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Schmitt FJ, Hüls A, Moldenhauer M, Friedrich T. How electron tunneling and uphill excitation energy transfer support photochemistry in Halomicronema hongdechloris. PHOTOSYNTHESIS RESEARCH 2024; 159:273-289. [PMID: 38198121 DOI: 10.1007/s11120-023-01064-4] [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: 05/31/2023] [Accepted: 11/13/2023] [Indexed: 01/11/2024]
Abstract
Halomicronema hongdechloris, the first cyanobacterium reported to produce the red-shifted chlorophyll f (Chl f) upon acclimation to far-red light, demonstrates remarkable adaptability to diverse light conditions. The photosystem II (PS II) of this organism undergoes reversible changes in its Chl f content, ranging from practically zero under white-light culture conditions to a Chl f: Chl a ratio of up to 1:8 when exposed to far-red light (FRL) of 720-730 nm for several days. Our ps time- and wavelength-resolved fluorescence data obtained after excitation of living H. hongdechloris cells indicate that the Soret band of a far-red (FR) chlorophyll involved in charge separation absorbs around 470 nm. At 10 K, the fluorescence decay at 715-720 nm is still fast with a time constant of 165 ps indicating an efficient electron tunneling process. There is efficient excitation energy transfer (EET) from 715-720 nm to 745 nm with the latter resulting from FR Chl f, which mainly functions as light-harvesting pigment upon adaptation to FRL. From there, excitation energy reaches the primary donor in the reaction center of PS II with an energetic uphill EET mechanism inducing charge transfer. The fluorescence data are well explained with a secondary donor PD1 represented by a red-shifted Chl a molecule with characteristic fluorescence around 715 nm and a more red-shifted FR Chl f with fluorescence around 725 nm as primary donor at the ChlD1 or PD2 position.
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Affiliation(s)
- Franz-Josef Schmitt
- Department of Physics, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120, Halle (Saale), Germany.
| | - Anne Hüls
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Marcus Moldenhauer
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Thomas Friedrich
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
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Klongnoi B, Sresumatchai V, Clypuing H, Wisutthajaree A, Pankam J, Srimaneekarn N, Shrestha B, Khovidhunkit SOP. Histopathological and risk factor analyses of oral potentially malignant disorders and oral cancer in a proactive screening in northeastern Thailand. BMC Oral Health 2022; 22:613. [PMID: 36527041 PMCID: PMC9756922 DOI: 10.1186/s12903-022-02646-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Lip and oral cavity cancer has been reported as the 10th most common cancer in Thailand. Recently, a screening program for oral potentially malignant disorders (OPMDs) and oral cancer was conducted in the northeastern Thailand which took into consideration a total of 371,911 people who resided in the provinces of Buriram, Chaiyaphum, Nakhon Ratchasima, and Surin. METHODS A total of 330,914 subjects were consecutively screened for risk factors of oral cancer by village health volunteers (VHVs) using a questionnaire (S1). Then, 186,710 subjects with one or more risk factors for oral cancer were referred for oral screening by dental auxiliaries or dentists at sub-district level hospitals (S2) where 86,941 subjects were subsequently screened. Afterwards, 1576 subjects with suspicious oral lesions for OPMDs or oral cancer attended local hospitals for further investigation and treatment. Oral medicine specialists, oral surgeons, and local dentists at the district level hospitals performed biopsies and the samples were sent for histopathological analysis. The objectives of the study were to report the histopathology findings from the biopsies obtained from these subjects and the associated risk factors. RESULTS Out of 427 subjects who received biopsies, complete diagnostic results were obtained from 409 patients (462 specimens). The 5 most common histopathological results from these specimens were mild epithelial dysplasia (27.3%), fibroepithelial hyperplasia (14.5%), oral lichen planus/oral lichenoid reactions (11.5%), moderate epithelial dysplasia (8%), and acanthosis with or without hyperkeratosis (5%). Oral squamous cell carcinoma was detected in 14 subjects and 11 other forms of oral cancer were revealed. Among the analyzed risk factors, habitual betel quid chewing was established as a statistically significant risk factor associated with OPMDs and oral cancer. CONCLUSION The most frequently observed histopathological results of clinically suspected oral cancer and OPMDs included mild epithelial dysplasia, fibroepithelial hyperplasia, oral lichen planus/oral lichenoid reactions, moderate epithelial dysplasia, and acanthosis with or without hyperkeratosis. Betel quid chewing habit was found to be associated with OPMDs and oral cancer.
