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Yao X, Song Z, Yang G, Yonas MW, Hamilton PB, Nwankwegu AS, Adeyeye O, Huang W, Luo X, Hassaan AM, Haffner GD, Zhang L. How water stability relates with timing, size, and community successions of harmful algal blooms: A case study in the Three Gorges Reservoir. MARINE POLLUTION BULLETIN 2024; 206:116781. [PMID: 39096867 DOI: 10.1016/j.marpolbul.2024.116781] [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: 05/17/2024] [Revised: 07/23/2024] [Accepted: 07/23/2024] [Indexed: 08/05/2024]
Abstract
Effective management of Harmful Algal Blooms (HABs) requires understanding factors influencing their occurrence. This study explores these dynamics in the Pengxi River, a tributary of the Three Gorges Reservoir, focusing on nutrient stratification and algal blooms. We hypothesized that nutrient levels in eutrophic waters with stable stratification correlate with HAB magnitude and that disruption of stratification triggers blooms due to nutrient shifts. A 38-day sampling campaign in Gaoyang Lake (April 16-May 23, 2022) revealed that consistent weather between April 26 and May 16 led to a surface density layer, restricting nutrient transfer and causing a bloom with 173.0 μg L-1 Chl-a on May 1. After a heavy rain on May 18, a peak bloom on May 20, dominated by Ceratium hirundinella, showed 533 μg L-1 Chl-a. There was a significant negative correlation between Cyanobacteria and C. hirundinella biomasses (r = -0.296, P < 0.01), highlighting nutrient availability and physical stability's roles in regulating HABs.
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Affiliation(s)
- Xuexing Yao
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China; Great Lakes Institute for Environmental Research, University of Windsor, N9B 3P4, Ontario, Canada
| | - Zenghui Song
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Guanglang Yang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Muhammad Waqas Yonas
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Paul B Hamilton
- National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China; Canadian Museum of Nature, 240 McLeod Street, Ottawa K1P 6P4, Ontario, Canada
| | - Amechi S Nwankwegu
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Oluwafemi Adeyeye
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Wei Huang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Xiaojiao Luo
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - Abdelrahman M Hassaan
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China
| | - G Douglas Haffner
- National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China; Great Lakes Institute for Environmental Research, University of Windsor, N9B 3P4, Ontario, Canada
| | - Lei Zhang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; National Base of International S&T Collaboration on Water Environmental Monitoring and Simulation in TGR Region, Southwest University, Chongqing, 400715, China; Great Lakes Institute for Environmental Research, University of Windsor, N9B 3P4, Ontario, Canada.
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Kinoshita N, Nagasato C, Motomura T. Calcium Control of the Sign of Phototaxis in Brown Algal Gametes of Mutimo cylindricus. Photochem Photobiol 2017; 93:1216-1223. [PMID: 28295378 DOI: 10.1111/php.12748] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 02/06/2017] [Indexed: 11/26/2022]
Abstract
Brown algal swarmers usually exhibit positive or negative phototaxis. Such behaviors influence the increasing or decreasing dispersal distance or colonization on the new substratum. We confirmed that the sign of phototaxis (negative or positive) in male gametes of Mutimo cylindricus was affected by extracellular Ca2+ influx through Ca2+ channels. Under the control condition (10-2 m [Ca2+ ]), male gametes swimming with a helical rotation of their cell body mostly showed positive phototaxis. At 10-3 m [Ca2+ ], more than half of the male gametes showed positive phototaxis, whereas the others showed negative phototaxis. From 10-4 -10-5 m [Ca2+ ], the phototactic sign changed to negative. When these negative phototactic gametes were transferred back to the control condition, the phototactic sign reverted to positive. At 10-6 m [Ca2+ ], some of male gametes showed negative phototaxis, but most showed no phototaxis or flagellar beating. Lanthanum, a Ca2+ channel blocker, affected the sign of phototaxis at 10-4 m [La3+ ] under 10-2 m [Ca2+ ], and male gametes mostly showed negative phototaxis. A further increase in [La3+ ] inhibited phototaxis and flagellar beating. These results pointed out the involvement of Ca2+ channels that were blocked by La3+ in phototaxis and flagellar beating.
