1
|
Ye ZP, An T, Govindjee G, Robakowski P, Stirbet A, Yang XL, Hao XY, Kang HJ, Wang FB. Addressing the long-standing limitations of double exponential and non-rectangular hyperbolic models in quantifying light-response of electron transport rates in different photosynthetic organisms under various conditions. FRONTIERS IN PLANT SCIENCE 2024; 15:1332875. [PMID: 38476692 PMCID: PMC10929714 DOI: 10.3389/fpls.2024.1332875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/02/2024] [Indexed: 03/14/2024]
Abstract
The models used to describe the light response of electron transport rate in photosynthesis play a crucial role in determining two key parameters i.e., the maximum electron transport rate (J max) and the saturation light intensity (I sat). However, not all models accurately fit J-I curves, and determine the values of J max and I sat. Here, three models, namely the double exponential (DE) model, the non-rectangular hyperbolic (NRH) model, and a mechanistic model developed by one of the coauthors (Z-P Ye) and his coworkers (referred to as the mechanistic model), were compared in terms of their ability to fit J-I curves and estimate J max and I sat. Here, we apply these three models to a series of previously collected Chl a fluorescence data from seven photosynthetic organisms, grown under different conditions. Our results show that the mechanistic model performed well in describing the J-I curves, regardless of whether photoinhibition/dynamic down-regulation of photosystem II (PSII) occurs. Moreover, both J max and I sat estimated by this model are in very good agreement with the measured data. On the contrary, although the DE model simulates quite well the J-I curve for the species studied, it significantly overestimates both the J max of Amaranthus hypochondriacus and the I sat of Microcystis aeruginosa grown under NH4 +-N supply. More importantly, the light intensity required to achieve the potential maximum of J (J s) estimated by this model exceeds the unexpected high value of 105 μmol photons m-2 s-1 for Triticum aestivum and A. hypochondriacus. The NRH model fails to characterize the J-I curves with dynamic down-regulation/photoinhibition for Abies alba, Oryza sativa and M. aeruginosa. In addition, this model also significantly overestimates the values of J max for T. aestivum at 21% O2 and A. hypochondriacus grown under normal condition, and significantly underestimates the values of J max for M. aeruginosa grown under NO3 -N supply. Our study provides evidence that the 'mechanistic model' is much more suitable than both the DE and NRH models in fitting the J-I curves and in estimating the photosynthetic parameters. This is a powerful tool for studying light harvesting properties and the dynamic down-regulation of PSII/photoinhibition.
Collapse
Affiliation(s)
- Zi-Piao Ye
- The Institute of Biophysics in College of Mathematics and Physics, Jinggangshan University, Ji’an, Jiangxi, China
| | - Ting An
- School of Biological Sciences and Engineering, Jiangxi Agriculture University, Nanchang, China
| | - Govindjee Govindjee
- Plant Biology, Biochemistry, and Biophysics, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Piotr Robakowski
- Faculty of Forestry and Wood Technology, Poznan University of Life Sciences, Poznan, Poland
| | | | - Xiao-Long Yang
- School of Life Sciences, University of Nantong, Nantong, Jiangsu, China
| | - Xing-Yu Hao
- College of Agriculture/State Key Laboratory of Sustainable Dry land Agriculture Jointly Built by the Shanxi Province and the Ministry of Science and Technology, Shanxi Agricultural University, Taiyuan, Shanxi, China
| | - Hua-Jing Kang
- Southern Zhejiang Key Laboratory of Crop Breeding of Zhejiang Province, Wenzhou Academy of Agricultural Sciences, Wenzhou, Zhejiang, China
| | - Fu-Biao Wang
- The Institute of Biophysics in College of Mathematics and Physics, Jinggangshan University, Ji’an, Jiangxi, China
| |
Collapse
|
2
|
Shi T, Fan D, Xu C, Zheng G, Zhong C, Feng F, Chow WS. The Fitting of the OJ Phase of Chlorophyll Fluorescence Induction Based on an Analytical Solution and Its Application in Urban Heat Island Research. PLANTS (BASEL, SWITZERLAND) 2024; 13:452. [PMID: 38337985 PMCID: PMC10857409 DOI: 10.3390/plants13030452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/28/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
Chlorophyll (Chl) fluorescence induction (FI) upon a dark-light transition has been widely analyzed to derive information on initial events of energy conversion and electron transfer in photosystem II (PSII). However, currently, there is no analytical solution to the differential equation of QA reduction kinetics, raising a doubt about the fitting of FI by numerical iteration solution. We derived an analytical solution to fit the OJ phase of FI, thereby yielding estimates of three parameters: the functional absorption cross-section of PSII (σPSII), a probability parameter that describes the connectivity among PSII complexes (p), and the rate coefficient for QA- oxidation (kox). We found that σPSII, p, and kox exhibited dynamic changes during the transition from O to J. We postulated that in high excitation light, some other energy dissipation pathways may vastly outcompete against excitation energy transfer from a closed PSII trap to an open PSII, thereby giving the impression that connectivity seemingly does not exist. We also conducted a case study on the urban heat island effect on the heat stability of PSII using our method and showed that higher-temperature-acclimated leaves had a greater σPSII, lower kox, and a tendency of lower p towards more shade-type characteristics.