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Affiliation(s)
- Boworn Klongnoi
- grid.10223.320000 0004 1937 0490Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Vanvisa Sresumatchai
- grid.10223.320000 0004 1937 0490Department of Family Health, Faculty of Public Health, Mahidol University, Bangkok, Thailand
| | - Harin Clypuing
- Dental Department, Maharat Nakorn Ratchasima Hospital, Nakhon Ratchasima, Thailand
| | | | - Jintana Pankam
- grid.10223.320000 0004 1937 0490Employee of the Development of Disease Management Model for Oral Cancer with an Integration Network of Screening, Surveillance, and Treatment in North East Health District Grant, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Natchalee Srimaneekarn
- grid.10223.320000 0004 1937 0490Department of Anatomy, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Binit Shrestha
- grid.10223.320000 0004 1937 0490Maxillofacial Prosthetic Unit, Department of Prosthodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Siribang-on Piboonniyom Khovidhunkit
- grid.10223.320000 0004 1937 0490Department of Advanced General Dentistry, Faculty of Dentistry, Mahidol University, 6 Yothi Rd., Rajthewee, Bangkok, 10400 Thailand
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Pinevich AV, Averina SG. On the Edge of the Rainbow: Red-Shifted Chlorophylls and Far-Red Light Photoadaptation in Cyanobacteria. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722602019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Saga Y, Tanaka A, Yamashita M, Shinoda T, Tomo T, Kimura Y. Spectral Properties of Chlorophyll f in the B800 Cavity of Light-harvesting Complex 2 from the Purple Photosynthetic Bacterium Rhodoblastus acidophilus. Photochem Photobiol 2021; 98:169-174. [PMID: 34293183 DOI: 10.1111/php.13491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 11/29/2022]
Abstract
The interactions of chlorophyll (Chl) and bacteriochlorophyll (BChl) pigments with the polypeptides in photosynthetic light-harvesting proteins are responsible for controlling the absorption energy of (B)Chls in protein matrixes. The binding pocket of B800 BChl a in LH2 proteins, which are peripheral light-harvesting proteins in purple photosynthetic bacteria, is useful for studying such structure-property relationships. We report the reconstitution of Chl f, which has the formyl group at the 2-position, in the B800 cavity of LH2 from the purple bacterium Rhodoblastus acidophilus. The Qy absorption band of Chl f in the B800 cavity was shifted by 14 nm to longer wavelength compared to that of the corresponding five-coordinated monomer in acetone. This redshift was larger than that of Chl a and Chl b. Resonance Raman spectroscopy indicated hydrogen bonding between the 2-formyl group of Chl f and the LH2 polypeptide. These results suggest that this hydrogen bonding contributes to the Qy redshift of Chl f. Furthermore, the Qy redshift of Chl f in the B800 cavity was smaller than that of Chl d. This may have arisen from the different patterns of hydrogen bonding between Chl f and Chl d and/or from the steric hindrance of the 3-vinyl group in Chl f.
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Affiliation(s)
- Yoshitaka Saga
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Aiko Tanaka
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Madoka Yamashita
- Department of Chemistry, Faculty of Science and Engineering, Kindai University, Osaka, Japan
| | - Toshiyuki Shinoda
- Graduate School of Science, Tokyo University of Science, Tokyo, Japan
| | - Tatsuya Tomo
- Graduate School of Science, Tokyo University of Science, Tokyo, Japan
| | - Yukihiro Kimura
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
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Oka K, Ueno Y, Yokono M, Shen JR, Nagao R, Akimoto S. Adaptation of light-harvesting and energy-transfer processes of a diatom Phaeodactylum tricornutum to different light qualities. PHOTOSYNTHESIS RESEARCH 2020; 146:227-234. [PMID: 31965467 DOI: 10.1007/s11120-020-00714-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
Fucoxanthin-chlorophyll (Chl) a/c-binding proteins (FCPs) are light-harvesting pigment-protein complexes found in diatoms and brown algae. Due to the characteristic pigments, such as fucoxanthin and Chl c, FCPs can capture light energy in blue-to green regions. A pennate diatom Phaeodactylum tricornutum synthesizes a red-shifted form of FCP under weak or red light, extending a light-absorption ability to longer wavelengths. In the present study, we examined changes in light-harvesting and energy-transfer processes of P. tricornutum cells grown under white- and single-colored light-emitting diodes (LEDs). The red-shifted FCP appears in the cells grown under the green, yellow, and red LEDs, and exhibited a fluorescence peak around 714 nm. Additional energy-transfer pathways are established in the red-shifted FCP; two forms (F713 and F718) of low-energy Chl a work as energy traps at 77 K. Averaged fluorescence lifetimes are prolonged in the cells grown under the yellow and red LEDs, whereas they are shortened in the blue-LED-grown cells. Based on these results, we discussed the light-adaptation machinery of P. tricornutum cells involved in the red-shifted FCP.
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Affiliation(s)
- Kumiko Oka
- Faculty of Science, Kobe University, Kobe, 657-8501, Japan
| | - Yoshifumi Ueno
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Makio Yokono
- Innovation Center, Nippon Flour Mills Co., Ltd, Atsugi, 243-0041, Japan
| | - Jian-Ren Shen
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Ryo Nagao
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.
| | - Seiji Akimoto
- Faculty of Science, Kobe University, Kobe, 657-8501, Japan.
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan.
