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Bui QTN, Pradhan B, Kim HS, Ki JS. Environmental Factors Modulate Saxitoxins (STXs) Production in Toxic Dinoflagellate Alexandrium: An Updated Review of STXs and Synthesis Gene Aspects. Toxins (Basel) 2024; 16:210. [PMID: 38787062 PMCID: PMC11125744 DOI: 10.3390/toxins16050210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/23/2024] [Accepted: 04/28/2024] [Indexed: 05/25/2024] Open
Abstract
The marine dinoflagellate Alexandrium is known to form harmful algal blooms (HABs) and produces saxitoxin (STX) and its derivatives (STXs) that cause paralytic shellfish poisoning (PSP) in humans. Cell growth and cellular metabolism are affected by environmental conditions, including nutrients, temperature, light, and the salinity of aquatic systems. Abiotic factors not only engage in photosynthesis, but also modulate the production of toxic secondary metabolites, such as STXs, in dinoflagellates. STXs production is influenced by a variety of abiotic factors; however, the relationship between the regulation of these abiotic variables and STXs accumulation seems not to be consistent, and sometimes it is controversial. Few studies have suggested that abiotic factors may influence toxicity and STXs-biosynthesis gene (sxt) regulation in toxic Alexandrium, particularly in A. catenella, A. minutum, and A. pacificum. Hence, in this review, we focused on STXs production in toxic Alexandrium with respect to the major abiotic factors, such as temperature, salinity, nutrients, and light intensity. This review informs future research on more sxt genes involved in STXs production in relation to the abiotic factors in toxic dinoflagellates.
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Affiliation(s)
- Quynh Thi Nhu Bui
- Department of Life Science, Sangmyung University, Seoul 03016, Republic of Korea; (Q.T.N.B.); (H.-S.K.)
| | - Biswajita Pradhan
- Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea;
- Department of Botany, Model Degree College, Rayagada 765017, Odisha, India
| | - Han-Sol Kim
- Department of Life Science, Sangmyung University, Seoul 03016, Republic of Korea; (Q.T.N.B.); (H.-S.K.)
| | - Jang-Seu Ki
- Department of Life Science, Sangmyung University, Seoul 03016, Republic of Korea; (Q.T.N.B.); (H.-S.K.)
- Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea;
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2
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Rengefors K, Annenkova N, Wallenius J, Svensson M, Kremp A, Ahrén D. Population genomic analyses reveal that salinity and geographic isolation drive diversification in a free-living protist. Sci Rep 2024; 14:4986. [PMID: 38424140 PMCID: PMC10904836 DOI: 10.1038/s41598-024-55362-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/22/2024] [Indexed: 03/02/2024] Open
Abstract
Protists make up the vast diversity of eukaryotic life and play a critical role in biogeochemical cycling and in food webs. Because of their small size, cryptic life cycles, and large population sizes, our understanding of speciation in these organisms is very limited. We performed population genomic analyses on 153 strains isolated from eight populations of the recently radiated dinoflagellate genus Apocalathium, to explore the drivers and mechanisms of speciation processes. Species of this genus inhabit both freshwater and saline habitats, lakes and seas, and are found in cold temperate environments across the world. RAD sequencing analyses revealed that the populations were overall highly differentiated, but morphological similarity was not congruent with genetic similarity. While geographic isolation was to some extent coupled to genetic distance, this pattern was not consistent. Instead, we found evidence that the environment, specifically salinity, is a major factor in driving ecological speciation in Apocalathium. While saline populations were unique in loci coupled to genes involved in osmoregulation, freshwater populations appear to lack these. Our study highlights that adaptation to freshwater through loss of osmoregulatory genes may be an important speciation mechanism in free-living aquatic protists.