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Affiliation(s)
- Nana Kinoshita
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, Hokkaido, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, Hokkaido, Japan
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Kinoshita N, Nagasato C, Motomura T. Phototaxis and chemotaxis of brown algal swarmers. JOURNAL OF PLANT RESEARCH 2017; 130:443-453. [PMID: 28271338 DOI: 10.1007/s10265-017-0914-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 01/08/2017] [Indexed: 06/06/2023]
Abstract
Brown algae exhibit three patterns of sexual reproduction: isogamy, anisogamy, and oogamy. Unicellular swarmers including gametes and zoospores bear two heterogenous flagella, an anterior flagellum with mastigonemes (fine tripartite hairs) and a posterior one. In seawater, these flagellates usually receive physico-chemical signals for finding partners and good habitats. It is well known that brown algal swarmers change their swimming direction depending on blue light (phototaxis), and male gametes do so, based on the sex pheromones from female gametes (chemotaxis). In recent years, the comparative analysis of chemotaxis in isogamy, anisogamy, and oogamy has been conducted. In this paper, we focused on the phototaxis and chemotaxis of brown algal gametes comparing the current knowledge with our recent studies.
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Affiliation(s)
- Nana Kinoshita
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
| | - Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, Hokkaido, 051-0013, Japan
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, Hokkaido, 051-0013, Japan.
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Ozasa K, Won J, Song S, Tamaki S, Ishikawa T, Maeda M. Temporal change of photophobic step-up responses of Euglena gracilis investigated through motion analysis. PLoS One 2017; 12:e0172813. [PMID: 28234984 PMCID: PMC5325543 DOI: 10.1371/journal.pone.0172813] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 02/09/2017] [Indexed: 11/28/2022] Open
Abstract
The adaptation to a strong light is one of the essential characteristics of green algae, yet lacking relatively the information about the photophobic responses of Eukaryotic microalgae. We investigated the photophobic step-up responses of Euglena gracilis over a time course of several hours with alternated repetition of blue-light pulse illumination and spatially patterned blue-light illumination. Four distinctive photophobic motions in response to strong blue light were identified in a trace image analysis, namely on-site rotation, running and tumbling, continuous circular swimming, and unaffected straightforward swimming. The cells cultured in autotrophic conditions under weak light showed mainly the on-site rotation response at the beginning of blue-light illumination, but they acquired more blue-light tolerant responses of running and tumbling, circular swimming, or straightforward swimming. The efficiency of escaping from a blue-light illuminated area improved markedly with the development of these photophobic motions. Time constant of 3.0 h was deduced for the evolution of photophobic responses of E. gracilis. The nutrient-rich metabolic status of the cells resulting from photosynthesis during the experiments, i.e., the accumulation of photosynthesized nutrient products in balance between formation and consumption, was the main factor responsible for the development of photophobic responses. The reduction-oxidation status in and around E. gracilis cells did not affect their photophobic responses significantly, unlike the case of photophobic responses and phototaxis of Chlamydomonas reinhardtii cells. This study shows that the evolution of photophobic motion type of E. gracilis is dominated mainly by the nutrient metabolic status of the cells. The fact suggests that the nutrient-rich cells have a higher threshold for switching the flagellar motion from straightforward swimming to rotation under a strong light.
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Affiliation(s)
| | - June Won
- Department of Mechanical Convergence Engineering, Hanyang University, Seongdong-gu, Seoul, Korea
| | - Simon Song
- Department of Mechanical Convergence Engineering, Hanyang University, Seongdong-gu, Seoul, Korea
- Institute of Nano Science and Technology, Hanyang University, Seongdong-gu, Seoul, Korea
| | - Shun Tamaki
- Department of Applied Bioscience and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Takahiro Ishikawa
- Department of Applied Bioscience and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo, Japan
| | - Mizuo Maeda
- Bioengineering Lab, RIKEN, Wako, Saitama, Japan
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Häder DP, Iseki M. Photomovement in Euglena. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:207-235. [DOI: 10.1007/978-3-319-54910-1_11] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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The Flux of Euglena gracilis Cells Depends on the Gradient of Light Intensity. PLoS One 2016; 11:e0168114. [PMID: 28033336 PMCID: PMC5199022 DOI: 10.1371/journal.pone.0168114] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/27/2016] [Indexed: 12/20/2022] Open
Abstract
We have quantified the photomovement behavior of a suspension of Euglena gracilis representing a behavioral response to a light gradient. Despite recent measurements of phototaxis and photophobicity, the details of macroscopic behavior of cell photomovements under conditions of light intensity gradients, which are critical to understand recent experiments on spatially localized bioconvection patterns, have not been fully understood. In this paper, the flux of cell number density under a light intensity gradient was measured by the following two experiments. In the first experiment, a capillary containing the cell suspension was illuminated with different light intensities in two regions. In the steady state, the differences of the cell numbers in the two regions normalized by the total number were proportional to the light difference, where the light intensity difference ranged from 0.5-2.0 μmol m-2 s-1. The proportional coefficient was positive (i.e., the bright region contained many microorganisms) when the mean light intensity was weak (1.25 μmol m-2 s-1), whereas it was negative when the mean intensity was strong (13.75 μmol m-2 s-1). In the second experiment, a shallow rectangular container of the suspension was illuminated with stepwise light intensities. The cell number density distribution exhibited a single peak at the position where the light intensity was about Ic ≃ 3.8 μmol m-2 s-1. These results suggest that the suspension of E. gracilis responded to the light gradient and that the favorable light intensity was Ic.