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Femtosecond visible transient absorption spectroscopy of chlorophyll- f-containing photosystem II. Proc Natl Acad Sci U S A 2020; 117:23158-23164. [PMID: 32868421 DOI: 10.1073/pnas.2006016117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The recently discovered, chlorophyll-f-containing, far-red photosystem II (FR-PSII) supports far-red light photosynthesis. Participation and kinetics of spectrally shifted far-red pigments are directly observable and separated from that of bulk chlorophyll-a We present an ultrafast transient absorption study of FR-PSII, investigating energy transfer and charge separation processes. Results show a rapid subpicosecond energy transfer from chlorophyll-a to the long-wavelength chlorophylls-f/d The data demonstrate the decay of an ∼720-nm negative feature on the picosecond-to-nanosecond timescales, coinciding with charge separation, secondary electron transfer, and stimulated emission decay. An ∼675-nm bleach attributed to the loss of chl-a absorption due to the formation of a cation radical, PD1 +•, is only fully developed in the nanosecond spectra, indicating an unusually delayed formation. A major spectral feature on the nanosecond timescale at 725 nm is attributed to an electrochromic blue shift of a FR-chlorophyll among the reaction center pigments. These time-resolved observations provide direct experimental support for the model of Nürnberg et al. [D. J. Nürnberg et al., Science 360, 1210-1213 (2018)], in which the primary electron donor is a FR-chlorophyll and the secondary donor is chlorophyll-a (PD1 of the central chlorophyll pair). Efficient charge separation also occurs using selective excitation of long-wavelength chlorophylls-f/d, and the localization of the excited state on P720* points to a smaller (entropic) energy loss compared to conventional PSII, where the excited state is shared over all of the chlorin pigments. This has important repercussions on understanding the overall energetics of excitation energy transfer and charge separation reactions in FR-PSII.
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Kato K, Shinoda T, Nagao R, Akimoto S, Suzuki T, Dohmae N, Chen M, Allakhverdiev SI, Shen JR, Akita F, Miyazaki N, Tomo T. Structural basis for the adaptation and function of chlorophyll f in photosystem I. Nat Commun 2020; 11:238. [PMID: 31932639 PMCID: PMC6957486 DOI: 10.1038/s41467-019-13898-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/05/2019] [Indexed: 12/03/2022] Open
Abstract
Chlorophylls (Chl) play pivotal roles in energy capture, transfer and charge separation in photosynthesis. Among Chls functioning in oxygenic photosynthesis, Chl f is the most red-shifted type first found in a cyanobacterium Halomicronema hongdechloris. The location and function of Chl f in photosystems are not clear. Here we analyzed the high-resolution structures of photosystem I (PSI) core from H. hongdechloris grown under white or far-red light by cryo-electron microscopy. The structure showed that, far-red PSI binds 83 Chl a and 7 Chl f, and Chl f are associated at the periphery of PSI but not in the electron transfer chain. The appearance of Chl f is well correlated with the expression of PSI genes induced under far-red light. These results indicate that Chl f functions to harvest the far-red light and enhance uphill energy transfer, and changes in the gene sequences are essential for the binding of Chl f. Chlorophyll f (Chl f) is the most red-shifted Chl in oxygenic photosynthesis but its localization in photosystem I (PSI) has been unknown so far. Here the authors determine the cryo-EM structures of PSI complexes from a Chl f-containing cyanobacterium grown either under white light or far-red light conditions and identify seven Chls f in the far-red light PSI structure, whereas PSI from cells grown under white light contains only Chl a.
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Affiliation(s)
- Koji Kato
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Toshiyuki Shinoda
- Faculty of Science, Tokyo University of Science, Tokyo, 162-8601, Japan
| | - Ryo Nagao
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Seiji Akimoto
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Takehiro Suzuki
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science, Wako, Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science, Wako, Japan
| | - Min Chen
- School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Suleyman I Allakhverdiev
- K.A. Timiryazev Institute of Plant Physiology RAS, Moscow, Russia.,Institute of Basic Biological Problems RAS, Pushchino, Moscow Region, Russia.,M.V. Lomonosov Moscow State University, Moscow, Russia.,Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region, Russia.,Institute of Molecular Biology and Biotechnology ANAS, -Baku, Azerbaijan
| | - Jian-Ren Shen
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan.
| | - Fusamichi Akita
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan. .,Japan Science and Technology Agency, PRESTO, Saitama, 332-0012, Japan.
| | - Naoyuki Miyazaki
- Institute for Protein Research, Laboratory of Protein Synthesis and Expression, Osaka University, Osaka, 565-0871, Japan. .,Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, University of Tsukuba, Ibaraki, 305-8577, Japan.
| | - Tatsuya Tomo
- Faculty of Science, Tokyo University of Science, Tokyo, 162-8601, Japan.