Collapse
Affiliation(s)
- Tongxin Shi
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Dayong Fan
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Chengyang Xu
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Guoming Zheng
- Yi Zong Qi Technology (Beijing) Co., Ltd., Beijing 100095, China
| | - Chuanfei Zhong
- Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100093, China
| | - Fei Feng
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing 100083, China; (T.S.)
| | - Wah Soon Chow
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT 2601, Australia
| |
Collapse
|
3
|
Liu L, Fu Z, Wang X, Xu C, Gan C, Fan D, Soon Chow W. Exposed anthocyanic leaves of Prunus cerasifera are special shade leaves with high resistance to blue light but low resistance to red light against photoinhibition of photosynthesis. ANNALS OF BOTANY 2023; 132:163-177. [PMID: 37382489 PMCID: PMC10550276 DOI: 10.1093/aob/mcad086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/28/2023] [Indexed: 06/30/2023]
Abstract
BACKGROUND AND AIMS The photoprotective role of foliar anthocyanins has long been ambiguous: exacerbating, being indifferent to or ameliorating the photoinhibition of photosynthesis. The photoinhibitory light spectrum and failure to separate photo-resistance from repair, as well as the different methods used to quantify the photo-susceptibility of the photosystems, could lead to such a discrepancy. METHODS We selected two congeneric deciduous shrubs, Prunus cerasifera with anthocyanic leaves and Prunus triloba with green leaves, grown under identical growth conditions in an open field. The photo-susceptibilities of photosystem II (PSII) and photosystem I (PSI) to red light and blue light, in the presence of lincomycin (to block the repair), of exposed leaves were quantified by a non-intrusive P700+ signal from PSI. Leaf absorption, pigments, gas exchange and Chl a fluorescence were also measured. KEY RESULTS The content of anthocyanins in red leaves (P. cerasifera) was >13 times greater than that in green leaves (P. triloba). With no difference in maximum quantum efficiency of PSII photochemistry (Fv/Fm) and apparent CO2 quantum yield (AQY) in red light, anthocyanic leaves (P. cerasifera) showed some shade-acclimated suites, including lower Chl a/b ratio, lower photosynthesis rate, lower stomatal conductance and lower PSII/PSI ratio (on an arbitrary scale), compared with green leaves (P. triloba). In the absence of repair of PSII, anthocyanic leaves (P. cerasifera) showed a rate coefficient of PSII photoinactivation (ki) that was 1.8 times higher than that of green leaves (P. triloba) under red light, but significantly lower (-18 %) under blue light. PSI of both types of leaves was not photoinactivated under blue or red light. CONCLUSIONS In the absence of repair, anthocyanic leaves exhibited an exacerbation of PSII photoinactivation under red light and a mitigation under blue light, which can partially reconcile the existing controversy in terms of the photoprotection by anthocyanins. Overall, the results demonstrate that appropriate methodology applied to test the photoprotection hypothesis of anthocyanins is critical.
Collapse
Affiliation(s)
- Lu Liu
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Zengjuan Fu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiangping Wang
- School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Chengyang Xu
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Changqing Gan
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Dayong Fan
- The Key Laboratory for Silviculture and Conservation of Ministry of Education, College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Wah Soon Chow
- Division of Plant Sciences, Research School of Biology, The Australian National University, Acton, ACT 2601, Australia
| |
Collapse
|
4
|
Zavafer A, Mancilla C, Jolley G, Murakami K. On the concepts and correct use of radiometric quantities for assessing the light environment and their application to plant research. Biophys Rev 2023; 15:385-400. [PMID: 37396445 PMCID: PMC10310645 DOI: 10.1007/s12551-023-01051-y] [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: 06/19/2022] [Accepted: 03/06/2023] [Indexed: 04/07/2023] Open
Abstract
Light is one of the most important factors for photosynthetic organisms to grow. Historically, the amount of light in plant sciences has been referred to as light intensity, irradiance, photosynthetic active radiation, photon flux, photon flux density, etc. On occasion, all these terms are used interchangeably, yet they refer to different physical units and each metric offers distinct information. Even for experts in the fields of plant photobiology, the use of these terms is confusing, and there is a loose implementation of each concept. This makes the use of radiometric units even more confusing to non-experts when looking for ways to measure light, since they could easily feel overwhelmed by the specialized literature. The use of scientific concepts must be accurate, as ambiguity in the use of radiometric quantities can lead to inconsistencies in analysis, thus decreasing the comparability between experiments and to the formulation of incorrect experimental designs. In this review, we provide a simple yet comprehensive view of the use of radiometric quantities in an effort to clarify their meaning and applications. To facilitate understanding, we adopt a minimum amount of mathematical expressions and provide a historical summary of the use of radiometry (with emphasis on plant sciences), examples of uses, and a review of the available instrumentation for radiometric measurements.
