1
|
Ji N, Wang J, Huang W, Huang J, Cai Y, Sun S, Shen X, Liang Y. Transcriptome analysis of the harmful alga Heterosigma akashiwo under a 24-hour light-dark cycle. HARMFUL ALGAE 2024; 133:102601. [PMID: 38485440 DOI: 10.1016/j.hal.2024.102601] [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: 09/12/2023] [Revised: 01/29/2024] [Accepted: 02/05/2024] [Indexed: 03/19/2024]
Abstract
The photoperiod, which is defined as the period of time within a 24-hour time frame that light is available, is an important environmental regulator of several physiological processes in phytoplankton, including harmful bloom-forming phytoplankton. The ichthyotoxic raphidophyte Heterosigma akashiwo is a globally distributed bloom-forming phytoplankton. Despite extensive studies on the ecological impact of H. akashiwo, the influence of the photoperiod on crucial biological processes of this species remains unclear. In this study, gene expression in H. akashiwo was analyzed over a 24-hour light-dark (14:10) treatment period. Approximately 36 % of unigenes in H. akashiwo were differentially expressed during this 24-hour treatment period, which is indicative of their involvement in the response to light-dark variation. Notably, the number of differentially expressed genes exhibited an initial increase followed by a subsequent decrease as the sampling time progressed (T0 vs. other time points). Unigenes associated with photosynthesis and photoprotection reached their peak expression levels after 2-4 h of illumination (T12-T14). In contrast, the expression of unigenes associated with DNA replication peaked at the starting point of the dark period (T0). Furthermore, although several unigenes annotated to photoreceptors displayed potential diel periodicity, genes from various photoreceptor families (such as phytochrome and cryptochrome) showed unique expression patterns. Collectively, our findings offer novel perspectives on the response of H. akashiwo to the light-dark cycle, serving as a valuable resource for investigating the physiology and ecology of this species.
Collapse
Affiliation(s)
- Nanjing Ji
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China; Jiangsu Marine Resources Development Research Institute, Lianyungang 222005, China; CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
| | - Junyue Wang
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Wencong Huang
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Jinwang Huang
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Yuefeng Cai
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Song Sun
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Xin Shen
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Yue Liang
- Center of Deep Sea Research, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
| |
Collapse
|
2
|
Thangaraj S, Sun J. Ocean warming and acidification affect the transitional C:N:P ratio and macromolecular accumulation in the harmful raphidophyte Heterosigma akashiwo. Commun Biol 2023; 6:151. [PMID: 36747020 PMCID: PMC9902392 DOI: 10.1038/s42003-023-04524-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/24/2023] [Indexed: 02/08/2023] Open
Abstract
Despite an increase in ocean warming and acidification that is expected to increase the number of harmful algal species worldwide, the population of the raphidophyte Heterosigma akashiwo has been reported to be reduced. However, how this species physically and metabolically modifies transitional C:N:P ratio and macromolecule accumulation is unknown. Considering 1st, 10th, and 20th culture generations under present (low-temperature; low-carbon-dioxide [LTLC] 21 °C; pCO2 400 ppm) and future (high-temperature; high-carbon-dioxide [HTHC] 25 °C; pCO2 1000 ppm) ocean conditions, we examined transitional C:N:P ratio and macromolecule level changes and performed transcriptome sequencing. The results showed that compared to 1st generation cells, 20th generation cells under HTHC conditions showed a large decrease in carbon quota (QC: 34%), nitrogen quota (QN: 36%), and phosphorus quota (QP: 32%), which were reflected in an overall reduction in DNA and RNA quantity. Decreased activation of photosynthetic, carbon fixation and lipid metabolic pathways coincided with changes in photosynthetic efficiency, carbon concentration, and lipid accumulation after long-term (20th generation) exposure to HTHC conditions. We observed that these variations in internal metabolic pathways were caused by external changes in temperature, which activated the (Ca+) signaling pathway, and external changes in pCO2, which altered proton exchange pathways. Our results suggest that H. akashiwo in a temperate environment will undergo profound changes in C:N:P ratio and macromolecular properties, leading to programmed cell death, in the future.