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Zhang Z, Li Z, Yin Y, Li Y, Jia Y, Chen M, Qiu B. Widespread occurrence and unexpected diversity of red‐shifted chlorophyll producing cyanobacteria in humid subtropical forest ecosystems. Environ Microbiol 2019; 21:1497-1510. [DOI: 10.1111/1462-2920.14582] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/24/2019] [Accepted: 03/03/2019] [Indexed: 02/02/2023]
Affiliation(s)
- Zhong‐Chun Zhang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal UniversitySchool of Life Sciences Wuhan Hubei 430079 People's Republic of China
| | - Zheng‐Ke Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal UniversitySchool of Life Sciences Wuhan Hubei 430079 People's Republic of China
| | - Yan‐Chao Yin
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal UniversitySchool of Life Sciences Wuhan Hubei 430079 People's Republic of China
| | - Yaqiong Li
- ARC Centre of Excellence for Translational Photosynthesis and School of Life and Environmental SciencesUniversity of Sydney Sydney New South Wales 2006 Australia
| | - Yu Jia
- State Key Laboratory of Systematic and Evolutionary BotanyInstitute of Botany, The Chinese Academy of Sciences Beijing 100093 People's Republic of China
| | - Min Chen
- ARC Centre of Excellence for Translational Photosynthesis and School of Life and Environmental SciencesUniversity of Sydney Sydney New South Wales 2006 Australia
| | - Bao‐Sheng Qiu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal UniversitySchool of Life Sciences Wuhan Hubei 430079 People's Republic of China
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Chen M, Hernandez-Prieto MA, Loughlin PC, Li Y, Willows RD. Genome and proteome of the chlorophyll f-producing cyanobacterium Halomicronema hongdechloris: adaptative proteomic shifts under different light conditions. BMC Genomics 2019; 20:207. [PMID: 30866821 PMCID: PMC6416890 DOI: 10.1186/s12864-019-5587-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 03/05/2019] [Indexed: 11/26/2022] Open
Abstract
Background Halomicronema hongdechloris was the first cyanobacterium to be identified that produces chlorophyll (Chl) f. It contains Chl a and uses phycobiliproteins as its major light-harvesting components under white light conditions. However, under far-red light conditions H. hongdechloris produces Chl f and red-shifted phycobiliprotein complexes to absorb and use far-red light. In this study, we report the genomic sequence of H. hongdechloris and use quantitative proteomic approaches to confirm the deduced metabolic pathways as well as metabolic and photosynthetic changes in response to different photo-autotrophic conditions. Results The whole genome of H. hongdechloris was sequenced using three different technologies and assembled into a single circular scaffold with a genome size of 5,577,845 bp. The assembled genome has 54.6% GC content and encodes 5273 proteins covering 83.5% of the DNA sequence. Using Tandem Mass Tag labelling, the total proteome of H. hongdechloris grown under different light conditions was analyzed. A total of 1816 proteins were identified, with photosynthetic proteins accounting for 24% of the total mass spectral readings, of which 35% are phycobiliproteins. The proteomic data showed that essential cellular metabolic reactions remain unchanged under shifted light conditions. The largest differences in protein content between white and far-red light conditions reflect the changes to photosynthetic complexes, shifting from a standard phycobilisome and Chl a-based light harvesting system under white light, to modified, red-shifted phycobilisomes and Chl f-containing photosystems under far-red light conditions. Conclusion We demonstrate that essential cellular metabolic reactions under different light conditions remain constant, including most of the enzymes in chlorophyll biosynthesis and photosynthetic carbon fixation. The changed light conditions cause significant changes in the make-up of photosynthetic protein complexes to improve photosynthetic light capture and reaction efficiencies. The integration of the global proteome with the genome sequence highlights that cyanobacterial adaptation strategies are focused on optimizing light capture and utilization, with minimal changes in other metabolic pathways. Our quantitative proteomic approach has enabled a deeper understanding of both the stability and the flexibility of cellular metabolic networks of H. hongdechloris in response to changes in its environment. Electronic supplementary material The online version of this article (10.1186/s12864-019-5587-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Min Chen
- School of Life and Environmental Sciences University of Sydney, Sydney, NSW, 2006, Australia.
| | | | - Patrick C Loughlin
- School of Life and Environmental Sciences University of Sydney, Sydney, NSW, 2006, Australia
| | - Yaqiong Li
- School of Life and Environmental Sciences University of Sydney, Sydney, NSW, 2006, Australia
| | - Robert D Willows
- Department of Molecular Sciences Macquarie University, Sydney, NSW, 2109, Australia.