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Affiliation(s)
- Karin Rengefors
- Department of Biology, Lund University, 223 62, Lund, Sweden.
| | - Nataliia Annenkova
- Department of Biology, Lund University, 223 62, Lund, Sweden
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Avenue 4, St. Petersburg, 194064, Russia
| | - Joel Wallenius
- Department of Biology, Lund University, 223 62, Lund, Sweden
- Department of Clinical Sciences, Faculty of Medicine, Lund University, 223 62, Lund, Sweden
| | - Marie Svensson
- Department of Biology, Lund University, 223 62, Lund, Sweden
| | - Anke Kremp
- Biology Department, Leibniz Institute for Baltic Sea Research Warnemuende, Seestr. 15, 18119, Rostock, Germany
| | - Dag Ahrén
- Department of Biology, Lund University, 223 62, Lund, Sweden
- National Bioinformatics Infrastructure Sweden (NBIS), SciLifeLab, Department of Biology, Lund University, Lund, Sweden
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3
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Huang D, Cheng CQ, Qiu JB, Huang Y, Zhang HY, Xu ZH, Wu SW, Huang YT, Chen J, Zou LG, Yang WD, Zheng XF, Li HY, Li DW. Mechanistic insights into the effects of diuron exposure on Alexandrium pacificum. WATER RESEARCH 2024; 250:120987. [PMID: 38113594 DOI: 10.1016/j.watres.2023.120987] [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: 09/20/2023] [Revised: 12/03/2023] [Accepted: 12/06/2023] [Indexed: 12/21/2023]
Abstract
Diuron (N-(3,4-dichlorophenyl)-N,N‑dimethylurea, DCMU), a ureic herbicide, is extensively used in agriculture to boost crop productivity; however, its extensive application culminates in notable environmental pollution, especially in aquatic habitats. Therefore, the present study investigated the effect of diuron on the dinoflagellate Alexandrium pacificum, which is known to induce harmful algal blooms (HAB), and its potential to biodegrade DCMU. Following a four-day DCMU exposure, our results revealed that A. pacificum proficiently assimilated DCMU at concentrations of 0.05 mg/L and 0.1 mg/L in seawater, attaining a complete reduction (100 % efficiency) after 96 h for both concentrations. Moreover, evaluations of paralytic shellfish toxins content indicated that cells subjected to higher DCMU concentrations (0.1 mg/L) exhibited reductions of 73.4 %, 86.7 %, and 75 % in GTX1, GTX4, and NEO, respectively. Exposure to DCMU led to a notable decrease in A. pacificum's photosynthetic efficacy, accompanied by increased levels of reactive oxygen species (ROS) and suppressed cell growth, with a growth inhibition rate of 41.1 % at 72 h. Proteomic investigations pinpointed the diminished expression levels of specific proteins like SxtV and SxtW, linked to paralytic shellfish toxins (PSTs) synthesis, as well as key proteins associated with Photosystem II, namely PsbA, PsbD, PsbO, and PsbU. Conversely, proteins central to the cysteine biosynthesis pathways exhibited enhanced expression. In summary, our results preliminarily resolved the molecular mechanisms underlying the response of A. pacificum to DCMU and revealed that DCMU affected the synthesis of PSTs. Meanwhile, our data suggested that A. pacificum has great potential in scavenging DCMU.
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Affiliation(s)
- Dan Huang
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Cai-Qin Cheng
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Jiang-Bing Qiu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yun Huang
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Hao-Yun Zhang
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Zhen-Hao Xu
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Si-Wei Wu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Yi-Tong Huang
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Jian Chen
- State Key Laboratory of Medical Vector Surveillance, Zhuhai International Travel Healthcare Center, Zhuhai, Guangdong 519020, China
| | - Li-Gong Zou
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Wei-Dong Yang
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Xiao-Fei Zheng
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Hong-Ye Li
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China
| | - Da-Wei Li
- Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou 510630, China.