Collapse
Affiliation(s)
- Satheeswaran Thangaraj
- Institute for Advanced Marine Research, China University of Geosciences, Guangzhou, China
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
- Department of Marine Science, Incheon National University, Incheon, South Korea
- Department of Physiology, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India
| | - Jun Sun
- Institute for Advanced Marine Research, China University of Geosciences, Guangzhou, China.
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China.
- Research Centre for Indian Ocean Ecosystem, Tianjin University of Science and Technology, Tianjin, China.
| |
Collapse
|
3
|
Balancing Damage via Non-Photochemical Quenching, Phenolic Compounds and Photorespiration in Ulva prolifera Induced by Low-Dose and Short-Term UV-B Radiation. Int J Mol Sci 2022; 23:ijms23052693. [PMID: 35269845 PMCID: PMC8911146 DOI: 10.3390/ijms23052693] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 11/25/2022] Open
Abstract
The Yellow Sea green tide (YSGT) is the world’s largest transregional macroalgal blooms, and the causative species Ulva prolifera (U. prolifera) suffers from ultraviolet-b radiation (UVBR) during the floating migration process. Previous study confirmed that U. prolifera displayed a wide variety of physiological responses characterized as acclimation to UVBR, while the response mechanisms against low-dose and short-term radiation (LDSTR) are not clear. A study with photosynthetically active radiation (PAR) and UVBR was designed: normal light (NL: 72 μmol photons m−2 s−1), NL+0.3 (UVBR: 0.3 W·m−2), and NL+1.6 (UVBR: 1.6 W·m−2). The results showed that high-dose UVBR inhibited photosynthesis in thalli, especially under long-term exposure, while a variety of physiological responses were observed under LDSTR. The inhibition of photosynthesis appeared to be ameliorated by the algae under LDSTR. Further analysis showed that U. prolifera achieved balancing damage by means of non-photochemical quenching (NPQ), accumulation of phenolic compounds coupled with the ASA-GSH cycle involved in the antioxidant process and enhanced photorespiratory metabolism under LDSTR. This study provides new insights into the balancing damage mechanisms of U. prolifera under LDSTR, enabling the thalli to adapt to the light conditions during the long duration and distance involved in floating migration.
Collapse
|
4
|
Münzner K, Gollnisch R, Rengefors K, Koreiviene J, Lindström ES. High Iron Requirements for Growth in the Nuisance Alga Gonyostomum semen (Raphidophyceae). JOURNAL OF PHYCOLOGY 2021; 57:1309-1322. [PMID: 33749827 DOI: 10.1111/jpy.13170] [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: 05/07/2020] [Revised: 02/26/2021] [Accepted: 03/03/2021] [Indexed: 06/12/2023]
Abstract
The bloom-forming freshwater alga Gonyostomum semen is associated with acidic, mesotrophic brown water lakes in boreal regions. However, researchers have been unable to conclusively link G. semen abundance and bloom formation to typical brown water lake traits, that is, high water color and DOC (dissolved organic carbon) concentrations. Iron is a main driver of water color in boreal lakes, and a recent study of lake monitoring data indicated a connection between lakes with high G. semen abundance and iron concentrations >200 µg · L-1 . Thus, iron may be the missing link in explaining G. semen abundance and growth dynamics. We experimentally assessed the effects of different iron concentrations above or below 200 µg · L-1 on the growth of G. semen batch monocultures. Iron concentrations <200 µg · L-1 limited G. semen growth, while iron concentrations >200 µg · L-1 did not. Moreover, the iron concentration of the medium required for growth was higher than for other common phytoplankton (Microcystis botrys and Chlamydomonas sp.) included in the experiment. These results indicate that G. semen requires high levels of iron in the lake environment. Consequently, this and previous findings using lake monitoring data support the hypothesis that high concentrations of iron favor the formation of high-density G. semen blooms in boreal brown water lakes. As lakes get browner in a changing climate, monitoring iron levels could be a potential tool to identify lakes at risk for G. semen blooms, especially among lakes that provide ecosystem services to society.