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Schmitt FJ, Campbell ZY, Bui MV, Hüls A, Tomo T, Chen M, Maksimov EG, Allakhverdiev SI, Friedrich T. Photosynthesis supported by a chlorophyll f-dependent, entropy-driven uphill energy transfer in Halomicronema hongdechloris cells adapted to far-red light. PHOTOSYNTHESIS RESEARCH 2019; 139:185-201. [PMID: 30039357 DOI: 10.1007/s11120-018-0556-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
The phototrophic cyanobacterium Halomicronema hongdechloris shows far-red light-induced accumulation of chlorophyll (Chl) f, but the involvement of the pigment in photosynthetic energy harvesting by photosystem (PS) II is controversially discussed. While H. hongdechloris contains negligible amounts of Chl f in white-light culture conditions, the ratio of Chl f to Chl a is reversibly changed up to 1:8 under illumination with far-red light (720-730 nm). We performed UV-Vis absorption spectroscopy, time-integrated and time-resolved fluorescence spectroscopy for the calculation of decay-associated spectra (DAS) to determine excitation energy transfer (EET) processes between photosynthetic pigments in intact H. hongdechloris filaments. In cells grown under white light, highly efficient EET occurs from phycobilisomes (PBSs) to Chl a with an apparent time constant of about 100 ps. Charge separation occurs with a typical apparent time constant of 200-300 ps from Chl a. After 3-4 days of growth under far-red light, robust Chl f content was observed in H. hongdechloris and EET from PBSs reached Chl f efficiently within 200 ps. It is proposed based on mathematical modeling by rate equation systems for EET between the PBSs and PSII and subsequent electron transfer (ET) that charge separation occurs from Chl a and excitation energy is funneled from Chl f to Chl a via an energetically uphill EET driven by entropy, which is effective because the number of Chl a molecules coupled to Chl f is at least eight- to tenfold larger than the corresponding number of Chl f molecules. The long lifetime of Chl f molecules in contact to a tenfold larger pool of Chl a molecules allows Chl f to act as an intermediate energy storage level, from which the Gibbs free energy difference between Chl f and Chl a can be overcome by taking advantage from the favorable ratio of degeneracy coefficients, which formally represents a significant entropy gain in the Eyring formulation of the Arrhenius law. Direct evidence for energetically uphill EET and charge separation in PSII upon excitation of Chl f via anti-Stokes fluorescence in far-red light-adapted H. hongdechloris cells was obtained: Excitation by 720 nm laser light resulted in robust Chl a fluorescence at 680 nm that was distinctly temperature-dependent and, notably, increased upon DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) treatment in far-red light-adapted cells. Thus, rather than serving as an excitation energy trap, Chl f in far-red light-adapted H. hongdechloris cells is directly contributing to oxygenic photosynthesis at PSII.
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Affiliation(s)
- Franz-Josef Schmitt
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
| | - Züleyha Yenice Campbell
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Mai Vi Bui
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Anne Hüls
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Tatsuya Tomo
- Department of Biology, Faculty of Science, Tokyo University of Science, Kagurazaka 1-3, Shinjuku‑Ku, Tokyo, 162‑8601, Japan
| | - Min Chen
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Eugene G Maksimov
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, Leninskye Gory 1, bld. 24, Moscow, Russian Federation, 119991
| | - Suleyman I Allakhverdiev
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russian Federation, 119992
- Bionanotechnology Laboratory, Institute of Molecular Biology and Biotechnology, Azerbaijan National Academy of Sciences, Matbuat Avenue 2a, 1073, Baku, Azerbaijan
- Moscow Institute of Physics and Technology, Institutsky Lane 9, Dolgoprudny, Moscow Region, Russian Federation, 141700
- Controlled Photobiosynthesis Laboratory, Institute of Plant Physiology, Russian Academy of Sciences, Botanicheskaya Street 35, Moscow, Russian Federation, 127276
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation, 142290
| | - Thomas Friedrich
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany.
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Majumder ELW, Wolf BM, Liu H, Berg RH, Timlin JA, Chen M, Blankenship RE. Subcellular pigment distribution is altered under far-red light acclimation in cyanobacteria that contain chlorophyll f. PHOTOSYNTHESIS RESEARCH 2017; 134:183-192. [PMID: 28895022 DOI: 10.1007/s11120-017-0428-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 08/02/2017] [Indexed: 06/07/2023]
Abstract
Far-Red Light (FRL) acclimation is a process that has been observed in cyanobacteria and algae that can grow solely on light above 700 nm. The acclimation to FRL results in rearrangement and synthesis of new pigments and pigment-protein complexes. In this study, cyanobacteria containing chlorophyll f, Synechococcus sp. PCC 7335 and Halomicronema hongdechloris, were imaged as live cells with confocal microscopy. H. hongdechloris was further studied with hyperspectral confocal fluorescence microscopy (HCFM) and freeze-substituted thin-section transmission electron microscopy (TEM). Under FRL, phycocyanin-containing complexes and chlorophyll-containing complexes were determined to be physically separated and the synthesis of red-form phycobilisome and Chl f was increased. The timing of these responses was observed. The heterogeneity and eco-physiological response of the cells was noted. Additionally, a gliding motility for H. hongdechloris is reported.