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Shikata T, Matsunaga S, Kuwahara Y, Iwahori S, Nishiyama Y. Light spectrum regulates cell accumulation during daytime in the raphidophyte Chattonella antiqua causing noxious red tides. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 160:128-33. [DOI: 10.1016/j.jphotobiol.2016.03.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/29/2016] [Indexed: 11/30/2022]
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Autonomous oscillation/separation of cell density artificially induced by optical interlink feedback as designed interaction between two isolated microalgae chips. Sci Rep 2016; 6:24602. [PMID: 27098710 PMCID: PMC4838927 DOI: 10.1038/srep24602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 04/03/2016] [Indexed: 11/09/2022] Open
Abstract
We demonstrate a designed interaction between two isolated cell populations of Euglena gracilis and Chlamydomonas reinhardtii, separately confined in two 25-square micro-aquariums of lab-on-chip size. The interaction was realized by interlinking two identical optical feedback systems, which measured the cell distribution. To analyze the cell populations, we measured the cell distribution in the 25 squares and irradiated the cells with a blue light pattern as an external stimulus. The cell distribution dataset was exchanged between the two systems. Governed by a designed interaction algorithm, the feedback systems produced a dynamic blue light illumination pattern that evoked the photophobic responses of both species. We also induced autonomous cell density oscillation and cell distribution separation and clustering, and analyzed how the types and diversities of the photophobic responses affected the oscillation period and separation and clustering. We conclude that artificial interlink feedback is a promising method for investigating diverse cell-cell interactions in ecological communities, and for developing soft-computing applications with living cells.
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Takahashi F. Blue-light-regulated transcription factor, Aureochrome, in photosynthetic stramenopiles. JOURNAL OF PLANT RESEARCH 2016; 129:189-197. [PMID: 26781435 DOI: 10.1007/s10265-016-0784-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/23/2015] [Indexed: 06/05/2023]
Abstract
During the course of evolution through various endosymbiotic processes, diverse photosynthetic eukaryotes acquired blue light (BL) responses that do not use photosynthetic pathways. Photosynthetic stramenopiles, which have red algae-derived chloroplasts through secondary symbiosis, are principal primary producers in aquatic environments, and play important roles in ecosystems and aquaculture. Through secondary symbiosis, these taxa acquired BL responses, such as phototropism, chloroplast photo-relocation movement, and photomorphogenesis similar to those which green plants acquired through primary symbiosis. Photosynthetic stramenopile BL receptors were undefined until the discovery in 2007, of a new type of BL receptor, the aureochrome (AUREO), from the photosynthetic stramenopile alga, Vaucheria. AUREO has a bZIP domain and a LOV domain, and thus BL-responsive transcription factor. AUREO orthologs are only conserved in photosynthetic stramenopiles, such as brown algae, diatoms, and red tide algae. Here, a brief review is presented of the role of AUREOs as photoreceptors for these diverse BL responses and their biochemical properties in photosynthetic stramenopiles.
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Affiliation(s)
- Fumio Takahashi
- College of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
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Wagner I, Braun M, Slenzka K, Posten C. Photobioreactors in Life Support Systems. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015. [PMID: 26206570 DOI: 10.1007/10_2015_327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Life support systems for long-term space missions or extraterrestrial installations have to fulfill major functions such as purification of water and regeneration of atmosphere as well as the generation of food and energy. For almost 60 years ideas for biological life support systems have been collected and various concepts have been developed and tested. Microalgae as photosynthetic organisms have played a major role in most of these concepts. This review deals with the potentials of using eukaryotic microalgae for life support systems and highlights special requirements and frame conditions for designing space photobioreactors especially regarding illumination and aeration. Mono- and dichromatic illumination based on LEDs is a promising alternative for conventional systems and preliminary results yielded higher photoconversion efficiencies (PCE) for dichromatic red/blue illumination than white illumination. Aeration for microgravity conditions should be realized in a bubble-free manner, for example, via membranes. Finally, a novel photobioreactor concept for space application is introduced being parameterized and tested with the microalga Chlamydomonas reinhardtii. This system has already been tested during two parabolic flight campaigns.
