY 2023; 132:627-654. [PMID: 37698538 PMCID: PMC10799995 DOI: 10.1093/aob/mcad135] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 01/09/2023] [Accepted: 09/11/2023] [Indexed: 09/13/2023]
Abstract
BACKGROUND AND SCOPE The growth of experimental studies of crassulacean acid metabolism (CAM) in diverse plant clades, coupled with recent advances in molecular systematics, presents an opportunity to re-assess the phylogenetic distribution and diversity of species capable of CAM. It has been more than two decades since the last comprehensive lists of CAM taxa were published, and an updated survey of the occurrence and distribution of CAM taxa is needed to facilitate and guide future CAM research. We aimed to survey the phylogenetic distribution of these taxa, their diverse morphology, physiology and ecology, and the likely number of evolutionary origins of CAM based on currently known lineages. RESULTS AND CONCLUSIONS We found direct evidence (in the form of experimental or field observations of gas exchange, day-night fluctuations in organic acids, carbon isotope ratios and enzymatic activity) for CAM in 370 genera of vascular plants, representing 38 families. Further assumptions about the frequency of CAM species in CAM clades and the distribution of CAM in the Cactaceae and Crassulaceae bring the currently estimated number of CAM-capable species to nearly 7 % of all vascular plants. The phylogenetic distribution of these taxa suggests a minimum of 66 independent origins of CAM in vascular plants, possibly with dozens more. To achieve further insight into CAM origins, there is a need for more extensive and systematic surveys of previously unstudied lineages, particularly in living material to identify low-level CAM activity, and for denser sampling to increase phylogenetic resolution in CAM-evolving clades. This should allow further progress in understanding the functional significance of this pathway by integration with studies on the evolution and genomics of CAM in its many forms.
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Affiliation(s)
- Ian S Gilman
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | | | - Joseph A M Holtum
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - Rowan F Sage
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Katia Silvera
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
- Department of Botany & Plant Sciences, University of California, Riverside, CA, USA
| | - Klaus Winter
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
| | - Erika J Edwards
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
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Lin D, Zhou X, Zhao H, Tao X, Yu S, Zhang X, Zang Y, Peng L, Yang L, Deng S, Li X, Mao X, Luan A, He J, Ma J. The Synergistic Mechanism of Photosynthesis and Antioxidant Metabolism between the Green and White Tissues of Ananas comosus var. bracteatus Chimeric Leaves. Int J Mol Sci 2023; 24:ijms24119238. [PMID: 37298190 DOI: 10.3390/ijms24119238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/30/2023] [Accepted: 05/03/2023] [Indexed: 06/12/2023] Open
Abstract
Ananas comosus var. bracteatus (Ac. bracteatus) is a typical leaf-chimeric ornamental plant. The chimeric leaves are composed of central green photosynthetic tissue (GT) and marginal albino tissue (AT). The mosaic existence of GT and AT makes the chimeric leaves an ideal material for the study of the synergistic mechanism of photosynthesis and antioxidant metabolism. The daily changes in net photosynthetic rate (NPR) and stomatal conductance (SCT) of the leaves indicated the typical crassulacean acid metabolism (CAM) characteristic of Ac. bracteatus. Both the GT and AT of chimeric leaves fixed CO2 during the night and released CO2 from malic acid for photosynthesis during the daytime. The malic acid content and NADPH-ME activity of the AT during the night was significantly higher than that of GT, which suggests that the AT may work as a CO2 pool to store CO2 during the night and supply CO2 for photosynthesis in the GT during the daytime. Furthermore, the soluble sugar content (SSC) in the AT was significantly lower than that of GT, while the starch content (SC) of the AT was apparently higher than that of GT, indicating that AT was inefficient in photosynthesis but may function as a photosynthate sink to help the GT maintain high photosynthesis activity. Additionally, the AT maintained peroxide balance by enhancing the non-enzymatic antioxidant system and antioxidant enzyme system to avoid antioxidant damage. The enzyme activities of reductive ascorbic acid (AsA) and the glutathione (GSH) cycle (except DHAR) and superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were enhanced, apparently to make the AT grow normally. This study indicates that, although the AT of the chimeric leaves was inefficient at photosynthesis because of the lack of chlorophyll, it can cooperate with the GT by working as a CO2 supplier and photosynthate store to enhance the photosynthetic ability of GT to help chimeric plants grow well. Additionally, the AT can avoid peroxide damage caused by the lack of chlorophyll by enhancing the activity of the antioxidant system. The AT plays an active role in the normal growth of the chimeric leaves.
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Affiliation(s)
- Dongpu Lin
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Xuzixin Zhou
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Huan Zhao
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Xiaoguang Tao
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Sanmiao Yu
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Xiaopeng Zhang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Yaoqiang Zang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Lingli Peng
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Li Yang
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Shuyue Deng
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Xiyan Li
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Xinjing Mao
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
| | - Aiping Luan
- Tropical Crop Genetic Resources Institute, Chinese Academy of Agricultural Science, Haikou 571101, China
| | - Junhu He
- Tropical Crop Genetic Resources Institute, Chinese Academy of Agricultural Science, Haikou 571101, China
| | - Jun Ma
- College of Landscape Architecture, Sichuan Agricultural University, Chengdu 611100, China
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Liao Z, Li P, Zhou J, Li W, Jiang HS. Different photosynthetic inorganic carbon utilization strategies in the heteroblastic leaves of an aquatic plant Ottelia ovalifolia. FRONTIERS IN PLANT SCIENCE 2023; 14:1142848. [PMID: 37035085 PMCID: PMC10081514 DOI: 10.3389/fpls.2023.1142848] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/03/2023] [Indexed: 06/19/2023]
Abstract
The leaves of the heteroblastic aquatic plant Ottelia ovalifolia faces submerged and aerial environments during its life history. However, the acclimation of the submerged leaves and floating leaves to these two environments in morphology, physiology, and biochemistry remain unclear. In the present study, we investigated the acclimation of the CO2-concentrating mechanisms in these two types of leaves. We found that the submerged leaves were longer, narrower, and thinner than the floating leaves, which increased the specific surface area of the leaves and lead to better absorption of the inorganic carbon underwater. Meanwhile, the floating leaves absorbed atmospheric CO2 directly through the stomata to acclimate to the aerial environment. Both the leaf types had the ability to use HCO 3 - , but the capacity in submerged leaves was stronger than that in floating leaves. The extracellular carbonic anhydrase and anion exchanger were responsible for the HCO 3 - use in both types of leaves. The higher ratio of chlorophyll a/b and content of anthocyanin in floating leaves than that in submerged leaves indicated that the acclimation of aerial and submerged photosynthesis depended on changes in the photosynthetic pigments. Based on the stable carbon isotope ratio, key enzyme activities of the C4 pathway indicated that submerged leaves might have the ability to perform C4 metabolism while floating leaves only performed C3 metabolism. In summary, O. ovalifolia acclimates to submerged and aerial environments through changes in morphology, physiology, and biochemistry during different growth stages.