Collapse
Affiliation(s)
- Alonso Zavafer
- Department of Engineering, Brock University, St. Catharines, ON Canada
| | - Cristian Mancilla
- Department of Engineering, Brock University, St. Catharines, ON Canada
| | - Gregory Jolley
- Research School of Chemistry, The Australian National University, Canberra, ACT 2600 Australia
| | - Keach Murakami
- Hokkaido Agricultural Research Center, National Agriculture and Food Research Organization, Sapporo, Japan
| |
Collapse
|
5
|
Lysenko V, D. Rajput V, Kumar Singh R, Guo Y, Kosolapov A, Usova E, Varduny T, Chalenko E, Yadronova O, Dmitriev P, Zaruba T. Chlorophyll fluorometry in evaluating photosynthetic performance: key limitations, possibilities, perspectives and alternatives. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2022; 28:2041-2056. [PMID: 36573148 PMCID: PMC9789293 DOI: 10.1007/s12298-022-01263-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/25/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Non-destructive methods for the assessment of photosynthetic parameters of plants are widely applied to evaluate rapidly the photosynthetic performance, plant health, and shifts in plant productivity induced by environmental and cultivation conditions. Most of these methods are based on measurements of chlorophyll fluorescence kinetics, particularly on pulse modulation (PAM) fluorometry. In this paper, fluorescence methods are critically discussed in regard to some their possibilities and limitations inherent to vascular plants and microalgae. Attention is paid to the potential errors related to the underestimation of thylakoidal cyclic electron transport and anoxygenic photosynthesis. PAM-methods are also observed considering the color-addressed measurements. Photoacoustic methods are discussed as an alternative and supplement to fluorometry. Novel Fourier modifications of PAM-fluorometry and photoacoustics are noted as tools allowing simultaneous application of a dual or multi frequency measuring light for one sample.
Collapse
Affiliation(s)
- Vladimir Lysenko
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Vishnu D. Rajput
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Rupesh Kumar Singh
- Centre of Molecular and Environmental Biology, Department of Biology, Campus of Gualtar, University of Minho, Braga, Portugal
| | - Ya Guo
- School of IoT Engineering, Jiangnan University, Wuxi, China
| | - Alexey Kosolapov
- Russian Research Institute for the Integrated Use and Protection of Water Resources, Rostov-on-Don, Russia
| | - Elena Usova
- Russian Research Institute for the Integrated Use and Protection of Water Resources, Rostov-on-Don, Russia
| | - Tatyana Varduny
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Elizaveta Chalenko
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Olga Yadronova
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Pavel Dmitriev
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Tatyana Zaruba
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| |
Collapse
|
6
|
Laisk A. Prying into the green black-box. PHOTOSYNTHESIS RESEARCH 2022; 154:89-112. [PMID: 36114436 DOI: 10.1007/s11120-022-00960-5] [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: 02/09/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
Life-long efforts of the Tartu photosynthesis research group have been summarized. The measurements were facilitated by self-designed instruments, distinct in multifunctionality and fastresponse time. The black-box type kinetical analysis on intact leaves has revealed several physiologically significant features of leaf photosynthesis. Rubisco studies reflected competition for the active site between the substrates and products, linearizing in vivo kinetics compared with the low-Km in vitro responses. Rubisco Activase usually activates only a small part of the Rubisco, making the rest of it a storage protein. Precisely quantifying absorbed photons and the responding transmittance changes, electron flow rates through cytochrome b6f, plastocyanin and photosystem I were measured, revealing competition between the proton-uncoupled cyclic electron flow from PSI to Cyt b6f to P700+ and the proton-coupled linear flow from PSII to Cyt b6f to P700+. Analyzing responses of O2 evolution and Chl fluorescence to ms-length light pulses we concluded that explanation of the sigmoidal fluorescence induction by excitonic connectivity between PSII units is a misconception. Each PSII processes excitation from its own antenna, but the sigmoidicity is caused by rise of the fluorescence yield of the QA-reduced PSII units after their QB site becomes occupied by reduced plastoquinone (or diuron). Unlike respiration, photosynthetic electrons must prepare their acceptor by coupled synthesis of 3ATP/4e-. Feedback regulation of this ratio leads to oscillations under saturating light and CO2, when the rate is Pi-limited. The slow oscillations (period 60s) indicate that the magnitudes of the deflections in the 3ATP/4e- ratio, corrected by regulating cyclic and alternative electron flow (including the Mehler type O2 reduction), are only a fraction of a per cent. The Pi limitation causes slip in the ATP synthase, slightly increasing the basic 12H+/3ATP requirement.