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Affiliation(s)
- Erica L-W Majumder
- Departments of Chemistry and Biology, Washington University in St. Louis, One Brookings Dr., St. Louis, MO, 63130, USA
| | - Benjamin M Wolf
- Departments of Chemistry and Biology, Washington University in St. Louis, One Brookings Dr., St. Louis, MO, 63130, USA
| | - Haijun Liu
- Departments of Chemistry and Biology, Washington University in St. Louis, One Brookings Dr., St. Louis, MO, 63130, USA
| | - R Howard Berg
- Donald Danforth Plant Science Center, 975 N Warson Rd, St. Louis, MO, 63132, USA
| | - Jerilyn A Timlin
- Bioenergy and Defense Technologies Department, Sandia National Laboratories, P. O. Box 5800, MS 0895, Albuquerque, NM, 87123, USA
| | - Min Chen
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Robert E Blankenship
- Departments of Chemistry and Biology, Washington University in St. Louis, One Brookings Dr., St. Louis, MO, 63130, USA.
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13
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Ohkubo S, Miyashita H. A niche for cyanobacteria producing chlorophyll f within a microbial mat. THE ISME JOURNAL 2017; 11:2368-2378. [PMID: 28622287 PMCID: PMC5607378 DOI: 10.1038/ismej.2017.98] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/03/2017] [Accepted: 05/15/2017] [Indexed: 11/09/2022]
Abstract
Acquisition of additional photosynthetic pigments enables photosynthetic organisms to survive in particular niches. To reveal the ecological significance of chlorophyll (Chl) f, we investigated the distribution of Chl and cyanobacteria within two microbial mats. In a 7-mm-thick microbial mat beneath the running water of the Nakabusa hot spring, Japan, Chl f was only distributed 4.0-6.5 mm below the surface, where the intensity of far-red light (FR) was higher than that of photosynthetically active radiation (PAR). In the same mat, two ecotypes of Synechococcus and two ecotypes of Chl f-producing Leptolyngbya were detected in the upper and deeper layers, respectively. Only the Leptolyngbya strains could grow when FR was the sole light source. These results suggest that the deeper layer of the microbial mat was a habitat for Chl f-producing cyanobacteria, and Chl f enabled them to survive in a habitat with little PAR.
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Affiliation(s)
- Satoshi Ohkubo
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan
| | - Hideaki Miyashita
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan
- Graduate School of Global and Environmental Studies, Kyoto University, Kyoto, Japan
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14
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Ueno Y, Aikawa S, Niwa K, Abe T, Murakami A, Kondo A, Akimoto S. Variety in excitation energy transfer processes from phycobilisomes to photosystems I and II. PHOTOSYNTHESIS RESEARCH 2017; 133:235-243. [PMID: 28185041 DOI: 10.1007/s11120-017-0345-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/27/2017] [Indexed: 06/06/2023]
Abstract
The light-harvesting antennas of oxygenic photosynthetic organisms capture light energy and transfer it to the reaction centers of their photosystems. The light-harvesting antennas of cyanobacteria and red algae, called phycobilisomes (PBSs), supply light energy to both photosystem I (PSI) and photosystem II (PSII). However, the excitation energy transfer processes from PBS to PSI and PSII are not understood in detail. In the present study, the energy transfer processes from PBS to PSs in various cyanobacteria and red algae were examined in vivo by selectively exciting their PSs or PBSs, and measuring the resulting picosecond to nanosecond time-resolved fluorescences. By observing the delayed fluorescence spectrum of PBS-selective excitation in Arthrospira platensis, we demonstrated that energy transfer from PBS to PSI via PSII (PBS→PSII→PSI transfer) occurs even for PSI trimers. The contribution of PBS→PSII→PSI transfer was species dependent, being largest in the wild-type of red alga Pyropia yezoensis (formerly Porphyra yezoensis) and smallest in Synechococcus sp. PCC 7002. Comparing the time-resolved fluorescence after PSs- and PBS-selective excitation, we revealed that light energy flows from CP43 to CP47 by energy transfer between the neighboring PSII monomers in PBS-PSII supercomplexes. We also suggest two pathways of energy transfer: direct energy transfer from PBS to PSI (PBS→PSI transfer) and indirect transfer through PSII (PBS→PSII→PSI transfer). We also infer that PBS→PSI transfer conveys light energy to a lower-energy red chlorophyll than PBS→PSII→PSI transfer.
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Affiliation(s)
- Yoshifumi Ueno
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
| | - Shimpei Aikawa
- Graduate School of Engineering, Kobe University, Kobe, 657-8501, Japan
| | - Kyosuke Niwa
- Fisheries Technology Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Akashi, Hyogo, 674-0093, Japan
| | - Tomoko Abe
- RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama, 351-0198, Japan
| | - Akio Murakami
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
- Kobe University Research Center for Inland Seas, Awaji, 656-2401, Japan
| | - Akihiko Kondo
- Graduate School of Engineering, Kobe University, Kobe, 657-8501, Japan
| | - Seiji Akimoto
- Graduate School of Science, Kobe University, Kobe, 657-8501, Japan.
- Molecular Photoscience Research Center, Kobe University, Kobe, 657-8501, Japan.