Collapse
Affiliation(s)
- Karla Münzner
- Department of Ecology and Genetics/Limnology, Uppsala University, Norbyvägen 18D, 75236, Uppsala, Sweden
| | - Raphael Gollnisch
- Aquatic Ecology, Department of Biology, Lund University, Sölvegatan 37, 22362, Lund, Sweden
| | - Karin Rengefors
- Aquatic Ecology, Department of Biology, Lund University, Sölvegatan 37, 22362, Lund, Sweden
| | - Judita Koreiviene
- Nature Research Centre, Akademijos Str. 2, Vilnius, LT-08412, Lithuania
| | - Eva S Lindström
- Department of Ecology and Genetics/Limnology, Uppsala University, Norbyvägen 18D, 75236, Uppsala, Sweden
| |
Collapse
|
5
|
Wu N, Tong M, Gou S, Zeng W, Xu Z, Jiang T. Hemolytic Activity in Relation to the Photosynthetic System in Chattonella marina and Chattonella ovata. Mar Drugs 2021; 19:336. [PMID: 34204792 PMCID: PMC8231601 DOI: 10.3390/md19060336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/07/2021] [Accepted: 06/09/2021] [Indexed: 11/16/2022] Open
Abstract
Chattonella species, C. marina and C. ovata, are harmful raphidophycean flagellates known to have hemolytic effects on many marine organisms and resulting in massive ecological damage worldwide. However, knowledge of the toxigenic mechanism of these ichthyotoxic flagellates is still limited. Light was reported to be responsible for the hemolytic activity (HA) of Chattonella species. Therefore, the response of photoprotective, photosynthetic accessory pigments, the photosystem II (PSII) electron transport chain, as well as HA were investigated in non-axenic C. marina and C. ovata cultures under variable environmental conditions (light, iron and addition of photosynthetic inhibitors). HA and hydrogen peroxide (H2O2) were quantified using erythrocytes and pHPA assay. Results confirmed that% HA of Chattonella was initiated by light, but was not always elicited during cell division. Exponential growth of C. marina and C. ovata under the light over 100 µmol m-2 s-1 or iron-sufficient conditions elicited high hemolytic activity. Inhibitors of PSII reduced the HA of C. marina, but had no effect on C. ovata. The toxicological response indicated that HA in Chattonella was not associated with the photoprotective system, i.e., xanthophyll cycle and regulation of reactive oxygen species, nor the PSII electron transport chain, but most likely occurred during energy transport through the light-harvesting antenna pigments. A positive, highly significant relationship between HA and chlorophyll (chl) biosynthesis pigments, especially chl c2 and chl a, in both species, indicated that hemolytic toxin may be generated during electron/energy transfer through the chl c2 biosynthesis pathway.
Collapse
Affiliation(s)
- Ni Wu
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, Research Center of Hydrobiology, Jinan University, Guangzhou 510632, China; (N.W.); (S.G.); (W.Z.)
- South China Sea Institute of Planning and Environmental Research, State Oceanic Administration, Guangzhou 510300, China
| | - Mengmeng Tong
- Ocean College, Zhejiang University, Zhoushan 316021, China;
| | - Siyu Gou
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, Research Center of Hydrobiology, Jinan University, Guangzhou 510632, China; (N.W.); (S.G.); (W.Z.)
| | - Weiji Zeng
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, Research Center of Hydrobiology, Jinan University, Guangzhou 510632, China; (N.W.); (S.G.); (W.Z.)
| | - Zhuoyun Xu
- Ocean College, Zhejiang University, Zhoushan 316021, China;
| | - Tianjiu Jiang
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, Research Center of Hydrobiology, Jinan University, Guangzhou 510632, China; (N.W.); (S.G.); (W.Z.)