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Affiliation(s)
- Zuying Liao
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Pengpeng Li
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, Haikou, China
| | - Jingzhe Zhou
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei Li
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Research Center for Ecology, College of Science, Tibet University, Lhasa, China
| | - Hong Sheng Jiang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
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Wang W, Yuan L, Zhou J, Zhu X, Liao Z, Yin L, Li W, Jiang HS. Inorganic carbon utilization: A target of silver nanoparticle toxicity on a submerged macrophyte. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 318:120906. [PMID: 36549447 DOI: 10.1016/j.envpol.2022.120906] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/12/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
Submerged macrophytes play an important role in the global carbon cycle through diversified pathways of inorganic carbon (Ci) utilization distinct from terrestrial plants. However, the effects of silver nanoparticles (AgNPs), an emerging contaminant, were unknown on the Ci utilization of submerged macrophytes. In Ottelia alismoides, the only known submerged macrophyte with three pathways of Ci utilization, before absorption, AgNPs inhibited the external carbonic anhydrase activity thus reducing the capacity of the plant to use HCO3-. After entering the plant, AgNPs mainly aggregated at the cell wall and in the chloroplast. The internalized AgNPs inhibited ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco) activity blocking CO2 fixation and disturbed C4 and crassulacean acid metabolism (CAM) by inhibiting phosphoenolpyruvate carboxylase (PEPC), pyruvate phosphate dikinase (PPDK), and NAD-dependent malic enzyme (NAD-ME) activities to alter intracellular malate biosynthesis and decarboxylation. Overall, our findings indicate that the Ci utilization of the submerged macrophyte is a target of AgNPs toxicity that might affect the carbon cycle in aquatic systems.
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Affiliation(s)
- Wanwan Wang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China; College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, China
| | - Longyi Yuan
- College of Horticulture and Gardening, Yangtze University, Jingzhou, 434025, China
| | - Jingzhe Zhou
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Xi Zhu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, HaiKou, 570228, China
| | - Zuying Liao
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Liyan Yin
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, School of Life Sciences, Hainan University, HaiKou, 570228, China
| | - Wei Li
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hong Sheng Jiang
- Aquatic Plant Research Center, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
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Maberly SC, Stott A, Gontero B. The differential ability of two species of seagrass to use carbon dioxide and bicarbonate and their modelled response to rising concentrations of inorganic carbon. FRONTIERS IN PLANT SCIENCE 2022; 13:936716. [PMID: 36388529 PMCID: PMC9648567 DOI: 10.3389/fpls.2022.936716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Seagrass meadows are one of the most productive ecosystems on the planet, but their photosynthesis rate may be limited by carbon dioxide but mitigated by exploiting the high concentration of bicarbonate in the ocean using different active processes. Seagrasses are declining worldwide at an accelerating rate because of numerous anthropogenic pressures. However, rising ocean concentrations of dissolved inorganic carbon, caused by increases in atmospheric carbon dioxide, may benefit seagrass photosynthesis. Here we compare the ability of two seagrass from the Mediterranean Sea, Posidonia oceanica (L.) Delile and Zostera marina L., to use carbon dioxide and bicarbonate at light saturation, and model how increasing concentrations of inorganic carbon affect their photosynthesis rate. pH-drift measurements confirmed that both species were able to use bicarbonate in addition to carbon dioxide, but that Z. marina was more effective than P. oceanica. Kinetic experiments showed that, compared to Z. marina, P. oceanica had a seven-fold higher affinity for carbon dioxide and a 1.6-fold higher affinity for bicarbonate. However, the maximal rate of bicarbonate uptake in Z. marina was 2.1-fold higher than in P. oceanica. In equilibrium with 410 ppm carbon dioxide in the atmosphere, the modelled rates of photosynthesis by Z. marina were slightly higher than P. oceanica, less carbon limited and depended on bicarbonate to a greater extent. This greater reliance by Z. marina is consistent with its less depleted 13C content compared to P. oceanica. Modelled photosynthesis suggests that both species would depend on bicarbonate alone at an atmospheric carbon dioxide partial pressure of 280 ppm. P. oceanica was projected to benefit more than Z. marina with increasing atmospheric carbon dioxide partial pressures, and at the highest carbon dioxide scenario of 1135 ppm, would have higher rates of photosynthesis and be more saturated by inorganic carbon than Z. marina. In both species, the proportional reliance on bicarbonate declined markedly as carbon dioxide concentrations increased and in P. oceanica carbon dioxide would become the major source of inorganic carbon.