Collapse
Affiliation(s)
- Agu Laisk
- Institute of Technology, University of Tartu, W. Ostwaldi 1, 51011, Tartu, Estonia.
- Estonian Academy of Sciences, Kohtu 6, 10130, Tallinn, Estonia.
| |
Collapse
|
7
|
Serôdio J, Moreira D, Bastos A, Cardoso V, Frommlet J, Frankenbach S. Hysteresis light curves: a protocol for characterizing the time dependence of the light response of photosynthesis. PHOTOSYNTHESIS RESEARCH 2022; 154:57-74. [PMID: 36057004 DOI: 10.1007/s11120-022-00954-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
Photosynthesis vs. light curves (LCs) have played a central role in photosynthesis research for decades. They are the commonest form of describing how photosynthesis responds to changes in light, being frequently used for characterizing photoacclimation. However, LCs are often interpreted exclusively regarding the response to light intensity, the effects of time of exposure not being explicitly considered. This study proposes the use of 'hysteresis light curves' (HLC), an experimental protocol focused on the cumulative effects of light exposure to obtain information on the time dependence of photosynthetic light responses. HLC are generated by exposing samples to a symmetrical sequence of increasing and decreasing light levels. The comparison of the light-increasing and the light-decreasing phases allows the quantification of the hysteresis caused by high-light exposure, the magnitude and direction of which inform on the activation, and subsequent relaxation of high-light-induced photosynthetic processes. HLCs of the chlorophyll fluorescence indices rETR (relative electron transport rate of photosystem II) and Y(NPQ) (index of non-photochemical quenching) were measured on cyanobacteria, algae, and plants, with the aim of identifying main patterns of hysteresis and their diversity. A non-parametric index is proposed to quantify the magnitude and direction of hysteresis in HLCs of rETR and Y(NPQ). The results of this study show that HLCs can provide additional relevant information on the time dependence of the light response of photosynthetic samples, not obtainable from conventional LCs, useful for phenotyping photosynthetic traits, including photoacclimation state and kinetics of light activation and relaxation of electron flow and energy dissipation processes.
Collapse
Affiliation(s)
- João Serôdio
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal.
| | - Daniel Moreira
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Alexandra Bastos
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Vera Cardoso
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Jörg Frommlet
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | - Silja Frankenbach
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| |
Collapse
|
8
|
Quero G, Bonnecarrère V, Simondi S, Santos J, Fernández S, Gutierrez L, Garaycochea S, Borsani O. Genetic architecture of photosynthesis energy partitioning as revealed by a genome-wide association approach. PHOTOSYNTHESIS RESEARCH 2021; 150:97-115. [PMID: 32072456 DOI: 10.1007/s11120-020-00721-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
The photosynthesis process is determined by the intensity level and spectral quality of the light; therefore, leaves need to adapt to a changing environment. The incident energy absorbed can exceed the sink capability of the photosystems, and, in this context, photoinhibition may occur in both photosystem II (PSII) and photosystem I (PSI). Quantum yield parameters analyses reveal how the energy is managed. These parameters are genotype-dependent, and this genotypic variability is a good opportunity to apply mapping association strategies to identify genomic regions associated with photosynthesis energy partitioning. An experimental and mathematical approach is proposed for the determination of an index which estimates the energy per photon flux for each spectral bandwidth (Δλ) of the light incident (QI index). Based on the QI, the spectral quality of the plant growth, environmental lighting, and the actinic light of PAM were quantitatively very similar which allowed an accurate phenotyping strategy of a rice population. A total of 143 genomic single regions associated with at least one trait of chlorophyll fluorescence were identified. Moreover, chromosome 5 gathers most of these regions indicating the importance of this chromosome in the genetic regulation of the photochemistry process. Through a GWAS strategy, 32 genes of rice genome associated with the main parameters of the photochemistry process of photosynthesis in rice were identified. Association between light-harvesting complexes and the potential quantum yield of PSII, as well as the relationship between coding regions for PSI-linked proteins in energy distribution during the photochemical process of photosynthesis is analyzed.