| |
Collapse
|
6
|
Sun KM, Gao C, Zhang J, Tang X, Wang Z, Zhang X, Li Y. Rapid formation of antheraxanthin and zeaxanthin in seconds in microalgae and its relation to non-photochemical quenching. PHOTOSYNTHESIS RESEARCH 2020; 144:317-326. [PMID: 32323065 DOI: 10.1007/s11120-020-00739-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
The violaxanthin (V)-antheraxanthin (A)-zeaxanthin (Z) (VAZ) cycle was deemed a non-second-scale process of photoprotection in higher plants and microalgae, but the validity of this view has not been confirmed. To test this view, we explored responses of the VAZ cycle and the relationship between the VAZ cycle and non-photochemical quenching (NPQ) under highlight at second and minute scales in Heterosigma akashiwo and Platymonas sp. Both A and Z were generated in H. akashiwo during 15 s of light exposure, whereas only A rapidly accumulated within 15 s of exposure in Platymonas sp. The above results, together with a time-dependent sigmoidal relationship between the VAZ cycle (de-epoxidation state, A/Chl a, and Z/Chl a) and NPQ, proved that the VAZ cycle was a second-scale process related to NPQ. In addition, we found that not all NPQ was dependent on the VAZ cycle and suggested that NPQ model should be carefully modified due to the species-specific proportions of de-epoxidation-dependent NPQ.
Collapse
Affiliation(s)
- Kai-Ming Sun
- SOA Key Laboratory of Science and Engineering for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, Shandong, People's Republic of China
- Laboratory of Marine Ecology and Environmental Science, Pilot National Laboratory for Marine Science and Technology (Qingdao), 1 Wenhai Road, Aoshanwei, Jimo, Qingdao, 266237, Shandong, People's Republic of China
- College of Marine Life, Ocean University of China, 5 Rushan Road, Qingdao, 266003, Shandong, People's Republic of China
| | - Chunlei Gao
- SOA Key Laboratory of Science and Engineering for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, Shandong, People's Republic of China
| | - Jing Zhang
- Department of Biological and Chemical Engineering, Qingdao Technical College, 369 Qiantangjiang Road, Qingdao, 266555, Shandong, People's Republic of China
| | - Xuexi Tang
- College of Marine Life, Ocean University of China, 5 Rushan Road, Qingdao, 266003, Shandong, People's Republic of China
| | - Zongling Wang
- SOA Key Laboratory of Science and Engineering for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, Shandong, People's Republic of China
| | - Xuelei Zhang
- SOA Key Laboratory of Science and Engineering for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, Shandong, People's Republic of China
| | - Yan Li
- SOA Key Laboratory of Science and Engineering for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, Shandong, People's Republic of China.
| |
Collapse
|
7
|
Vidyarathna NK, Papke E, Coyne KJ, Cohen JH, Warner ME. Functional trait thermal acclimation differs across three species of mid-Atlantic harmful algae. HARMFUL ALGAE 2020; 94:101804. [PMID: 32414505 DOI: 10.1016/j.hal.2020.101804] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 03/05/2020] [Accepted: 04/04/2020] [Indexed: 06/11/2023]
Abstract
Characterizing the thermal niche of harmful algae is crucial for understanding and projecting the effects of future climate change on harmful algal blooms. The effects of 6 different temperatures (18-32 °C) on the growth, photophysiology, and toxicity were examined in the dinoflagellate Karlodinium veneficum, and the raphidophytes, Heterosigma akashiwo and Chattonella subsalsa from the Delaware Inland Bays (DIB). K. veneficum and H. akashiwo had skewed unimodal growth patterns, with temperature optima (Topt) at 28.6 and 27.3 °C respectively and an upper thermal niche limit of 32 °C. In contrast, C. subsalsa growth increased linearly with temperature, suggesting Topt and upper thermal boundaries >32 °C. K. veneficum photosystem II (PSII) photochemical efficiency remained stable across all temperatures, while H. akashiwo PSII efficiency declined at higher temperature and C. subsalsa was susceptible to low temperature (~18 °C) photoinactivation. Cell toxicity thermal response was species-specific such that K. veneficum toxicity increased with temperature above Topt. Raphidophyte toxicity peaked at 25-28 °C and was in close agreement with Topt for growth in H. akashiwo but below C. subsalsa maximal growth. The mode of toxicity was markedly different between the dinoflagellate and the raphidophytes such that K. veneficum had greater hemolytic activity while the raphidophytes had pronounced fish gill cell toxicity. These results and patterns of natural abundance for these algae in the DIB suggest that continued ocean warming may contribute to C. subsalsa bloom formation while possibly promoting highly toxic blooms of K. veneficum.