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Dkhar DS, Kumari R, Mahapatra S, Divya, Kumar R, Tripathi T, Chandra P. Antibody-receptor bioengineering and its implications in designing bioelectronic devices. Int J Biol Macromol 2022; 218:225-242. [PMID: 35870626 DOI: 10.1016/j.ijbiomac.2022.07.109] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 11/16/2022]
Abstract
Antibodies play a crucial role in the defense mechanism countering pathogens or foreign antigens in eukaryotes. Its potential as an analytical and diagnostic tool has been exploited for over a century. It forms immunocomplexes with a specific antigen, which is the basis of immunoassays and aids in developing potent biosensors. Antibody-based sensors allow for the quick and accurate detection of various analytes. Though classical antibodies have prolonged been used as bioreceptors in biosensors fabrication due to their increased fragility, they have been engineered into more stable fragments with increased exposure of their antigen-binding sites in the recent era. In biosensing, the formats constructed by antibody engineering can enhance the signal since the resistance offered by a conventional antibody is much more than these fragments. Hence, signal amplification can be observed when antibody fragments are utilized as bioreceptors instead of full-length antibodies. We present the first systematic review on engineered antibodies as bioreceptors with the description of their engineering methods. The detection of various target analytes, including small molecules, macromolecules, and cells using antibody-based biosensors, has been discussed. A comparison of the classical polyclonal, monoclonal, and engineered antibodies as bioreceptors to construct highly accurate, sensitive, and specific sensors is also discussed.
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Affiliation(s)
- Daphika S Dkhar
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India
| | - Rohini Kumari
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India
| | - Supratim Mahapatra
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India
| | - Divya
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India
| | - Rahul Kumar
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India
| | - Timir Tripathi
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India; Regional Director's Office, Indira Gandhi National Open University (IGNOU), Regional Centre Kohima, Kenuozou, Kohima 797001, India.
| | - Pranjal Chandra
- Laboratory of Bio-Physio Sensors and Nano-bioengineering, School of Biochemical Engineering, Indian Institute of Technology (BHU) Varanasi, Uttar Pradesh 221005, India.
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5
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Lian Z, Li F, He X, Chen J, Yu RC. Rising CO 2 will increase toxicity of marine dinoflagellate Alexandrium minutum. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128627. [PMID: 35359114 DOI: 10.1016/j.jhazmat.2022.128627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
Ocean acidification caused by increasing emission of carbon dioxide (CO2) is expected to have profound impacts on marine ecological processes, including the formation and evolution of harmful algal blooms (HABs). We designed a set of experiments in the laboratory to examine the effects of increasing CO2 on the growth and toxicity of a toxic dinoflagellate Alexandrium minutum producing paralytic shellfish toxins (PSTs). It was found that high levels of CO2 (800 and 1200 ppm) significantly promoted the growth of A. minutum compared to the group (400 ppm) representing the current CO2 level. The total yields of PSTs by A. minutum, including both intracellular and extracellular toxins, were significantly enhanced, probably due to the induction of core enzyme activity and key amino acids synthesis for PST production. More interestingly, high level of CO2 promoted the transformation from gonyautoxin2&3 to gonyautoxin1&4 and depressed the release of PSTs from inside to outside of the cells. All these processes collectively led to an apparent increase of A. minutum toxicity. Our study demonstrated that rising CO2 would increase the risk of toxic A. minutum based on the comprehensive analyses of different processes including algal growth and toxin synthesis, transformation and release.
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Affiliation(s)
- Ziru Lian
- Marine College, Shandong University, Weihai 264209, PR China.