Collapse
Affiliation(s)
- Gastón Quero
- Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Garzón 809, Montevideo, Uruguay.
| | - Victoria Bonnecarrère
- Unidad de Biotecnología, Estación Experimental Wilson Ferreira Aldunate, Instituto Nacional de Investigación Agropecuaria (INIA), Ruta 48, Km 10, Rincón del Colorado, 90200, Canelones, Uruguay
| | - Sebastián Simondi
- Área de Matemática, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo (FCEN-UNCuyo), Padre Contreras 1300, Mendoza, Argentina
| | - Jorge Santos
- Área de Física, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo (FCEN-UNCuyo), Padre Contreras 1300, Mendoza, Argentina
| | - Sebastián Fernández
- Facultad de Ingeniería, Instituto de Ingeniería Eléctrica, Universidad de La República, Julio Herrera y Reissig 565, Montevideo, Uruguay
| | - Lucía Gutierrez
- Department of Agronomy, University of Wisconsin-Madison, 1575 Linden Dr., Madison, WI, 53706, USA
- Departamento de Biometría, Estadística y Cómputos, Facultad de Agronomía, Universidad de la República, Garzón 780, Montevideo, Uruguay
| | - Silvia Garaycochea
- Unidad de Biotecnología, Estación Experimental Wilson Ferreira Aldunate, Instituto Nacional de Investigación Agropecuaria (INIA), Ruta 48, Km 10, Rincón del Colorado, 90200, Canelones, Uruguay
| | - Omar Borsani
- Departamento de Biología Vegetal, Facultad de Agronomía, Universidad de la República, Garzón 809, Montevideo, Uruguay
| |
Collapse
|
9
|
Michel-Rodriguez M, Lefebvre S, Crouvoisier M, Mériaux X, Lizon F. Underwater light climate and wavelength dependence of microalgae photosynthetic parameters in a temperate sea. PeerJ 2021; 9:e12101. [PMID: 34707925 PMCID: PMC8496463 DOI: 10.7717/peerj.12101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 08/11/2021] [Indexed: 11/20/2022] Open
Abstract
Studying how natural phytoplankton adjust their photosynthetic properties to the quantity and quality of underwater light (i.e. light climate) is essential to understand primary production. A wavelength-dependent photoacclimation strategy was assessed using a multi-color pulse-amplitude-modulation chlorophyll fluorometer for phytoplankton samples collected in the spring at 19 locations across the English Channel. The functional absorption cross section of photosystem II, photosynthetic electron transport (PETλ) parameters and non-photochemical quenching were analyzed using an original approach with a sequence of three statistical analyses. Linear mixed-effects models using wavelength as a longitudinal variable were first applied to distinguish the fixed effect of the population from the random effect of individuals. Population and individual trends of wavelength-dependent PETλ parameters were consistent with photosynthesis and photoacclimation theories. The natural phytoplankton communities studied were in a photoprotective state for blue wavelengths (440 and 480 nm), but not for other wavelengths (green (540 nm), amber (590 nm) and light red (625 nm)). Population-detrended PETλ values were then used in multivariate analyses (partial triadic analysis and redundancy analysis) to study ecological implications of PETλ dynamics among water masses. Two wavelength ratios based on the microalgae saturation parameter Ek (in relative and absolute units), related to the hydrodynamic regime and underwater light climate, clearly confirmed the physiological state of microalgae. They also illustrate more accurately that natural phytoplankton communities can implement photoacclimation processes that are influenced by in situ light quality during the daylight cycle in temporarily and weakly stratified water. Ecological implications and consequences of PETλ are discussed in the context of turbulent coastal ecosystems.