Collapse
Affiliation(s)
- Nayani K Vidyarathna
- School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, United States
| | - Erin Papke
- School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, United States
| | - Kathryn J Coyne
- School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, United States
| | - Jonathan H Cohen
- School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, United States
| | - Mark E Warner
- School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, United States.
| |
Collapse
|
8
|
Ji N, Lin L, Li L, Yu L, Zhang Y, Luo H, Li M, Shi X, Wang DZ, Lin S. Metatranscriptome analysis reveals environmental and diel regulation of a Heterosigma akashiwo
(raphidophyceae) bloom. Environ Microbiol 2018; 20:1078-1094. [DOI: 10.1111/1462-2920.14045] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 01/09/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Nanjing Ji
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
- Department of Marine Sciences; University of Connecticut; Groton CT 06340 USA
| | - Lingxiao Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Ling Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Liying Yu
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Yaqun Zhang
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Hao Luo
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Meizhen Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Xinguo Shi
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Da-Zhi Wang
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
- Department of Marine Sciences; University of Connecticut; Groton CT 06340 USA
| |
Collapse
|
9
|
Hidasi N, Belay A. Diurnal variation of various culture and biochemical parameters of Arthrospira platensis in large-scale outdoor raceway ponds. ALGAL RES 2018. [DOI: 10.1016/j.algal.2017.08.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
10
|
Bianco CM, Stewart JJ, Miller KR, Fitzgerald C, Coyne KJ. Light intensity impacts the production of biofuel intermediates in Heterosigma akashiwo growing on simulated flue gas containing carbon dioxide and nitric oxide. BIORESOURCE TECHNOLOGY 2016; 219:246-251. [PMID: 27494106 DOI: 10.1016/j.biortech.2016.07.119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/26/2016] [Accepted: 07/27/2016] [Indexed: 05/06/2023]
Abstract
As a potential biofuel feedstock, the marine microalga, Heterosigma akashiwo, accumulates significant lipids, is capable of long-term growth in outdoor photobioreactors, and is an excellent candidate for the bioremediation of industrial emissions. Here, we evaluated resource partitioning in H. akashiwo growing on a CO2 and NO gas mixture under three light intensities: 160, 560, or 1200μmolquantam(-2)s(-1). Light levels had no effect on growth; however, cultures in high light accumulated 2.3-fold more carbohydrates and 17% fewer lipids. Light levels did not affect the percentage of saturated fatty acids, but mono-unsaturates increased by 6% and poly-unsaturates decreased by 12% in high light. The fatty acid profiles reported here suggest that H. akashiwo is a good candidate for the production of neutral lipids for biodiesel and also omega-3 fatty acids, and that the quality of biodiesel acquired from feedstocks grown under fluctuating light conditions would be relatively stable.