| | - Fang Li
- Marine College, Shandong University, Weihai 264209, PR China; Marine Bioresource and Environment Research Center, Key Laboratory of Marine Eco-Environmental Science and Technology, The First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China
| | - Xiuping He
- Marine Bioresource and Environment Research Center, Key Laboratory of Marine Eco-Environmental Science and Technology, The First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China
| | - Junhui Chen
- Marine Bioresource and Environment Research Center, Key Laboratory of Marine Eco-Environmental Science and Technology, The First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, PR China
| | - Ren-Cheng Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
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6
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Li C, Crack JC, Newton‐Payne S, Murphy ARJ, Chen X, Pinchbeck BJ, Zhou S, Williams BT, Peng M, Zhang X, Chen Y, Le Brun NE, Todd JD, Zhang Y. Mechanistic insights into the key marine dimethylsulfoniopropionate synthesis enzyme DsyB/DSYB. MLIFE 2022; 1:114-130. [PMID: 38817677 PMCID: PMC10989797 DOI: 10.1002/mlf2.12030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 06/01/2024]
Abstract
Marine algae and bacteria produce approximately eight billion tonnes of the organosulfur molecule dimethylsulfoniopropionate (DMSP) in Earth's surface oceans annually. DMSP is an antistress compound and, once released into the environment, a major nutrient, signaling molecule, and source of climate-active gases. The methionine transamination pathway for DMSP synthesis is used by most known DMSP-producing algae and bacteria. The S-directed S-adenosylmethionine (SAM)-dependent 4-methylthio-2-hydroxybutyrate (MTHB) S-methyltransferase, encoded by the dsyB/DSYB gene, is the key enzyme of this pathway, generating S-adenosylhomocysteine (SAH) and 4-dimethylsulfonio-2-hydroxybutyrate (DMSHB). DsyB/DSYB, present in most haptophyte and dinoflagellate algae with the highest known intracellular DMSP concentrations, is shown to be far more abundant and transcribed in marine environments than any other known S-methyltransferase gene in DMSP synthesis pathways. Furthermore, we demonstrate in vitro activity of the bacterial DsyB enzyme from Nisaea denitrificans and provide its crystal structure in complex with SAM and SAH-MTHB, which together provide the first important mechanistic insights into a DMSP synthesis enzyme. Structural and mutational analyses imply that DsyB adopts a proximity and desolvation mechanism for the methyl transfer reaction. Sequence analysis suggests that this mechanism may be common to all bacterial DsyB enzymes and also, importantly, eukaryotic DSYB enzymes from e.g., algae that are the major DMSP producers in Earth's surface oceans.
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Affiliation(s)
- Chun‐Yang Li
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life SciencesOcean University of ChinaQingdaoChina
- State Key Laboratory of Microbial TechnologyMarine Biotechnology Research Center, Shandong UniversityQingdaoChina
- Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdaoShandongChina
| | - Jason C. Crack
- School of Chemistry, Centre for Molecular and Structural BiochemistryUniversity of East Anglia, Norwich Research ParkNorwichUK
| | | | | | - Xiu‐Lan Chen
- State Key Laboratory of Microbial TechnologyMarine Biotechnology Research Center, Shandong UniversityQingdaoChina
- Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdaoShandongChina
| | | | - Shun Zhou
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life SciencesOcean University of ChinaQingdaoChina
- School of Biological SciencesUniversity of East AngliaNorwichUK
| | | | - Ming Peng
- State Key Laboratory of Microbial TechnologyMarine Biotechnology Research Center, Shandong UniversityQingdaoChina
| | - Xiao‐Hua Zhang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life SciencesOcean University of ChinaQingdaoChina
| | - Yin Chen
- School of Life SciencesUniversity of WarwickCoventryUK
| | - Nick E. Le Brun
- School of Chemistry, Centre for Molecular and Structural BiochemistryUniversity of East Anglia, Norwich Research ParkNorwichUK
| | - Jonathan D. Todd
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life SciencesOcean University of ChinaQingdaoChina
- School of Biological SciencesUniversity of East AngliaNorwichUK
| | - Yu‐Zhong Zhang
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, College of Marine Life SciencesOcean University of ChinaQingdaoChina
- State Key Laboratory of Microbial TechnologyMarine Biotechnology Research Center, Shandong UniversityQingdaoChina
- Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdaoShandongChina
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7
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Shaw DK, Sekar J, Ramalingam PV. Recent insights into oceanic dimethylsulfoniopropionate biosynthesis and catabolism. Environ Microbiol 2022; 24:2669-2700. [PMID: 35611751 DOI: 10.1111/1462-2920.16045] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 11/29/2022]
Abstract
Dimethylsulfoniopropionate (DMSP), a globally important organosulfur compound is produced in prodigious amounts (2.0 Pg sulfur) annually in the marine environment by phytoplankton, macroalgae, heterotrophic bacteria, some corals and certain higher plants. It is an important marine osmolyte and a major precursor molecule for the production of climate-active volatile gas dimethyl sulfide (DMS). DMSP synthesis take place via three pathways: a transamination 'pathway-' in some marine bacteria and algae, a Met-methylation 'pathway-' in angiosperms and bacteria and a decarboxylation 'pathway-' in the dinoflagellate, Crypthecodinium. The enzymes DSYB and TpMMT are involved in the DMSP biosynthesis in eukaryotes while marine heterotrophic bacteria engage key enzymes such as DsyB and MmtN. Several marine bacterial communities import DMSP and degrade it via cleavage or demethylation pathways or oxidation pathway, thereby generating DMS, methanethiol, and dimethylsulfoxonium propionate, respectively. DMSP is cleaved through diverse DMSP lyase enzymes in bacteria and via Alma1 enzyme in phytoplankton. The demethylation pathway involves four different enzymes, namely DmdA, DmdB, DmdC and DmdD/AcuH. However, enzymes involved in the oxidation pathway have not been yet identified. We reviewed the recent advances on the synthesis and catabolism of DMSP and enzymes that are involved in these processes.
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Affiliation(s)
- Deepak Kumar Shaw
- Microbiology Lab, Department of Biotechnology, M. S. Swaminathan Research Foundation, Taramani, Chennai, 600113, Tamil Nadu, India
| | - Jegan Sekar
- Microbiology Lab, Department of Biotechnology, M. S. Swaminathan Research Foundation, Taramani, Chennai, 600113, Tamil Nadu, India
| | - Prabavathy Vaiyapuri Ramalingam
- Microbiology Lab, Department of Biotechnology, M. S. Swaminathan Research Foundation, Taramani, Chennai, 600113, Tamil Nadu, India
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Zaiko A, von Ammon U, Stuart J, Smith KF, Yao R, Welsh M, Pochon X, Bowers HA. Assessing the performance and efficiency of environmental
DNA
/
RNA
capture methodologies under controlled experimental conditions. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anastasija Zaiko
- Cawthron Institute Private Bag 2, Nelson 7042 New Zealand
- Institute of Marine Science University of Auckland, Private Bag 92019, Auckland 1142 New Zealand
| | - Ulla von Ammon
- Cawthron Institute Private Bag 2, Nelson 7042 New Zealand
| | - Jacqui Stuart
- Cawthron Institute Private Bag 2, Nelson 7042 New Zealand
| | - Kirsty F. Smith
- Cawthron Institute Private Bag 2, Nelson 7042 New Zealand
- School of Biological Sciences University of Auckland, Private Bag 92019, Auckland 1142 New Zealand
| | - Richard Yao
- Scion (NZ Forest Research Institute), Te Papa Tipu Innovation Park, Titokorangi Drive, Whakarewarewa Rotorua 3010 New Zealand
| | - Melissa Welsh
- Scion (NZ Forest Research Institute), P.O. Box 29237 Christchurch 8540 New Zealand
| | - Xavier Pochon
- Cawthron Institute Private Bag 2, Nelson 7042 New Zealand
- Institute of Marine Science University of Auckland, Private Bag 92019, Auckland 1142 New Zealand
| | - Holly A. Bowers
- Moss Landing Marine Laboratories San Jose State University Moss Landing, California, 95039 USA
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9
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Jean N, Perié L, Dumont E, Bertheau L, Balliau T, Caruana AMN, Amzil Z, Laabir M, Masseret E. Metal stresses modify soluble proteomes and toxin profiles in two Mediterranean strains of the distributed dinoflagellate Alexandrium pacificum. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 818:151680. [PMID: 34793790 DOI: 10.1016/j.scitotenv.2021.151680] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 10/25/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