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Affiliation(s)
| | - Andrew W. Stott
- UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, United Kingdom
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Chmara R, Pronin E, Szmeja J. Functional macrophyte trait variation as a response to the source of inorganic carbon acquisition. PeerJ 2021; 9:e12584. [PMID: 34917426 PMCID: PMC8643105 DOI: 10.7717/peerj.12584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 11/11/2021] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND This study aims to compare variation in a range of aquatic macrophyte species leaf traits into three carbon acquisition groups: HCO3 -, free CO2 and atmospheric CO2. METHODS The leaf functional traits were measured for 30 species from 30 softwater lakes. Macrophyte species were classified into (1) free CO2, (2) atmospheric CO2 and (3) bicarbonate HCO3 - groups. In each lake we collected water samples and measured eight environmental variables: depth, Secchi depth, photosynthetically active radiation (PAR), pH of water, conductivity, calcium concentration, total nitrogen and total phosphorus. In this study we applied the RLQ analysis to investigate the relationships between species functional traits (Q) and their relationship with environmental variables (R) constrained by species abundance (L). RESULTS The results showed that: (1) Aquatic macrophytes exhibited high leaf trait variations as a response to different inorganic carbon acquisition; (2) Traits of leaves refer to the acquisition of carbon for photosynthesis and serve to maximise this process; (3) In the wide softwater habitat, macrophyte species exhibited an extreme range of leaf economic spectrum (leaf area, leaf dry weight and specific leaf area) and wide range of shape trait expressed as circularity; (4) Macrophyte leaf traits are the result of adaptation to carbon acquisition in ambient environment.
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Affiliation(s)
- Rafał Chmara
- Department of Plant Ecology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Eugeniusz Pronin
- Department of Plant Ecology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Józef Szmeja
- Department of Plant Ecology, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
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Sudová R, Rydlová J, Čtvrtlíková M, Kohout P, Oehl F, Voříšková J, Kolaříková Z. Symbiosis of isoetid plant species with arbuscular mycorrhizal fungi under aquatic versus terrestrial conditions. MYCORRHIZA 2021; 31:273-288. [PMID: 33486575 DOI: 10.1007/s00572-020-01017-y] [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: 09/07/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) colonize the roots of numerous aquatic and wetland plants, but the establishment and functioning of mycorrhizal symbiosis in submerged habitats have received only little attention. Three pot experiments were conducted to study the interaction of isoetid plants with native AMF. In the first experiment, arbuscular mycorrhizal (AM) symbiosis did not establish in roots of Isoëtes echinospora and I. lacustris, while Littorella uniflora roots were highly colonized. Shoot and root biomass of L. uniflora were, however, not affected by AMF inoculation, and only one of nine AMF isolates significantly increased shoot P concentration. In the second experiment, we compared colonization by three Glomus tetrastratosum isolates of different cultivation history and origin (aquatic versus terrestrial) and their effects on L. uniflora growth and phosphorus nutrition under submerged versus terrestrial conditions. The submerged cultivation considerably slowed, but did not inhibit mycorrhizal root colonization, regardless of isolate identity. Inoculation with any AMF isolate improved plant growth and P uptake under terrestrial, but not submerged conditions. In the final experiment, we compared the communities of AMF established in two cultivation regimes of trap cultures with lake sediments, either submerged on L. uniflora or terrestrial on Zea mays. After 2-year cultivation, we did not detect a significant effect of cultivation regime on AMF community composition. In summary, although submerged conditions do not preclude the development of functional AM symbiosis, the contribution of these symbiotic fungi to the fitness of their hosts seems to be considerably less than under terrestrial conditions.
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Affiliation(s)
- Radka Sudová
- Institute of Botany, The Czech Academy of Sciences, 242 43, Průhonice, Czech Republic.
| | - Jana Rydlová
- Institute of Botany, The Czech Academy of Sciences, 242 43, Průhonice, Czech Republic
| | - Martina Čtvrtlíková
- Biology Centre, Institute of Hydrobiology, The Czech Academy of Sciences, 370 05, České Budějovice, Czech Republic
| | - Petr Kohout
- Institute of Botany, The Czech Academy of Sciences, 242 43, Průhonice, Czech Republic
- Institute of Microbiology, The Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague, Czech Republic
- Department of Experimental Plant Biology, Faculty of Science, Charles University, 128 44, Prague, Czech Republic
| | - Fritz Oehl
- Agroscope, Competence Division for Plants and Plant Products, Ecotoxicology, 8820, Wädenswil, Switzerland
| | - Jana Voříšková
- Institute of Microbiology, The Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague, Czech Republic
| | - Zuzana Kolaříková
- Institute of Botany, The Czech Academy of Sciences, 242 43, Průhonice, Czech Republic
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Liu D, Hu R, Zhang J, Guo HB, Cheng H, Li L, Borland AM, Qin H, Chen JG, Muchero W, Tuskan GA, Yang X. Overexpression of an Agave Phospho enolpyruvate Carboxylase Improves Plant Growth and Stress Tolerance. Cells 2021; 10:582. [PMID: 33800849 PMCID: PMC7999111 DOI: 10.3390/cells10030582] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/16/2021] [Accepted: 02/18/2021] [Indexed: 12/29/2022] Open
Abstract
It has been challenging to simultaneously improve photosynthesis and stress tolerance in plants. Crassulacean acid metabolism (CAM) is a CO2-concentrating mechanism that facilitates plant adaptation to water-limited environments. We hypothesized that the ectopic expression of a CAM-specific phosphoenolpyruvate carboxylase (PEPC), an enzyme that catalyzes primary CO2 fixation in CAM plants, would enhance both photosynthesis and abiotic stress tolerance. To test this hypothesis, we engineered a CAM-specific PEPC gene (named AaPEPC1) from Agave americana into tobacco. In comparison with wild-type and empty vector controls, transgenic tobacco plants constitutively expressing AaPEPC1 showed a higher photosynthetic rate and biomass production under normal conditions, along with significant carbon metabolism changes in malate accumulation, the carbon isotope ratio δ13C, and the expression of multiple orthologs of CAM-related genes. Furthermore, AaPEPC1 overexpression enhanced proline biosynthesis, and improved salt and drought tolerance in the transgenic plants. Under salt and drought stress conditions, the dry weight of transgenic tobacco plants overexpressing AaPEPC1 was increased by up to 81.8% and 37.2%, respectively, in comparison with wild-type plants. Our findings open a new door to the simultaneous improvement of photosynthesis and stress tolerance in plants.