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15
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Allakhverdiev SI, Kreslavski VD, Zharmukhamedov SK, Voloshin RA, Korol'kova DV, Tomo T, Shen JR. Chlorophylls d and f and Their Role in Primary Photosynthetic Processes of Cyanobacteria. BIOCHEMISTRY (MOSCOW) 2017; 81:201-12. [PMID: 27262189 DOI: 10.1134/s0006297916030020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The finding of unique Chl d- and Chl f-containing cyanobacteria in the last decade was a discovery in the area of biology of oxygenic photosynthetic organisms. Chl b, Chl c, and Chl f are considered to be accessory pigments found in antennae systems of photosynthetic organisms. They absorb energy and transfer it to the photosynthetic reaction center (RC), but do not participate in electron transport by the photosynthetic electron transport chain. However, Chl d as well as Chl a can operate not only in the light-harvesting complex, but also in the photosynthetic RC. The long-wavelength (Qy) Chl d and Chl f absorption band is shifted to longer wavelength (to 750 nm) compared to Chl a, which suggests the possibility for oxygenic photosynthesis in this spectral range. Such expansion of the photosynthetically active light range is important for the survival of cyanobacteria when the intensity of light not exceeding 700 nm is attenuated due to absorption by Chl a and other pigments. At the same time, energy storage efficiency in photosystem 2 for cyanobacteria containing Chl d and Chl f is not lower than that of cyanobacteria containing Chl a. Despite great interest in these unique chlorophylls, many questions related to functioning of such pigments in primary photosynthetic processes are still not elucidated. This review describes the latest advances in the field of Chl d and Chl f research and their role in primary photosynthetic processes of cyanobacteria.
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Affiliation(s)
- S I Allakhverdiev
- Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, 127276, Russia.
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16
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Hamada F, Murakami A, Akimoto S. Comparative Analysis of Ultrafast Excitation Energy-Transfer Pathways in Three Strains of Divinyl Chlorophyll a/b-Containing Cyanobacterium, Prochlorococcus marinus. J Phys Chem B 2015; 119:15593-600. [DOI: 10.1021/acs.jpcb.5b10073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fumiya Hamada
- Graduate
School of Science, Kobe University, Kobe 657-8501, Japan
| | - Akio Murakami
- Graduate
School of Science, Kobe University, Kobe 657-8501, Japan
- Kobe University Research Center for Inland Seas, Awaji 656-2401, Japan
| | - Seiji Akimoto
- Graduate
School of Science, Kobe University, Kobe 657-8501, Japan
- Molecular
Photoscience Research Center, Kobe University, Kobe 657-8501, Japan
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17
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Itoh S, Ohno T, Noji T, Yamakawa H, Komatsu H, Wada K, Kobayashi M, Miyashita H. Harvesting Far-Red Light by Chlorophyll f in Photosystems I and II of Unicellular Cyanobacterium strain KC1. PLANT & CELL PHYSIOLOGY 2015; 56:2024-2034. [PMID: 26320210 DOI: 10.1093/pcp/pcv122] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 08/14/2015] [Indexed: 06/04/2023]
Abstract
Cells of a unicellular cyanobacterium strain KC1, which were collected from Japanese fresh water Lake Biwa, formed chlorophyll (Chl) f at 6.7%, Chl a' at 2.0% and pheophytin a at 0.96% with respect to Chl a after growth under 740 nm light. The far-red-acclimated cells (Fr cells) formed extra absorption bands of Chl f at 715 nm in addition to the major Chl a band. Fluorescence lifetimes were measured. The 405-nm laser flash, which excites mainly Chl a in photosystem I (PSI), induced a fast energy transfer to multiple fluorescence bands at 720-760 and 805 nm of Chl f at 77 K in Fr cells with almost no PSI-red-Chl a band. The 630-nm laser flash, which mainly excited photosystem II (PSII) through phycocyanin, revealed fast energy transfer to another set of Chl f bands at 720-770 and 810 nm as well as to the 694-nm Chl a fluorescence band. The 694-nm band did not transfer excitation energy to Chl f. Therefore, Chl a in PSI, and phycocyanin in PSII of Fr cells transferred excitation energy to different sets of Chl f molecules. Multiple Chl f forms, thus, seem to work as the far-red antenna both in PSI and PSII. A variety of cyanobacterial species, phylogenically distant from each other, seems to use a Chl f antenna in far-red environments, such as under dense biomats, in colonies, or under far-red LED light.