Collapse
Affiliation(s)
- Colleen M Bianco
- University of Delaware, School of Marine Science and Policy, Lewes, DE 19958, USA
| | - Jennifer J Stewart
- University of Delaware, School of Marine Science and Policy, Lewes, DE 19958, USA.
| | | | | | - Kathryn J Coyne
- University of Delaware, School of Marine Science and Policy, Lewes, DE 19958, USA
| |
Collapse
|
11
|
Comparing the diel vertical migration of Karlodinium veneficum (dinophyceae) and Chattonella subsalsa (Raphidophyceae): PSII photochemistry, circadian control, and carbon assimilation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 143:107-19. [PMID: 25618815 DOI: 10.1016/j.jphotobiol.2014.12.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 12/06/2014] [Accepted: 12/18/2014] [Indexed: 11/23/2022]
Abstract
Diel vertical migration (DVM) is thought to provide an adaptive advantage to some phytoplankton, and may help determine the ecological niche of certain harmful algae. Here we separately compared DVM patterns between two species of harmful algae isolated from the Delaware Inland Bays, Karlodinium veneficum and Chattonella subsalsa, in laboratory columns. We interpreted the DVM patterns of each species with Photosystem II (PSII) photochemistry, rates of carbon assimilation, and specific growth rates. Each species migrated differently, wherein K. veneficum migrated closer to the surface each day with high population synchrony, while C. subsalsa migrated near to the surface from the first day of measurements with low population synchrony. Both species appeared to downregulate PSII in high light at the surface, but by different mechanisms. C. subsalsa grew slower than K. veneficum in low light intensities (≈bottom of columns), and exhibited maximal rates of C-assimilation (Pmax) at surface light intensities, suggesting this species may prefer high light, potentially explaining this species' rapid surface migration. Contrastingly, K. veneficum showed declines in carbon assimilation at surface light intensities, and exhibited a smaller reduction in growth at low (bottom) light intensities (compared to C. subsalsa), suggesting that this species' step-wise migration was photoacclimative and determined daily migration depth. DVM was found to be under circadian control in C. subsalsa, but not in K. veneficum. However, there was little evidence for circadian regulation of PSII photochemistry in either species. Migration conformed to each species' physiology, and the results contribute to our understanding each alga's realized environmental niche.
Collapse
|
12
|
Goss R, Lepetit B. Biodiversity of NPQ. JOURNAL OF PLANT PHYSIOLOGY 2015; 172:13-32. [PMID: 24854581 DOI: 10.1016/j.jplph.2014.03.004] [Citation(s) in RCA: 241] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 05/21/2023]
Abstract
In their natural environment plants and algae are exposed to rapidly changing light conditions and light intensities. Illumination with high light intensities has the potential to overexcite the photosynthetic pigments and the electron transport chain and thus induce the production of toxic reactive oxygen species (ROS). To prevent damage by the action of ROS, plants and algae have developed a multitude of photoprotection mechanisms. One of the most important protection mechanisms is the dissipation of excessive excitation energy as heat in the light-harvesting complexes of the photosystems. This process requires a structural change of the photosynthetic antenna complexes that are normally optimized with regard to efficient light-harvesting. Enhanced heat dissipation in the antenna systems is accompanied by a strong quenching of the chlorophyll a fluorescence and has thus been termed non-photochemical quenching of chlorophyll a fluorescence, NPQ. The general importance of NPQ for the photoprotection of plants and algae is documented by its wide distribution in the plant kingdom. In the present review we will summarize the present day knowledge about NPQ in higher plants and different algal groups with a special focus on the molecular mechanisms that lead to the structural rearrangements of the antenna complexes and enhanced heat dissipation. We will present the newest models for NPQ in higher plants and diatoms and will compare the features of NPQ in different algae with those of NPQ in higher plants. In addition, we will briefly address evolutionary aspects of NPQ, i.e. how the requirements of NPQ have changed during the transition of plants from the aquatic habitat to the land environment. We will conclude with a presentation of open questions regarding the mechanistic basis of NPQ and suggestions for future experiments that may serve to obtain this missing information.
Collapse
Affiliation(s)
- Reimund Goss
- Institut für Biologie, Universität Leipzig, Johannisallee 21-23, D-04103 Leipzig, Germany.
| | - Bernard Lepetit
- Institut für Biologie, Universität Konstanz, Universitätsstrasse 10, D-78457 Konstanz, Germany
| |
Collapse
|