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Affiliation(s)
- Ines Wagner
- Department Bioprocess Engineering, KIT, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, Karlsruhe, Germany
| | - Markus Braun
- OHB Ag Life Sciences, Universitätsallee 27-29, Bremen, Germany
| | - Klaus Slenzka
- Gravitational Biology, DLR, Königswinterer Str. 522-524, Bonn, Germany.
| | - Clemens Posten
- Department Bioprocess Engineering, KIT, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, Karlsruhe, Germany
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Ozasa K, Lee J, Song S, Maeda M. Transient freezing behavior in photophobic responses of Euglena gracilis investigated in a microfluidic device. PLANT & CELL PHYSIOLOGY 2014; 55:1704-1712. [PMID: 25074906 DOI: 10.1093/pcp/pcu101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We found that the transient freezing behavior in photophobic responses of Euglena gracilis is a good indicator of the metabolic status of the cells. The transient blue light photophobic responses of E. gracilis cells were investigated on-chip using a new measurement, 'trace momentum' (TM), to evaluate their swimming activity quantitatively in real time. When blue light of intensity >30 mW cm(-2) was repeatedly switched on and off, a large negative spike in the TM was observed at the onset of the 'blue-light-off' phase. Single-cell trace analysis at a blue light intensity of 40 mW cm(-2) showed that 48% (on average, n = 15) of tumbling Euglena cells ceased activity ('freezing') for 2-30 s at the onset of blue-light-off before commencing forward motion in a straight line (termed 'straightforward swimming'), while 45% smoothly commenced straightforward swimming without delay. The proportion of freezing Euglena cells depended on the blue light intensity (only 20% at 20 mW cm(-2)). When the cells were stimulated by four blue light pulses at the higher intensity, without pre-exposure, the transient freezing behavior was more prominent but, on repeating the stimuli after an 80 min interval in red light, the same cells did not freeze. This shows that the metabolism of the cells had changed to anti-freezing during the interval. The relationship between the interval time with/without light irradiation and the blue light adaptation was elucidated experimentally. The origin of the freezing behavior is considered to be a shortage of a metabolic substance that promotes smooth switching of flagellum movement from in situ rotation mode to a straightforward swimming mode.
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Affiliation(s)
- Kazunari Ozasa
- Bioengineering Lab., RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 Japan
| | - Jeesoo Lee
- Department of Mechanical Convergence Engineering, Hanyang University, 17 Haendang-dong, Seongdong-gu, Seoul, 133-791, Korea
| | - Simon Song
- Department of Mechanical Convergence Engineering, Hanyang University, 17 Haendang-dong, Seongdong-gu, Seoul, 133-791, Korea
| | - Mizuo Maeda
- Bioengineering Lab., RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 Japan
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13
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Abstract
Phototaxis in the broadest sense means positive or negative displacement along a light gradient or vector. Prokaryotes most often use a biased random walk strategy, employing type I sensory rhodopsin photoreceptors and two-component signalling to regulate flagellar reversal. This strategy only allows phototaxis along steep light gradients, as found in microbial mats or sediments. Some filamentous cyanobacteria evolved the ability to steer towards a light vector. Even these cyanobacteria, however, can only navigate in two dimensions, gliding on a surface. In contrast, eukaryotes evolved the capacity to follow a light vector in three dimensions in open water. This strategy requires a polarized organism with a stable form, helical swimming with cilia and a shading or focusing body adjacent to a light sensor to allow for discrimination of light direction. Such arrangement and the ability of three-dimensional phototactic navigation evolved at least eight times independently in eukaryotes. The origin of three-dimensional phototaxis often followed a transition from a benthic to a pelagic lifestyle and the acquisition of chloroplasts either via primary or secondary endosymbiosis. Based on our understanding of the mechanism of phototaxis in single-celled eukaryotes and animal larvae, it is possible to define a series of elementary evolutionary steps, each of potential selective advantage, which can lead to pelagic phototactic navigation. We can conclude that it is relatively easy to evolve phototaxis once cell polarity, ciliary swimming and a stable cell shape are present.
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Affiliation(s)
- Gáspár Jékely
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany.