Collapse
Affiliation(s)
- Monica Michel-Rodriguez
- Univ. Lille, CNRS, Univ. Littoral Côte d'Opale, UMR 8187 LOG, Laboratoire d'Océanologie et de Géosciences, Lille, France
| | - Sebastien Lefebvre
- Univ. Lille, CNRS, Univ. Littoral Côte d'Opale, UMR 8187 LOG, Laboratoire d'Océanologie et de Géosciences, Lille, France
| | - Muriel Crouvoisier
- Univ. Lille, CNRS, Univ. Littoral Côte d'Opale, UMR 8187 LOG, Laboratoire d'Océanologie et de Géosciences, Lille, France
| | - Xavier Mériaux
- Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, UMR 8187-LOG-Laboratoire d'Océanologie et de Géosciences, Wimereux, France
| | - Fabrice Lizon
- Univ. Lille, CNRS, Univ. Littoral Côte d'Opale, UMR 8187 LOG, Laboratoire d'Océanologie et de Géosciences, Lille, France
| |
Collapse
|
10
|
Zavafer A. A theoretical framework of the hybrid mechanism of photosystem II photodamage. PHOTOSYNTHESIS RESEARCH 2021; 149:107-120. [PMID: 34338941 DOI: 10.1007/s11120-021-00843-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 05/04/2021] [Indexed: 06/13/2023]
Abstract
Photodamage of photosystem II is a significant physiological process that is prevalent in the fields of photobiology, photosynthesis research and plant/algal stress. Since its discovery, numerous efforts have been devoted to determine the causes and mechanisms of action of photosystem II photodamage. There are two contrasting hypotheses to explain photodamage: (1) the excitation pressure induced by light absorption by the photosynthetic pigments and (2) direct photodamage of the Mn cluster located at the water-splitting site, which is independent of excitation pressure. While these two hypotheses seemed mutually exclusive, during the last decade, several independent works have proposed an alternative approach indicating that both hypotheses are valid. This was termed the dual hypothesis of photosystem II photodamage, and it postulates that both excess excitation and direct Mn photodamage operate at the same time, independently or in a synergic manner, depending on the type of sample, temperature, light spectrum, or other environmental stressors. In this mini-review, a brief summary of the contrasting hypotheses is presented, followed by recapitulation of key discoveries in the field of photosystem II photodamage of the last decade, and a synthesis of how these works support a full hybrid framework (operation of several mechanisms and their permutations) to explain PSII photodamage. All these are in recognition of Prof. Wah Soon Chow (the Australian National University), one of the key proposers of the dual hypothesis.
Collapse
Affiliation(s)
- Alonso Zavafer
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia.
- Climate Change Cluster (C3), University of Technology Sydney, Sydney, NSW, 2007, Australia.
| |
Collapse
|
11
|
Saucedo-García M, González-Córdova CD, Ponce-Pineda IG, Cano-Ramírez D, Romero-Colín FM, Arroyo-Pérez EE, King-Díaz B, Zavafer A, Gavilanes-Ruíz M. Effects of MPK3 and MPK6 kinases on the chloroplast architecture and function induced by cold acclimation in Arabidopsis. PHOTOSYNTHESIS RESEARCH 2021; 149:201-212. [PMID: 34132948 DOI: 10.1007/s11120-021-00852-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/21/2021] [Indexed: 06/12/2023]
Abstract
Exposure to low, non-freezing temperatures develops freezing tolerance in many plant species. Such process is called cold acclimation. Molecular changes undergone during cold acclimation are orchestrated by signalling networks including MAP kinases. Structure and function of chloroplasts are affected by low temperatures. The aim of this work was to study how the MAP kinases MPK3 and MPK6 are involved in the chloroplast performance upon a long period of cold acclimation. We used Arabidopsis thaliana wild type and mpk3 and mpk6 mutants. Adult plants were acclimated during 7 days at 4 °C and then measurements of PSII performance and chloroplast ultrastructure were carried out. Only the mpk6 acclimated plants showed a high freezing sensitivity. No differences in the PSII function were observed in the plants from the three genotypes exposed to non-acclimated or acclimated conditions. The acclimation of wild-type plants produced severe alterations in the ultrastructure of chloroplast and thylakoids, which was more accentuated in the mpk plants. However, only the mpk6 mutant was unable to internalize the damaged chloroplasts into the vacuole. These results indicate that cold acclimation induces alterations in the chloroplast architecture leading to preserve an optimal performance of PSII. MPK3 and MPK6 are necessary to regulate these morphological changes, but besides, MPK6 is needed to the vacuolization of the damaged chloroplasts, suggesting a role in the chloroplast recycling during cold acclimation. The latter could be quite relevant, since it could explain why this mutant is the only one showing an extremely low freezing tolerance.
Collapse
Affiliation(s)
- Mariana Saucedo-García
- Instituto de Ciencias Agropecuarias, Universidad Autónoma del Estado de Hidalgo, Tulancingo, Hidalgo, México
| | - Carla D González-Córdova
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
| | - I Giordano Ponce-Pineda
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
| | - Dora Cano-Ramírez
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB3 0LJ, UK
| | - Fernanda M Romero-Colín
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
| | - Erik E Arroyo-Pérez
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
| | - Beatriz King-Díaz
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México
| | - Alonso Zavafer
- Research School of Biology, the Australian National University, Canberra, ACT, 2600, Australia
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2001, Australia
| | - Marina Gavilanes-Ruíz
- Dpto. de Bioquímica, Conjunto E. Facultad de Química, Universidad Nacional Autónoma de México, UNAM, Ciudad Universitaria Universitaria, Coyoacán, 04510, México City, México.