HABs involving Alexandrium pacificum have been reported in metal-contaminated ecosystems, suggesting that this distributed species adapts to and/or can tolerate the effects of metals. Modifications in soluble proteomes and PST contents were characterized in two Mediterranean A. pacificum strains exposed to mono- or polymetallic stresses (zinc, lead, copper, cadmium). These strains were isolated from two anthropized locations: Santa Giusta Lagoon (Italy, SG C10-3) and the Tarragona seaport (Spain, TAR C5-4F). In both strains, metals primarily downregulated key photosynthesis proteins. Metals also upregulated other proteins involved in photosynthesis (PCP in both strains), the oxidative stress response (HSP 60, proteasome and SOD in SG C10-3; HSP 70 in TAR C5-4F), energy metabolism (AdK in TAR C5-4F), neoglucogenesis/glycolysis (GAPDH and PEP synthase in SG C10-3) and protein modification (PP in TAR C5-4F). These proteins, possibly involved in adaptive proteomic responses, may explain the development of these A. pacificum strains in metal-contaminated ecosystems. The two strains showed different proteomic responses to metals, with SG C10-3 upregulating more proteins, particularly PCP. Among the PSTs, regardless of the metal and the strain studied, C2 and GTX4 predominated, followed by GTX5. Under the polymetallic cocktail, (i) total PSTs, C2 and GTX4 reached the highest levels in SG C10-3 only, and (ii) total PSTs, C2, GTX5 and neoSTX were higher in SG C10-3 than in TAR C5-4F, whereas in SG C10-3 under copper stress, total PSTs, GTX5, GTX1 and C1 were higher than in the controls, revealing variability in PST biosynthesis between the two strains. Total PSTs, C2, GTX4 and GTX1 showed significant positive correlations with PCP, indicating that PST production may be positively related to photosynthesis. Our results showed that the A. pacificum strains adapt their proteomic and physiological responses to metals, which may contribute to their ecological success in highly anthropized areas.
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Affiliation(s)
- Natacha Jean
- Université de Toulon, Aix Marseille Univ, CNRS, IRD, MIO, Toulon, France.
| | - Luce Perié
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, New York University, 30(th) St., New York, NY 10016, USA
| | - Estelle Dumont
- UMR_MD1, Aix-Marseille Univ, U-1261-INSERM, SSA, IRBA, MCT, Marseille, France
| | - Lucie Bertheau
- UMR PAM A 02.102 Procédés Alimentaires et Microbiologiques, Université de Bourgogne Franche-Comté, AgroSup Dijon, esplanade Erasme, 21 000 Dijon, France
| | - Thierry Balliau
- PAPPSO-GQE-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91 190 Gif-sur-Yvette, France
| | - Amandine M N Caruana
- IFREMER, Phycotoxin Laboratory, rue de l'île d'Yeu, BP 21105, 44 311 Nantes, France
| | - Zouher Amzil
- IFREMER, Phycotoxin Laboratory, rue de l'île d'Yeu, BP 21105, 44 311 Nantes, France
| | - Mohamed Laabir
- Marbec, Univ Montpellier, IRD, Ifremer, CNRS, Montpellier, France
| | - Estelle Masseret
- Marbec, Univ Montpellier, IRD, Ifremer, CNRS, Montpellier, France
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10
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Wang H, Kim H, Park H, Ki JS. Temperature influences the content and biosynthesis gene expression of saxitoxins (STXs) in the toxigenic dinoflagellate Alexandrium pacificum. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149801. [PMID: 34454155 DOI: 10.1016/j.scitotenv.2021.149801] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Temperature may affect the production of saxitoxin (STX) and its derivatives (STXs); however, this is still controversial. Further, STX-biosynthesis gene regulation and the relation of its toxicity with temperature are not clearly understood. In the present study, we evaluated the effects of different temperatures (12 °C, 16 °C, and 20 °C) on the growth, toxin profiles, and expression of two core STX-biosynthesis genes, sxtA and sxtG, in the toxic dinoflagellate Alexandrium pacificum Alex05, isolated from Korean coasts. We found that temperature significantly affected cell growth, with maximum growth recorded at 16 °C, followed by 20 °C and 12 °C. HPLC analysis revealed mostly 12 of STXs from the tested cultures. Interestingly, the contents of STXs increased in the cells cultured at 16 °C and exposed to cold stress, compared to the 20 °C culture and heat stress; however, toxin components were much more diverse under heat stress. These toxin profiles generally matched with the sxtA and sxtG expression levels. Incubation at lower temperatures (12 °C and 16 °C) and exposure to cold stress increased sxtA and sxtG expressions in the cells, whereas heat stress showed little change or downregulated the transcription of both genes. Principal component analysis (PCA) showed low correlation between STXs eq and expressional levels of sxtA and sxtG in heat-stressed cells. These results suggest that temperature might be a crucial factor affecting the level and biosynthesis of STXs in marine toxic dinoflagellates.