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Häder DP, Lebert M. The Photoreceptor for Phototaxis in the Photosynthetic Flagellate Euglena gracilis. Photochem Photobiol 2008. [DOI: 10.1111/j.1751-1097.1998.tb09679.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Evangelista V, Passarelli V, Barsanti L, Gualtieri P. Fluorescence Behavior of Euglena Photoreceptor¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2003)0780093fboep2.0.co2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Häder DP, Richter P, Lebert M. Signal transduction in gravisensing of flagellates. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/sita.200600104] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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17
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Yoshikawa S, Suzuki T, Watanabe M, Iseki M. Kinetic analysis of the activation of photoactivated adenylyl cyclase (PAC), a blue-light receptor for photomovements of Euglena. Photochem Photobiol Sci 2005; 4:727-31. [PMID: 16121284 DOI: 10.1039/b417212d] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoactivated adenylyl cyclase (PAC) was first purified from a photosensing organelle (the paraflagellar body) of the unicellular flagellate Euglena gracilis, and is regarded as the photoreceptor for the step-up photophobic response. Here, we report the kinetic properties of photoactivation of PAC and a change in intracellular cAMP levels upon blue light irradiation. Activation of PAC was dependent both on photon fluence rate and duration of irradiation, between which reciprocity held well in the range of 2--50 micromol m(-2) s(-1)(total fluence of 1200 micromol m(-2)). Intermittent irradiation also caused activation of PAC in a photon fluence-dependent manner irrespective of cycle periods. Wavelength dependency of PAC activation showed prominent peaks in the UV-B/C, UV-A and blue regions of the spectrum. The time course of the changes in intracellular cAMP levels corresponded well with that of the step-up photophobic response. From this and the kinetic properties of PAC photoactivation, we concluded that an increase in intracellular cAMP levels evoked by photoactivation of PAC is a key event of the step-up photophobic response.
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Affiliation(s)
- Shinya Yoshikawa
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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Ntefidou M, Iseki M, Watanabe M, Lebert M, Häder DP. Photoactivated adenylyl cyclase controls phototaxis in the flagellate Euglena gracilis. PLANT PHYSIOLOGY 2003; 133:1517-1521. [PMID: 14630964 PMCID: PMC300708 DOI: 10.1104/pp.103.034223] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2003] [Revised: 10/07/2003] [Accepted: 10/09/2003] [Indexed: 05/24/2023]
Abstract
Euglena gracilis, a unicellular freshwater protist exhibits different photomovement responses, such as phototaxis (oriented movement toward or away from the light source) and photophobic (abrupt turn in response to a rapid increase [step-up] or decrease [step-down] in the light fluence rate) responses. Photoactivated adenylyl cyclase (PAC) has been isolated from whole-cell preparations and identified by RNA interference (RNAi) to be the photoreceptor for step-up photophobic responses but not for step-down photophobic responses (M. Iseki, S. Matsunaga, A. Murakami, K. Ohno, K. Shiga, C. Yoshida, M. Sugai, T. Takahashi, T. Hori, M. Watanabe [2002] Nature 415: 1047-1051). The present study shows that knockdown of PAC by RNAi also effectively suppresses both positive and negative phototaxis, indicating for the first time that PAC or a PAC homolog is also the photoreceptor for photoorientation of wild-type E. gracilis. Recovery from RNAi occurred earlier for step-up photophobic responses than for positive and negative phototaxis. In addition, we investigated several phototaxis mutant strains of E. gracilis with different cytological features regarding the stigma and paraxonemal body (PAB; believed to be the location for the phototaxis photoreceptor) as well as Astasia longa, a close relative of E. gracilis. All of the E. gracilis mutant strains had PAC mRNAs, whereas in A. longa, a different but similar mRNA was found and designated AlPAC. Consistently, all of these strains showed no phototaxis but performed step-up photophobic responses, which were suppressed by RNAi of the PAC mRNA. The fact that some of these strains possess a cytologically altered or no PAB demonstrates that at least in these strains, the PAC photoreceptor responsible for the step-up photophobic responses is not located in the PAB.
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Affiliation(s)
- Maria Ntefidou
- Department of Plant Ecophysiology, Friedrich-Alexander University, Staudtstrasse 5, 91058 Erlangen, Germany
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Abstract
To provide new information on the series of structural changes that Euglena photoreceptive proteins undergo inside the photoreceptor in response to light, we measured in vivo emission fluorescence spectra in the stable intermediates of its photocycle. Our emission spectra give a certain indication that fluorescent proteins are present in the Euglena photoreceptor and that they undergo a photocycle. On the basis of our data, we suggested that at least two stable intermediates, one of which is fluorescent, can be discriminated at room temperature and with our time resolution.