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Affiliation(s)
- Degao Liu
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Rongbin Hu
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
| | - Jin Zhang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Hao-Bo Guo
- Department of Computer Science and Engineering, SimCenter, University of Tennessee Chattanooga, Chattanooga, TN 37403, USA; (H.-B.G.); (H.Q.)
| | - Hua Cheng
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
| | - Linling Li
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
| | - Anne M. Borland
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Hong Qin
- Department of Computer Science and Engineering, SimCenter, University of Tennessee Chattanooga, Chattanooga, TN 37403, USA; (H.-B.G.); (H.Q.)
| | - Jin-Gui Chen
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Wellington Muchero
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Gerald A. Tuskan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Xiaohan Yang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; (D.L.); (R.H.); (J.Z.); (H.C.); (L.L.); (A.M.B.); (J.-G.C.); (W.M.); (G.A.T.)
- The Center for Bioenergy Innovation (CBI), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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Huang W, Han S, Jiang H, Gu S, Li W, Gontero B, Maberly SC. External α-carbonic anhydrase and solute carrier 4 are required for bicarbonate uptake in a freshwater angiosperm. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6004-6014. [PMID: 32721017 DOI: 10.1093/jxb/eraa351] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
The freshwater monocot Ottelia alismoides is the only known species to operate three CO2-concentrating mechanisms (CCMs): constitutive bicarbonate (HCO3-) use, C4 photosynthesis, and facultative Crassulacean acid metabolism, but the mechanism of HCO3- use is unknown. We found that the inhibitor of an anion exchange protein, 4,4'-diisothio-cyanatostilbene-2,2'-disulfonate (DIDS), prevented HCO3- use but also had a small effect on CO2 uptake. An inhibitor of external carbonic anhydrase (CA), acetazolamide (AZ), reduced the affinity for CO2 uptake but also prevented HCO3- use via an effect on the anion exchange protein. Analysis of mRNA transcripts identified a homologue of solute carrier 4 (SLC4) responsible for HCO3- transport, likely to be the target of DIDS, and a periplasmic α-carbonic anhydrase 1 (α-CA1). A model to quantify the contribution of the three different pathways involved in inorganic carbon uptake showed that passive CO2 diffusion dominates inorganic carbon uptake at high CO2 concentrations. However, as CO2 concentrations fall, two other pathways become predominant: conversion of HCO3- to CO2 at the plasmalemma by α-CA1 and transport of HCO3- across the plasmalemma by SLC4. These mechanisms allow access to a much larger proportion of the inorganic carbon pool and continued photosynthesis during periods of strong carbon depletion in productive ecosystems.
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Affiliation(s)
- Wenmin Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- Aix Marseille Univ CNRS, BIP UMR 7281, IMM, FR 3479, 31 Chemin Joseph Aiguier, Marseille Cedex 20, France
| | - Shijuan Han
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Hongsheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
| | - Shuping Gu
- Shanghai Sequen Bio-info Studio, Shanghai, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
| | - Brigitte Gontero
- Aix Marseille Univ CNRS, BIP UMR 7281, IMM, FR 3479, 31 Chemin Joseph Aiguier, Marseille Cedex 20, France
| | - Stephen C Maberly
- Lake Ecosystems Group, UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, UK
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Huang W, Jin Q, Yin L, Li W. Responses of CO 2-concentrating mechanisms and photosynthetic characteristics in aquatic plant Ottelia alismoides following cadmium stress under low CO 2. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 202:110955. [PMID: 32800229 DOI: 10.1016/j.ecoenv.2020.110955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/24/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
The effects of cadmium (Cd) have been investigated in an aquatic plant Ottelia alismoides grown under low CO2. Under low CO2, no Cd treated O. alismoides operated three carbon dioxide-concentrating mechanisms (CCMs) efficiently, including HCO3- acquisition, C4 and CAM photosynthesis. After 4 days of treatment with 200 μM and 2000 μM Cd, O. alismoides exhibited an elevated Cd accumulation along with the increasing Cd concentration. Both Cd treatments induced appreciable phytotoxicities in O. alismoides. The leaves showed chlorosis symptoms and the anatomy as well as chloroplast ultrastructure were obviously damaged. Significant decreases in the content of pigments, chlorophyll fluorescence (Fv/Fm and Yield of PS II) and carbon isotope ratio (δ13C) were measured in leaf extracts of O. alismoides grown with both concentrations of Cd. In addition, the pH-drift technique showed that both Cd-treated O. alismoides plants could not uptake HCO3-. The maximum and minimum acidity in Cd-exposed O. alismoides were greatly decreased and the diurnal change of acidity was absent in both Cd treated plants. Furthermore, significant decreases in ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), pyruvate phosphate dikinase (PPDK) and phosphoenolpyruvate carboxylase (PEPC) activities were also found at Cd treated O. alismoides plants, indicating the disturbance within C4 cycle. The alterations in the functionality of CCMs in O. alismoides induced by Cd might be related with the inhibition of the enzymes such as carbonic anhydrase (CA) and PEPC involved in inorganic carbon fixation, and the destruction of chloroplasts, as well as the re-allocation of energy and nutrients involved in CCMs and Cd detoxification.
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Affiliation(s)
- Wenmin Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, 430074, China; Aix Marseille Univ CNRS, BIP UMR 7281, IMM, FR 3479, 31 Chemin Joseph Aiguier, 13402, Marseille Cedex 20, France
| | - Quan Jin
- School of Life and Pharmaceutical Sciences, Hainan University, HaiKou, 570228, China
| | - Liyan Yin
- School of Life and Pharmaceutical Sciences, Hainan University, HaiKou, 570228, China.
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, 430074, China.