| |
Collapse
|
12
|
Gao S, Liu X, Liu Y, Cao B, Chen Z, Xu K. Response of growth, photosynthetic electron transfer, and chloroplast ultrastructure to different LED light combination in green onion (Allium fistulosum L.). PHYSIOLOGIA PLANTARUM 2021; 172:1662-1672. [PMID: 33665820 DOI: 10.1111/ppl.13381] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 02/05/2021] [Indexed: 05/27/2023]
Abstract
With the rapid development of facility agriculture, it has become popular to study the influences of different light qualities on the growth, material metabolism, and morphology of horticultural crops. Last several years, green onions cultivation models have undergone major changes, and facility cultivation has developed rapidly. To determine the impact of light quality on the green onions, we studied the parameters connected to photosynthesis, incorporating growth, and development, photosynthetic rate (Pn ), chlorophyll fluorescence, light response curve, photosynthetic electron transfer, and chloroplast ultrastructure. We roundly analyzed the influences of different LED light combination (white: W, white-blue combination 3:1:WB, white-green combination 3:1:WG, white-yellow combination 3:1:WY, and white-red combination 3:1:WR, light intensity: 500 ± 10 μmol photons m-2 s-1 ) on the photosynthetic performance of green onions. The WB light led to better results than those of the WR, WG, and WY. There were significant performance improvements in leaf area, plant height, stem thickness, relative growth rate (RGR), pigment content, photosynthetic capacity, photosynthetic electron transfer efficiency, and chloroplast ultrastructure integrity. In contrast, plants treated with WG and WY were exposed to appreciably blocked light, but they effectively formed a light protection mechanism. The results of this research not only provided insight into the response mechanism of crop photosynthesis to different light qualities, but they also provided a scientific foundation for better planting green onions.
Collapse
Affiliation(s)
- Song Gao
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| | - Xuena Liu
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| | - Ying Liu
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| | - Bili Cao
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| | - Zijing Chen
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| | - Kun Xu
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
- Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, 271018, China
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, Tai'an, 271018, China
- State Key Laboratory of Crop Biology, Tai'an, 271018, China
| |
Collapse
|
13
|
Zavafer A, Mancilla C. Concepts of photochemical damage of Photosystem II and the role of excessive excitation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C: PHOTOCHEMISTRY REVIEWS 2021. [DOI: 10.1016/j.jphotochemrev.2021.100421] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
14
|
Serôdio J, Campbell DA. Photoinhibition in optically thick samples: Effects of light attenuation on chlorophyll fluorescence-based parameters. J Theor Biol 2021; 513:110580. [PMID: 33444625 DOI: 10.1016/j.jtbi.2021.110580] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/15/2020] [Accepted: 01/04/2021] [Indexed: 11/25/2022]
Abstract
Oxygenic photoautotrophs are, paradoxically, subject to photoinhibition of their photosynthetic apparatus, in particular one of its major components, the Photosystem II (PSII). Photoinhibition is generalized across species, light conditions and habitats, imposing substantial metabolic costs that lower photosynthetic productivity and constrain the niches of photoautotrophy. As a process driven by light reaching PSII, light attenuation in optically thick samples influences both the actual extent, and the detection, of photoinhibition. Chlorophyll fluorescence is widely used to measure photoinhibition, but fluorescence-based parameters are affected by light attenuation of both downwelling incident radiation traversing the sample to reach PSII, and emitted fluorescence upwelling through the sample. We used modelling, experimental manipulation of within-sample light attenuation, and meta-analysis of published data, to show substantial, differential effects of light attenuation and depth-integration of emitted fluorescence upon measurements of photoinhibition. Numerical simulations and experimental manipulation of light attenuation indicated that PSII photoinactivation tracked using chlorophyll fluorescence can appear to be over three times lower than the inherent cellular susceptibility to photoinactivation, in optically-dense samples such as leaves or biofilms. The meta-analysis of published data showed that this general trend was unknowingly present in the literature, revealing an overall difference of more than five times between optically thick leaves and optically thin cell suspensions. Although fluorescence-based parameters may provide ecophysiologically relevant information for characterizing the sample as a whole, light attenuation and depth integration can vary between samples independently of their intrinsic physiology. They should be used with caution when aiming to quantify in absolute terms inherent photoinhibition-related parameters in optically thick samples.