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Affiliation(s)
- Valtere Evangelista
- Istituto di Biofisica CNR, Area della Ricerca di Pisa, via Moruzzi 1, Pisa, Italy.
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20
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Chapter 11 Phototaxis of Euglena gracilis—flavins and pterins. COMPREHENSIVE SERIES IN PHOTOSCIENCES 2001. [DOI: 10.1016/s1568-461x(01)80015-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Machemer H. The identification of gravikinesis from ciliates: methods and experience. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1999; 24:867-876. [PMID: 11542633 DOI: 10.1016/s0273-1177(99)00968-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Recent advances in the gravitational physiology of ciliates are reported: the theoretical and experimental assessment of gravikinesis and sedimentation, calculation of gravikinesis using slopes of observed swimming and sedimentation data under hypergravity, orientational distributions of gravikinesis, central and membrane-associated gravitransduction, and the kinetics of activation and relaxation of gravikinesis.
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Affiliation(s)
- H Machemer
- AG Zellulare Erregungsphysiologie, Ruhr-Universitat, Bochum, Germany
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22
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Häder DP, Lebert M, Tahedl H, Richter P. The Erlanger flagellate test (EFT): photosynthetic flagellates in biological dosimeters. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1997. [DOI: 10.1016/s1011-1344(97)00028-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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23
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24
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Lebert M, Hader DP. Effects of hypergravity on the photosynthetic flagellate, Euglena gracilis. JOURNAL OF PLANT PHYSIOLOGY 1997; 150:153-159. [PMID: 11540159 DOI: 10.1016/s0176-1617(97)80195-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Euglena gracilis, a unicellular, photosynthetic flagellate, orients itself by means of gravi- and phototaxis to reach and stay in regions optimal for survival and growth. An improved version of the slow rotating centrifuge microscope, NIZEMI, was used to test wild type and mutant strains for their responses to hypergravity. Wild type cells could actively move against the acceleration vector up to 8.5 gn and were centrifuged down at higher rates. Even at 10.5 gn, the highest value tested, cells were still negative gravitactically oriented as shown by video images. In contrast, all mutant strains as well as Astasia longa, a close relative of Euglena, could move against the acceleration vector under all conditions tested. With increasing accelerations the mean orientation of the populations shifted according to a vectorial addition of gravity and acceleration. The r-value, a statistical measure of the orientation of a population, increased with moderately increased acceleration rates and decreased at higher values. While wild type Euglena and two of the three mutant strains tested were exclusively negative gravitactically, in the third strain as well as in Astasia longa half of the population reacted negative gravitactically and the other half positive gravitactically. This variation of the wild type behavior was observed at moderate acceleration rates. At high accelerations the cells became exclusively positive gravitactic. The obtained results are discussed on the basis of the current model explaining gravitaxis.
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Affiliation(s)
- M Lebert
- Institut fur Botanik und Pharmazeutische Biologie der Friedrich-Alexander-Universitat, Erlangen
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25
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Häder DP, Lebert M. Analysis of photoreceptor proteins of microorganisms by gradient gel electrophoresis and other biochemical separation methods. Electrophoresis 1994; 15:1051-61. [PMID: 7859707 DOI: 10.1002/elps.11501501157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Photoreceptor proteins for photoorientation in microorganisms are usually membrane bound and can be isolated by standard biochemical methods. Three examples are shown: the flagellates Euglena gracilis, Peridinum gatunense and the slime mold Dictyostelium discoideum. The photoreceptor of Euglena is attached to the basis of the flagellum and is composed of at least four chromoproteins which can be separated by gradient sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) fast protein liquid chromatography (FPLC) and isoelectric focusing (IEF); it contains pterins and a flavin as chromophoric groups. The photoreceptor of Peridinium absorbs in the red wavelength band. Though not yet identified in detail, multiple receptors are probably involved, as indicated by fluorescence spectroscopy. Dictyostelium shows positive and negative phototaxis in its amoebal form and exclusively positive phototaxis in its pseudoplasmodial form. It is still open to discussion whether the two stages use separate photoreceptors. From amoebae two photoreceptor pigments have been isolated, showing an absorption which resembles the action spectrum, one membrane bound with a molecular mass of 45 kDa and one cytoplasmic fraction with a molecular mass of 27 kDa.