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Huang W, Han S, Xing Z, Li W. Responses of Leaf Anatomy and CO 2 Concentrating Mechanisms of the Aquatic Plant Ottelia cordata to Variable CO 2. FRONTIERS IN PLANT SCIENCE 2020; 11:1261. [PMID: 32922428 PMCID: PMC7457065 DOI: 10.3389/fpls.2020.01261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Acclimation to variable CO2 was studied in floating leaves of the freshwater monocot Ottelia cordata grown in either low or high CO2. The most striking anatomical variations responding to high CO2 included the enlarged upper epidermal cells and the decreased area of epidermal chloroplasts. Stomata that distributed on the upper surface, and the stomatic chamber area, showed no significant response to high CO2. pH-drift experiments indicated that floating leaves of O. cordata were able to use bicarbonate regardless of CO2 concentrations. Photosynthetic enzyme activities and patterns of organic acids fluctuation confirmed that floating leaves of O. cordata can operate CAM only at low CO2, and perform C4-like metabolism at both high and low CO2. Overall, the present results imply that the floating leaves of O. cordata does not just rely on the atmospheric CO2 for its inorganic carbon, but is also dependent on CO2 and bicarbonate in the water. By showing these effects of CO2 variation, we highlight the need for further experimental studies on the regulatory mechanisms in O. cordata floating leaves, that prevent futile cycling among the three CO2 concentrating mechanisms (bicarbonate use, C4, and CAM metabolism) and the strategy for exploiting atmospheric CO2, as well as studies on the detailed biochemical pathway for C4 and CAM metabolism in this species.
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Affiliation(s)
- Wenmin Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- Aix Marseille Univ CNRS, BIP UMR 7281, IMM, FR 3479, Marseille, France
| | - Shijuan Han
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhenfei Xing
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
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Han S, Maberly SC, Gontero B, Xing Z, Li W, Jiang H, Huang W. Structural basis for C4 photosynthesis without Kranz anatomy in leaves of the submerged freshwater plant Ottelia alismoides. ANNALS OF BOTANY 2020; 125:869-879. [PMID: 31942934 PMCID: PMC7218808 DOI: 10.1093/aob/mcaa005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Ottelia alismoides (Hydrocharitaceae) is a freshwater macrophyte that, unusually, possesses three different CO2-concentrating mechanisms. Here we describe its leaf anatomy and chloroplast ultrastructure, how these are altered by CO2 concentration and how they may underlie C4 photosynthesis. METHODS Light and transmission electron microscopy were used to study the anatomy of mature leaves of O. alismoides grown at high and low CO2 concentrations. Diel acid change and the activity of phosphoenolpyruvate carboxylase were measured to confirm that CAM activity and C4 photosynthesis were present. KEY RESULTS When O. alismoides was grown at low CO2, the leaves performed both C4 and CAM photosynthesis whereas at high CO2 leaves used C4 photosynthesis. The leaf comprised an upper and lower layer of epidermal cells separated by a large air space occupying about 22 % of the leaf transverse-section area, and by mesophyll cells connecting the two epidermal layers. Kranz anatomy was absent. At low CO2, chloroplasts in the mesophyll cells were filled with starch even at the start of the photoperiod, while epidermal chloroplasts contained small starch grains. The number of chloroplasts in the epidermis was greater than in the mesophyll cells. At high CO2, the structure was unchanged but the thicknesses of the two epidermal layers, the air space, mesophyll and the transverse-section area of cells and air space were greater. CONCLUSIONS Leaves of O. alismoides have epidermal and mesophyll cells that contain chloroplasts and large air spaces but lack Kranz anatomy. The high starch content of mesophyll cells suggests they may benefit from an internal source of CO2, for example via C4 metabolism, and are also sites of starch storage. The air spaces may help in the recycling of decarboxylated or respired CO2. The structural similarity of leaves at low and high CO2 is consistent with the constitutive nature of bicarbonate and C4 photosynthesis. There is sufficient structural diversity within the leaf of O. alismoides to support dual-cell C4 photosynthesis even though Kranz anatomy is absent.
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Affiliation(s)
- Shijuan Han
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Stephen C Maberly
- Lake Ecosystems Group, UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster, UK
| | - Brigitte Gontero
- Aix Marseille Univ CNRS, BIP UMR, IMM, FR, Chemin Joseph Aiguier, Marseille Cedex, France
| | - Zhenfei Xing
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, China
| | - Hongsheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Wenmin Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Aix Marseille Univ CNRS, BIP UMR, IMM, FR, Chemin Joseph Aiguier, Marseille Cedex, France
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Yang L, Li H, Zhang Y, Jiao N. Environmental risk assessment of triazine herbicides in the Bohai Sea and the Yellow Sea and their toxicity to phytoplankton at environmental concentrations. ENVIRONMENT INTERNATIONAL 2019; 133:105175. [PMID: 31629173 DOI: 10.1016/j.envint.2019.105175] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 09/04/2019] [Accepted: 09/08/2019] [Indexed: 06/10/2023]
Abstract
Herbicides have been increasingly used worldwide and a large amount of herbicide residue eventually enters the ocean via groundwater or surface run-off every year. However, the global coastal pollution status of herbicides and their negative impact on marine life (especially phytoplankton) in natural environmental concentrations are poorly understood except for few special environments (e.g. the Great Barrier Reef, Australia). Our field investigation of the distribution of ten triazine herbicides in the Bohai Sea and the Yellow Sea of China revealed that the concentrations of triazine herbicides exceeded the "No Observed Effect Concentrations" for phytoplankton. Their total concentrations could be as high as 6.61 nmol L-1. Based on the concentration addition model, the toxicity of herbicide homologues is usually cumulative, and the combined toxicity of these ten triazine herbicides could cause 13.2% inhibition on the chlorophyll a fluorescence intensity of a representative diatom species Phaeodactylum tricornutum Pt-1, which corresponds roughly to the toxicity of atrazine in an equivalent concentration of 14.08 nmol L-1. Atrazine in this equivalent-effect concentration could greatly inhibit the growth of cells, the maximum quantum efficiency of photosystem II (Fv/Fm), and nutrient absorption of Phaeodactylum tricornutum Pt-1. Transcriptome analysis revealed that multiple metabolic pathways (Calvin cycle, tricarboxylic acid (TCA) cycle, glycolysis/gluconeogenesis, etc.) related with photosynthesis and carbon metabolism were greatly disturbed, which might ultimately influence the primary productivity of coastal waters. Moreover, with the values of its bioaccumulation factor ranging from 69.6 to 118.9, atrazine was found to be accumulated in algal cells, which indicates that herbicide pollution might eventually affect the marine food web and even threaten the seafood safety of human beings.