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Affiliation(s)
- Hui Wang
- Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea; Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China
| | - Hansol Kim
- Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea
| | - Hyunjun Park
- Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea
| | - Jang-Seu Ki
- Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea.
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Geffroy S, Lechat MM, Le Gac M, Rovillon GA, Marie D, Bigeard E, Malo F, Amzil Z, Guillou L, Caruana AMN. From the sxtA4 Gene to Saxitoxin Production: What Controls the Variability Among Alexandrium minutum and Alexandrium pacificum Strains? Front Microbiol 2021; 12:613199. [PMID: 33717003 PMCID: PMC7944994 DOI: 10.3389/fmicb.2021.613199] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 02/03/2021] [Indexed: 12/22/2022] Open
Abstract
Paralytic shellfish poisoning (PSP) is a human foodborne syndrome caused by the consumption of shellfish that accumulate paralytic shellfish toxins (PSTs, saxitoxin group). In PST-producing dinoflagellates such as Alexandrium spp., toxin synthesis is encoded in the nuclear genome via a gene cluster (sxt). Toxin production is supposedly associated with the presence of a 4th domain in the sxtA gene (sxtA4), one of the core genes of the PST gene cluster. It is postulated that gene expression in dinoflagellates is partially constitutive, with both transcriptional and post-transcriptional processes potentially co-occurring. Therefore, gene structure and expression mode are two important features to explore in order to fully understand toxin production processes in dinoflagellates. In this study, we determined the intracellular toxin contents of twenty European Alexandrium minutum and Alexandrium pacificum strains that we compared with their genome size and sxtA4 gene copy numbers. We observed a significant correlation between the sxtA4 gene copy number and toxin content, as well as a moderate positive correlation between the sxtA4 gene copy number and genome size. The 18 toxic strains had several sxtA4 gene copies (9-187), whereas only one copy was found in the two observed non-toxin producing strains. Exploration of allelic frequencies and expression of sxtA4 mRNA in 11 A. minutum strains showed both a differential expression and specific allelic forms in the non-toxic strains compared with the toxic ones. Also, the toxic strains exhibited a polymorphic sxtA4 mRNA sequence between strains and between gene copies within strains. Finally, our study supported the hypothesis of a genetic determinism of toxin synthesis (i.e., the existence of several genetic isoforms of the sxtA4 gene and their copy numbers), and was also consistent with the hypothesis that constitutive gene expression and moderation by transcriptional and post-transcriptional regulation mechanisms are the cause of the observed variability in the production of toxins by A. minutum.
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Affiliation(s)
| | | | | | | | - Dominique Marie
- Sorbonne Université, CNRS, UMR 7144 Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
| | - Estelle Bigeard
- Sorbonne Université, CNRS, UMR 7144 Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
| | | | | | - Laure Guillou
- Sorbonne Université, CNRS, UMR 7144 Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
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