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Affiliation(s)
- D P Häder
- Institut für Botanik und Pharmazeutische Biologie, Friedrich-Alexander-Universität, Erlangen, Germany
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26
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Stallwitz E, Hader DP. Effects of heavy metals on motility and gravitactic orientation of the flagellate, Euglena gracilis. Eur J Protistol 1994; 30:18-24. [PMID: 11541066 DOI: 10.1016/s0932-4739(11)80194-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effects of copper, mercury, cadmium and lead on the gravitactic orientation of the photosynthetic flagellate Euglena gracilis were investigated. The first two heavy metals reverse the direction of downward swimming (positive gravitaxis) in young cultures (up to 8 days) to an upward swimming (negative gravitaxis); cadmium produced a less pronounced effect. Higher concentrations of heavy metals decrease the precision of orientation as compared to the control due to frequent deviations of the cells from straight paths. Higher concentrations also decrease the swimming velocity of the populations. When the cells were growing in the presence of the heavy metal, copper was effective at > or = 50 microM, cadmium at > or = 3 microM and mercury at > or = 1 microM. Since lead formed insoluble precipitations with the acetate in the growth medium it was tested after the cells were transferred into Tris buffer. Under these conditions lead did not affect the direction of movement or the precision of orientation up to a concentration of 300 microM in the time up to 24 h after the addition of the heavy metal. However, high concentrations of lead strongly decreased the swimming speed of the cells, which was partially reversed with time.
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Affiliation(s)
- E Stallwitz
- Institut fur Botanik und Pharmazeutische Biologie, Friedrich-Alexander-Universitat, Erlangen, Germany
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27
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Stallwitz E, Hädert DP. Motility and phototactic orientation of the flagellate Euglena gracilis impaired by heavy metal ions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1993. [DOI: 10.1016/1011-1344(93)80041-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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29
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Orientation and phototaxis in pseudoplasmodia of an axenic strain of the cellular slime mold,Dictyostelium discoideum. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0147-5975(92)90018-m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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30
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H�der DP, Vogel K. Simultaneous tracking of flagellates in real time by image analysis. J Math Biol 1991. [DOI: 10.1007/bf00168007] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Brodhun B, Hader DP. PHOTORECEPTOR PROTEINS AND PIGMENTS IN THE PARAFLAGELLAR BODY OF THE FLAGELLATE Euglena gracilis. Photochem Photobiol 1990. [DOI: 10.1111/j.1751-1097.1990.tb08695.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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32
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Hader DP, Liu SM. Motility and gravitactic orientation of the flagellate, Euglena gracilis, impaired by artificial and solar UV-B radiation. Curr Microbiol 1990; 21:161-8. [PMID: 11540623 DOI: 10.1007/bf02092116] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The effects of ultraviolet radiation on the gravitactic orientation of the freshwater flagellate, Euglena gracilis, were determined by a real time image analysis system. Both artificial UV radiation and solar radiation in a temperature-controlled growth chamber were employed. Histograms of gravitaxis showed that the degree of orientation decreased with increasing exposure time; this can be quantified using the Rayleigh test and upper quadrant summation. The effects of artificial UV radiation on the orientation are considerably stronger than those of solar radiation, probably because the radiation source emits higher fluence rates below 300 nm than found in solar radiation. The effects of monochromatic ultraviolet radiation on motility have been determined, and an action spectrum has been calculated.
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Affiliation(s)
- D P Hader
- Institute for Botany and Pharmaceutical Biology, Friedrich Alexander University, Erlangen, FRG
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33
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Häder DP, Häder M. Effects of UV radiation on motility, photo-orientation and pigmentation in a freshwater Cryptomonas. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1990; 5:105-14. [PMID: 2111388 DOI: 10.1016/1011-1344(90)85009-l] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effects of UV radiation on photo-orientation, motility and pigmentation have been studied in a freshwater Cryptomonas species. The cells show a pronounced diaphototactic orientation which is affected by UV radiation at 50 mW m-2 within about 90 min. Both the average velocity of the swimming cells and the percentage of motile cells within the population decrease within about the same exposure time. UV radiation also bleaches the cellular pigments.