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Affiliation(s)
- Liqiang Yang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Hongmei Li
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
| | - Yongyu Zhang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361101, China
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Huang WM, Shao H, Zhou SN, Zhou Q, Fu WL, Zhang T, Jiang HS, Li W, Gontero B, Maberly SC. Different CO 2 acclimation strategies in juvenile and mature leaves of Ottelia alismoides. PHOTOSYNTHESIS RESEARCH 2018; 138:219-232. [PMID: 30078074 DOI: 10.1007/s11120-018-0568-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 07/28/2018] [Indexed: 06/08/2023]
Abstract
The freshwater macrophyte, Ottelia alismoides, is a bicarbonate user performing C4 photosynthesis in the light, and crassulacean acid metabolism (CAM) when acclimated to low CO2. The regulation of the three mechanisms by CO2 concentration was studied in juvenile and mature leaves. For mature leaves, the ratios of phosphoenolpyruvate carboxylase (PEPC) to ribulose-bisphosphate carboxylase/oxygenase (Rubisco) are in the range of that of C4 plants regardless of CO2 concentration (1.5-2.5 at low CO2, 1.8-3.4 at high CO2). In contrast, results for juvenile leaves suggest that C4 is facultative and only present under low CO2. pH-drift experiments showed that both juvenile and mature leaves can use bicarbonate irrespective of CO2 concentration, but mature leaves have a significantly greater carbon-extracting ability than juvenile leaves at low CO2. At high CO2, neither juvenile nor mature leaves perform CAM as indicated by lack of diurnal acid fluctuation. However, CAM was present at low CO2, though the fluctuation of titratable acidity in juvenile leaves (15-17 µequiv g-1 FW) was slightly but significantly lower than in mature leaves (19-25 µequiv g-1 FW), implying that the capacity to perform CAM increases as leaves mature. The increased CAM activity is associated with elevated PEPC activity and large diel changes in starch content. These results show that in O. alismoides, carbon-dioxide concentrating mechanisms are more effective in mature compared to juvenile leaves, and C4 is facultative in juvenile leaves but constitutive in mature leaves.
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Affiliation(s)
- Wen Min Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Hui Shao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Aix Marseille Univ, CNRS, BIP, UMR 7281, 31 Chemin Joseph Aiguier, CS70071, 13402, Marseille Cedex 09, France
| | - Si Ning Zhou
- Sino-Danish Center, The University of Chinese Academy of Sciences, Beijing, 101400, China
| | - Qin Zhou
- School of Resources and Environmental Science, Hubei University, Wuhan, 430074, China
| | - Wen Long Fu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Ting Zhang
- School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Hong Sheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Brigitte Gontero
- Aix Marseille Univ, CNRS, BIP, UMR 7281, 31 Chemin Joseph Aiguier, CS70071, 13402, Marseille Cedex 09, France.
| | - Stephen C Maberly
- Lake Ecosystems Group, Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, Bailrigg, LA1 4AP, UK.
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Trade-offs and Synergies in the Structural and Functional Characteristics of Leaves Photosynthesizing in Aquatic Environments. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/978-3-319-93594-2_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
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17
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Functional Anatomical Traits of the Photosynthetic Organs of Plants with Crassulacean Acid Metabolism. THE LEAF: A PLATFORM FOR PERFORMING PHOTOSYNTHESIS 2018. [DOI: 10.1007/978-3-319-93594-2_10] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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Shao H, Gontero B, Maberly SC, Jiang HS, Cao Y, Li W, Huang WM. Responses of Ottelia alismoides, an aquatic plant with three CCMs, to variable CO2 and light. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3985-3995. [PMID: 28369629 PMCID: PMC5853927 DOI: 10.1093/jxb/erx064] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 02/03/2017] [Indexed: 05/29/2023]
Abstract
Ottelia alismoides is a constitutive C4 plant and bicarbonate user, and has facultative crassulacean acid metabolism (CAM) at low CO2. Acclimation to a factorial combination of light and CO2 showed that the ratio of phosphoenolpyruvate carboxylase (PEPC) to ribulose-bisphosphate carboxylase/oxygenase (Rubisco) (>5) is in the range of that of C4 plants. This and short-term response experiments showed that the activity of PEPC and pyruvate phosphate dikinase (PPDK) was high even at the end of the night, consistent with night-time acid accumulation and daytime carbon fixation. The diel acidity change was maximal at high light and low CO2 at 17-25 µequiv g-1 FW. Decarboxylation proceeded at ~2-3 µequiv g-1 FW h-1, starting at the beginning of the photoperiod, but did not occur at high CO2; the rate was greater at high, compared with low light. There was an inverse relationship between starch formation and acidity loss. Acidity changes account for up to 21% of starch production and stimulate early morning photosynthesis, but night-time accumulation of acid traps <6% of respiratory carbon release. Ottelia alismoides is the only known species to operate CAM and C4 in the same tissue, and one of only two known aquatic species to operate CAM and bicarbonate use.