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Affiliation(s)
- Shigeru Itoh
- Center for Gene Research, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan
| | - Tomoki Ohno
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Tomoyasu Noji
- Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa, Nagoya 466-8555, Japan
| | - Hisanori Yamakawa
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan
| | - Hirohisa Komatsu
- Division of Materials Science, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Katsuhiro Wada
- Division of Materials Science, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Masami Kobayashi
- Division of Materials Science, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Hideaki Miyashita
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan Graduate School of Global and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
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18
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Gan F, Bryant DA. Adaptive and acclimative responses of cyanobacteria to far-red light. Environ Microbiol 2015; 17:3450-65. [DOI: 10.1111/1462-2920.12992] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/09/2015] [Accepted: 07/17/2015] [Indexed: 01/18/2023]
Affiliation(s)
- Fei Gan
- Department of Biochemistry and Molecular Biology; The Pennsylvania State University; University Park PA 16802 USA
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology; The Pennsylvania State University; University Park PA 16802 USA
- Department of Chemistry and Biochemistry; Montana State University; Bozeman MT 59717 USA
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19
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Watabe K, Mimuro M, Tsuchiya T. Establishment of the forward genetic analysis of the chlorophyll d-dominated cyanobacterium Acaryochloris marina MBIC 11017 by applying in vivo transposon mutagenesis system. PHOTOSYNTHESIS RESEARCH 2015; 125:255-265. [PMID: 25596846 DOI: 10.1007/s11120-015-0082-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 01/07/2015] [Indexed: 06/04/2023]
Abstract
Acaryochloris marina MBIC 11017 possesses chlorophyll (Chl) d as a major Chl, which enables this organism to utilize far-red light for photosynthesis. Thus, the adaptation mechanism of far-red light utilization, including Chl d biosynthesis, has received much attention, though a limited number of reports on this subject have been published. To identify genes responsible for Chl d biosynthesis and adaptation to far-red light, molecular genetic analysis of A. marina was required. We developed a transformation system for A. marina and introduced expression vectors into A. marina. In this study, the high-frequency in vivo transposon mutagenesis system recently established by us was applied to A. marina. As a result, we obtained mutants with the transposon in their genomic DNA at various positions. By screening transposon-tagged mutants, we isolated a mutant (Y1 mutant) that formed a yellow colony on agar medium. In the Y1 mutant, the transposon was inserted into the gene encoding molybdenum cofactor biosynthesis protein A (MoaA). The Y1 mutant was functionally complemented by introducing the moaA gene or increasing the ammonium ion in the medium. These results indicate that the mutation of the moaA gene reduced nitrate reductase activity, which requires molybdenum cofactor, in the Y1 mutant. This is the first successful forward genetic analysis of A. marina, which will lead to the identification of genes responsible for adaptation to far-red light.
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Affiliation(s)
- Kazuyuki Watabe
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
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20
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Akimoto S, Shinoda T, Chen M, Allakhverdiev SI, Tomo T. Energy transfer in the chlorophyll f-containing cyanobacterium, Halomicronema hongdechloris, analyzed by time-resolved fluorescence spectroscopies. PHOTOSYNTHESIS RESEARCH 2015; 125:115-122. [PMID: 25648637 DOI: 10.1007/s11120-015-0091-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 01/21/2015] [Indexed: 06/04/2023]
Abstract
We prepared thylakoid membranes from Halomicronema hongdechloris cells grown under white fluorescent light or light from far-red (740 nm) light-emitting diodes, and observed their energy-transfer processes shortly after light excitation. Excitation-relaxation processes were examined by steady-state and time-resolved fluorescence spectroscopies. Two time-resolved fluorescence techniques were used: time-correlated single photon counting and fluorescence up-conversion methods. The thylakoids from the cells grown under white light contained chlorophyll (Chl) a of different energies, but were devoid of Chl f. At room temperature, the excitation energy was equilibrated among the Chl a pools with a time constant of 6.6 ps. Conversely, the thylakoids from the cells grown under far-red light possessed both Chl a and Chl f. Two energy-transfer pathways from Chl a to Chl f were identified with time constants of 1.3 and 5.0 ps, and the excitation energy was equilibrated between the Chl a and Chl f pools at room temperature. We also examined the energy-transfer pathways from phycobilisome to the two photosystems under white-light cultivation.
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Affiliation(s)
- Seiji Akimoto
- Molecular Photoscience Research Center, Kobe University, Kobe, 657-8501, Japan,
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21
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Chlorophyll f-driven photosynthesis in a cavernous cyanobacterium. ISME JOURNAL 2015; 9:2108-11. [PMID: 25668158 DOI: 10.1038/ismej.2015.14] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 12/14/2014] [Accepted: 12/22/2014] [Indexed: 12/30/2022]
Abstract
Chlorophyll (Chl) f is the most recently discovered chlorophyll and has only been found in cyanobacteria from wet environments. Although its structure and biophysical properties are resolved, the importance of Chl f as an accessory pigment in photosynthesis remains unresolved. We found Chl f in a cyanobacterium enriched from a cavernous environment and report the first example of Chl f-supported oxygenic photosynthesis in cyanobacteria from such habitats. Pigment extraction, hyperspectral microscopy and transmission electron microscopy demonstrated the presence of Chl a and f in unicellular cyanobacteria found in enrichment cultures. Amplicon sequencing indicated that all oxygenic phototrophs were related to KC1, a Chl f-containing cyanobacterium previously isolated from an aquatic environment. Microsensor measurements on aggregates demonstrated oxygenic photosynthesis at 742 nm and less efficient photosynthesis under 768- and 777-nm light probably because of diminished overlap with the absorption spectrum of Chl f and other far-red absorbing pigments. Our findings suggest the importance of Chl f-containing cyanobacteria in terrestrial habitats.
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