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Affiliation(s)
- D P Häder
- Institut für Botanik und Pharmazeutische Biologie, Friedrich-Alexander-Universität, Erlangen, F.R.G
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35
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Häder DP, Griebenow K. Orientation of the green flagellate, Euglena gracilis, in a vertical column of water. FEMS Microbiol Lett 1988. [DOI: 10.1111/j.1574-6968.1988.tb02660.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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38
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Inhibition of motility and phototaxis in the green flagellate, Euglena gracilis, by UV-B radiation. Arch Microbiol 1988. [DOI: 10.1007/bf00409712] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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39
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Muehlstein LK, Amon JP, Leffler DL. Phototaxis in the Marine Fungus
Rhizophydium littoreum. Appl Environ Microbiol 1987; 53:1819-21. [PMID: 16347407 PMCID: PMC204006 DOI: 10.1128/aem.53.8.1819-1821.1987] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phototaxis appears to be a factor that influences the dispersal of zoospores of the marine fungus
Rhizophydium littoreum.
By using a quantitative method to study phototaxis, zoospores were found to be positively phototactic toward blue wavelengths of light. White light in the range of 20 to 6,000 microeinsteins m
−2
s
−1
and blue light in the range of 1 to 300 microeinsteins m
−2
s
−1
gave positive responses in the laboratory. Results of field studies confirmed the ability of zoospores to respond to light under natural conditions. Phototaxis may be an important adaptive mechanism which influences vertical migration of zoospores in the photic zone where plant products are available as nutrients.
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Affiliation(s)
- L K Muehlstein
- Department of Biological Sciences, Wright State University, Dayton, Ohio 45435
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40
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Hader DP. Polarotaxis, gravitaxis and vertical phototaxis in the green flagellate, Euglena gracilis. Arch Microbiol 1987; 147:179-83. [PMID: 11536573 DOI: 10.1007/bf00415281] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
A fully automatic computer-controlled video analysis system has been used to study the movement of the green unicellular flagellate, Euglena gracilis in a horizontal or vertical cuvette. In darkness, in the absence of gaseous gradients, most cells swim straight upwards. While in a horizontal cuvette the transition between positive and negative phototaxis is found at about 1.5 W m-2, an excess of 30 W m-2 is required to reverse the upward swimming (due to the combined stimulus of negative gravitaxis and positive phototaxis) in a vertical cuvette. By studying the swimming direction in horizontal and vertical cuvettes in polarized light irradiated from above or from the side, respectively, the dichroic orientation of the photoreceptor molecules can be determined in three dimensions with respect to the axes of the cell; In a horizontal cuvette, in a linearly polarized beam from above, the cells orient predominantly at an angle of about 30 degrees clockwise off the electric dipole transition moment as seen from above. The behavior in a vertical cuvette with polarized light entering from above indicates that the photoreceptor pigments are dichroically oriented 60 degrees counterclockwise from the flagellar plane (seen from the front end of the cell). Experiments with horizontal polarized light indicate that the photoreceptor transition moment deviates 25 degrees clockwise off the long axis of the cell.
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Affiliation(s)
- D P Hader
- Fachbereich Biologie-Botanik, Marburg, Federal Republic of Germany
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41
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42
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Hauder DP. EFFECTS OF SOLAR AND ARTIFICIAL UV IRRADIATION ON MOTILITY AND PHOTOTAXIS IN THE FLAGELLATE, Euglena gracilis. Photochem Photobiol 1986. [DOI: 10.1111/j.1751-1097.1986.tb04721.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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43
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Häder DP, Lebert M, Di Lena MR. New evidence for the mechanism of phototactic orientation ofEuglena gracilis. Curr Microbiol 1986. [DOI: 10.1007/bf01568368] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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44
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45
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H�der DP. Effects of UV-B on motility and photobehavior in the green flagellate, Euglena gracilis. Arch Microbiol 1985. [DOI: 10.1007/bf00423278] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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46
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Reisser W, Häder DP. ROLE OF ENDOSYMBIOTIC ALGAE IN PHOTOKINESIS AND PHOTOPHOBIC RESPONSES OF CILIATES. Photochem Photobiol 1984. [DOI: 10.1111/j.1751-1097.1984.tb03908.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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LIPSON EDWARDD, HÄDER DONATP. VIDEO DATA ACQUISITION FOR MOVEMENT RESPONSES IN INDIVIDUAL ORGANISMS. Photochem Photobiol 1984. [DOI: 10.1111/j.1751-1097.1984.tb08203.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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48
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Role of flavin quenchers and inhibitors in the sensory transduction of the negative phototaxis in the flagellate,Euglena gracilis. Curr Microbiol 1983. [DOI: 10.1007/bf01567202] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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50
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Häder DP, Burkart U. Optical properties of Dictyostelium discoideum pseudoplasmodia responsible for phototactic orientation. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0147-5975(83)90069-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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