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Affiliation(s)
- Hui Shao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Brigitte Gontero
- Aix Marseille Univ CNRS, BIP UMR, IMM, FR, Chemin Joseph Aiguier, Marseille Cedex, France
| | - Stephen C Maberly
- Lake Ecosystems Group, Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, UK
| | - Hong Sheng Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Aix Marseille Univ CNRS, BIP UMR, IMM, FR, Chemin Joseph Aiguier, Marseille Cedex, France
| | - Yu Cao
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Wei Li
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Wen Min Huang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Hubei Key Laboratory of Wetland Evolution & Ecological Restoration, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
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Maberly SC, Gontero B. Ecological imperatives for aquatic CO2-concentrating mechanisms. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3797-3814. [PMID: 28645178 DOI: 10.1093/jxb/erx201] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In aquatic environments, the concentration of inorganic carbon is spatially and temporally variable and CO2 can be substantially oversaturated or depleted. Depletion of CO2 plus low rates of diffusion cause inorganic carbon to be more limiting in aquatic than terrestrial environments, and the frequency of species with a CO2-concentrating mechanism (CCM), and their contribution to productivity, is correspondingly greater. Aquatic photoautotrophs may have biochemical or biophysical CCMs and exploit CO2 from the sediment or the atmosphere. Though partly constrained by phylogeny, CCM activity is related to environmental conditions. CCMs are absent or down-regulated when their increased energy costs, lower CO2 affinity, or altered mineral requirements outweigh their benefits. Aquatic CCMs are most widespread in environments with low CO2, high HCO3-, high pH, and high light. Freshwater species are generally less effective at inorganic carbon removal than marine species, but have a greater range of ability to remove carbon, matching the environmental variability in carbon availability. The diversity of CCMs in seagrasses and marine phytoplankton, and detailed mechanistic studies on larger aquatic photoautotrophs are understudied. Strengthening the links between ecology and CCMs will increase our understanding of the mechanisms underlying ecological success and will place mechanistic studies in a clearer ecological context.
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Affiliation(s)
- Stephen C Maberly
- Lake Ecosystems Group, Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - Brigitte Gontero
- Aix Marseille Univ, CNRS, BIP, UMR 7281, IMM, FR 3479, 31 Chemin J. Aiguier, 13 402 Marseille, Cedex 20, France
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20
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Maberly SC, Berthelot SA, Stott AW, Gontero B. Adaptation by macrophytes to inorganic carbon down a river with naturally variable concentrations of CO2. JOURNAL OF PLANT PHYSIOLOGY 2015; 172:120-7. [PMID: 25240792 DOI: 10.1016/j.jplph.2014.07.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/03/2014] [Accepted: 07/07/2014] [Indexed: 05/26/2023]
Abstract
The productivity and ecological distribution of freshwater plants can be controlled by the availability of inorganic carbon in water despite the existence of different mechanisms to ameliorate this, such as the ability to use bicarbonate. Here we took advantage of a short, natural gradient of CO2 concentration, against a background of very high and relatively constant concentration of bicarbonate, in a spring-fed river, to study the effect of variable concentration of CO2 on the ability of freshwater plants to use bicarbonate. Plants close to the source, where the concentration of CO2 was up to 24 times air equilibrium, were dominated by Berula erecta. pH-drift results and discrimination against (13)C were consistent with this and the other species being restricted to CO2 and unable to use the high concentration of bicarbonate. There was some indication from stable (13)C data that B. erecta may have had access to atmospheric CO2 at low water levels. In contrast, species downstream, where concentrations of CO2 were only about 5 times air-equilibrium were almost exclusively able to use bicarbonate, based on pH-drift results. Discrimination against (13)C was also consistent with bicarbonate being the main source of inorganic carbon for photosynthesis in these species. There was, therefore, a transect downstream from the source of increasing ability to use bicarbonate that closely matched the decreasing concentration of CO2. This was produced largely by altered species composition, but partly by phenotypic changes in individual species.
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Affiliation(s)
- S C Maberly
- Aix-Marseille Université CNRS, BIP UMR 7281, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France; Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK.
| | - S A Berthelot
- Aix-Marseille Université CNRS, BIP UMR 7281, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France
| | - A W Stott
- Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - B Gontero
- Aix-Marseille Université CNRS, BIP UMR 7281, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France
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Zhang Y, Yin L, Jiang HS, Li W, Gontero B, Maberly SC. Biochemical and biophysical CO2 concentrating mechanisms in two species of freshwater macrophyte within the genus Ottelia (Hydrocharitaceae). PHOTOSYNTHESIS RESEARCH 2014; 121:285-297. [PMID: 24203583 DOI: 10.1007/s11120-013-9950-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Accepted: 10/27/2013] [Indexed: 06/02/2023]
Abstract
Two freshwater macrophytes, Ottelia alismoides and O. acuminata, were grown at low (mean 5 μmol L(-1)) and high (mean 400 μmol L(-1)) CO2 concentrations under natural conditions. The ratio of PEPC to RuBisCO activity was 1.8 in O. acuminata in both treatments. In O. alismoides, this ratio was 2.8 and 5.9 when grown at high and low CO2, respectively, as a result of a twofold increase in PEPC activity. The activity of PPDK was similar to, and changed with, PEPC (1.9-fold change). The activity of the decarboxylating NADP-malic enzyme (ME) was very low in both species, while NAD-ME activity was high and increased with PEPC activity in O. alismoides. These results suggest that O. alismoides might perform a type of C4 metabolism with NAD-ME decarboxylation, despite lacking Kranz anatomy. The C4-activity was still present at high CO2 suggesting that it could be constitutive. O. alismoides at low CO2 showed diel acidity variation of up to 34 μequiv g(-1) FW indicating that it may also operate a form of crassulacean acid metabolism (CAM). pH-drift experiments showed that both species were able to use bicarbonate. In O. acuminata, the kinetics of carbon uptake were altered by CO2 growth conditions, unlike in O. alismoides. Thus, the two species appear to regulate their carbon concentrating mechanisms differently in response to changing CO2. O. alismoides is potentially using three different concentrating mechanisms. The Hydrocharitaceae have many species with evidence for C4, CAM or some other metabolism involving organic acids, and are worthy of further study.
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Affiliation(s)
- Yizhi Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
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Dou Y, Wang B, Chen L, Yin D. Alleviating versus stimulating effects of bicarbonate on the growth of Vallisneria natans under ammonia stress. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:5281-5288. [PMID: 23381797 DOI: 10.1007/s11356-013-1514-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 01/21/2013] [Indexed: 06/01/2023]
Abstract
Bicarbonate plays a crucial role in limiting the growth of submersed aquatic macrophytes in eutrophic lakes, and high ammonia is often toxic to macrophytes. In order to evaluate the combined effect of HCO3 (-) and total ammonia (i.e., the total of NH3 and NH4 (+)) on submersed macrophytes Vallisneria natans, the growth and physiological response of V. natans in the presence of HCO3 (-) and ammonia were studied. The results showed that with the increase of ammonia, morphological parameters of V. natans declined. In contrast, increased HCO3 (-) concentration stimulated the growth of V. natans, especially when the NH4 (+)-N/NO3 (-)-N ratio was 1:7. High ammonia concentration induced excess free amino acids (FAA) accumulation and soluble carbohydrates (SC) depletion in plant tissues. However, the elevated HCO3 (-) promoted the synthesis of SC and rendered the decrease of FAA/SC ratio. The results also suggested that HCO3 (-) could partially alleviate the stress of ammonia, as evidenced by the decrease of FAA/SC ratio and the growth enhancement of V. natans when the ammonia concentration was 0.58 mg L(-1). Given the fact that HCO3 (-) is probably the dominant available carbon source in most eutrophic lakes, the ability of V. natans to use HCO3 (-) for SC synthesis may explain the alleviating effect of HCO3 (-) on V. natans under ammonia stress.
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Affiliation(s)
- Yanyan Dou
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing, 210046, China
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Cowling SA. Did early land plants use carbon-concentrating mechanisms? TRENDS IN PLANT SCIENCE 2013; 18:120-124. [PMID: 23102567 DOI: 10.1016/j.tplants.2012.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 09/05/2012] [Accepted: 09/26/2012] [Indexed: 06/01/2023]
Abstract
Carbon-concentrating mechanisms (CCMs) in plants involve actively increasing CO2 concentrations near ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO). The assumption has been that terrestrial plants did not evolve CCMs for well over 300 million years, yet most marine plants probably evolved CCMs at the time when oxygenic photosynthesis first occurred in the Paleozoic. One primary reason for this assumption is that analysis of genetic mutations for phosphoenolpyruvate carboxylase (PEPc; an enzyme required for C4 and CAM photosynthesis) indicate a molecular age of no more than 65 Ma. Could the evolutionary response of both RuBisCO and PEPc to varying concentrations of atmospheric CO2 and O2 over geological time have obscured the real time when land plants first used PEPc during photosynthesis?
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Affiliation(s)
- Sharon A Cowling
- Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, Ontario, M5S 3B1, Canada.
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Klavsen SK, Madsen TV. Seasonal variation in crassulacean acid metabolism by the aquatic isoetid Littorella uniflora. PHOTOSYNTHESIS RESEARCH 2012; 112:163-173. [PMID: 22766959 DOI: 10.1007/s11120-012-9759-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/13/2012] [Indexed: 06/01/2023]
Abstract
The seasonal temperature acclimation in crassulacean acid metabolism (CAM) and photosynthetic performance were investigated in the aquatic isoetid, Littorella uniflora. Plants were collected monthly from January to September, and CAM capacity and photosynthesis rates were measured at 5, 10, 15, and 20 °C. Seasonal acclimation was observed for CAM (Q(10) range: 0.6-1.8), and CAM was optimised close to ambient temperature throughout the season. Thus, in winter acclimated L. uniflora, the short-term response to raised temperature resulted in a decline in CAM capacity. Even though the ambient CAM increased from winter to spring/summer, CAM was present in cold acclimated plants, thus indicating an ecophysiological role for CAM even in winter. Similar to CAM, seasonal acclimation was observed in the light and carbon-saturated photosynthesis (Q(10) values ranged from 1.4 to 2.3), and the photosynthetic capacity was generally higher during the winter at all temperatures, indicating compensatory investments in the photosynthetic apparatus. Thus, L. uniflora displayed seasonal temperature acclimation with respect to both CAM and photosynthesis. The estimated in situ contribution of CAM to the carbon budget in L. uniflora was independent of season and varied from 23 to 46 %. A positive correlation between photosynthetic capacity and CAM capacity (both measured in the lab at temperature close to ambient temperature) was found, and the ratio of CAM activity to photosynthetic capacity was higher in summer compared with winter plants. Overall, the results from the present study support the suggested role of CAM as a carbon conserving mechanism of importance for survival in a carbon-limited habitat.
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Affiliation(s)
- Signe Koch Klavsen
- Plant Biology, Department of Biological Sciences, Aarhus University, Ole Worms allé 1135, 8000 Aarhus C, Denmark.
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Zabaleta E, Martin MV, Braun HP. A basal carbon concentrating mechanism in plants? PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 187:97-104. [PMID: 22404837 DOI: 10.1016/j.plantsci.2012.02.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 02/01/2012] [Accepted: 02/02/2012] [Indexed: 05/14/2023]
Abstract
Many photosynthetic organisms have developed inorganic carbon (Ci) concentrating mechanisms (CCMs) that increase the CO₂ concentration within the vicinity of ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO). Several CCMs, such as four carbon (C4) and crassulacean acid metabolism (CAM), bicarbonate accumulation systems and capsular structures around RubisCO have been described in great detail. These systems are believed to have evolved several times as mechanisms that acclimate organisms to unfavourable growth conditions. Based on recent experimental evidence we propose the occurrence of another more general CCM system present in all plants. This basal CCM (bCCM) is supposed to be composed of mitochondrial carbonic anhydrases (a β-type carbonic anhydrase and the γ-type carbonic anhydrase domain of the mitochondrial NADH dehydrogenase complex) and probably further unknown components. The bCCM is proposed to reduce leakage of CO₂ from plant cells and allow efficient recycling of mitochondrial CO₂ for carbon fixation in chloroplasts.
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Affiliation(s)
- Eduardo Zabaleta
- Instituto de Investigaciones Biológicas IIB-CONICET-UNMdP, Funes 3250 3er nivel 7600 Mar del Plata, Argentina.
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Matsuda Y. Inorganic carbon utilization by aquatic photoautotrophs and potential usages of algal primary production. PHOTOSYNTHESIS RESEARCH 2011; 109:1-5. [PMID: 21909712 DOI: 10.1007/s11120-011-9683-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Accepted: 08/24/2011] [Indexed: 05/31/2023]
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