Collapse
Affiliation(s)
- João Serôdio
- Department of Biology and CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| | - Douglas A Campbell
- Department of Biology, Mount Allison University, Sackville, Canada NB E4L 3G7, Canada
| |
Collapse
|
15
|
Yang S, Shi Y, Zou L, Huang J, Shen L, Wang Y, Guan D, He S. Pepper CaMLO6 Negatively Regulates Ralstonia solanacearum Resistance and Positively Regulates High Temperature and High Humidity Responses. PLANT & CELL PHYSIOLOGY 2020; 61:1223-1238. [PMID: 32343804 DOI: 10.1093/pcp/pcaa052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Plant mildew-resistance locus O (MLO) proteins influence susceptibility to powdery mildew. However, their roles in plant responses to other pathogens and heat stress remain unclear. Here, we showed that CaMLO6, a pepper (Capsicum annuum) member of MLO clade V, is a protein targeted to plasma membrane and probably endoplasmic reticulum. The transcript expression level of CaMLO6 was upregulated in the roots and leaves of pepper plants challenged with high temperature and high humidity (HTHH) and was upregulated in leaves but downregulated in roots of plants infected with the bacterial pathogen Ralstonia solanacearum. CaMLO6 was also directly upregulated by CaWRKY40 upon HTHH but downregulated by CaWRKY40 upon R. solanacearum infection. Virus-induced gene silencing of CaMLO6 significantly decreased pepper HTHH tolerance and R. solanacearum susceptibility. Moreover, CaMLO6 overexpression enhanced the susceptibility of Nicotiana benthamiana and pepper plants to R. solanacearum and their tolerance to HTHH, effects that were associated with the expression of immunity- and thermotolerance-associated marker genes, respectively. These results suggest that CaMLO6 acts as a positive regulator in response to HTHH but a negative regulator in response to R. solanacearum. Moreover, CaMLO6 is transcriptionally affected by R. solanacearum and HTHH; these transcriptional responses are at least partially regulated by CaWRKY40.
Collapse
Affiliation(s)
- Sheng Yang
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Yuanyuan Shi
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Longyun Zou
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Jinfeng Huang
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Lei Shen
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Yuzhu Wang
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Deyi Guan
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Shuilin He
- National Education Ministry Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Key Laboratory of Applied Genetics of Universities in Fujian Province, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
- Agricultural College, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| |
Collapse
|
16
|
|
17
|
Xiong J, Yu L, Zhang Z, Wang Y, Wang W, Yang H, Yan R, Zhu D. Intrinsic kinetic model of photoautotrophic microalgae based on chlorophyll fluorescence analysis. Math Biosci 2019; 315:108234. [PMID: 31330136 DOI: 10.1016/j.mbs.2019.108234] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 07/19/2019] [Accepted: 07/19/2019] [Indexed: 11/28/2022]
Abstract
As photoautotrophic microorganisms, microalgae feature complex mechanisms of photosynthesis and light energy transfer and as such studying their intrinsic growth kinetics is fairly difficult. In this article, the quantum yield of photochemical reaction was introduced in a study of microalgal kinetics to establish an intrinsic kinetic model of photoautotrophic microalgal growth. The blue-green algae Synechococcus sp. PCC7942 was used to verify the kinetic model developed using chlorophyll fluorescence analysis and growth kinetics determination. Results indicate that the kinetic model can realistically reflect the light energy utilization efficiency of microalgae as well as their intrinsic growth kinetic characteristics. The model and method proposed in this article may be utilized in intrinsic kinetics studies of photoautotrophic microorganisms.
Collapse
Affiliation(s)
- Jiawen Xiong
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Linlin Yu
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Zhibin Zhang
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Ya Wang
- Key Laboratory of Bioprocess of Jiangxi Province, Jiangxi Science & Technology Normal University, Nanchang 330013, Jiangxi, China
| | - Weiying Wang
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Huilin Yang
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Riming Yan
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China.
| | - Du Zhu
- Key Laboratory of Protection and Utilization of Subtropic Plant Resources of Jiangxi Province, Jiangxi Normal University, Nanchang 330022, Jiangxi, China; Key Laboratory of Bioprocess of Jiangxi Province, Jiangxi Science & Technology Normal University, Nanchang 330013, Jiangxi, China.
| |
Collapse
|
18
|
Koh HG, Kang NK, Jeon S, Shin SE, Jeong BR, Chang YK. Heterologous synthesis of chlorophyll b in Nannochloropsis salina enhances growth and lipid production by increasing photosynthetic efficiency. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:122. [PMID: 31114631 PMCID: PMC6515666 DOI: 10.1186/s13068-019-1462-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 05/04/2019] [Indexed: 05/16/2023]
Abstract
BACKGROUND Chlorophylls play important roles in photosynthesis, and thus are critical for growth and related metabolic pathways in photosynthetic organisms. They are particularly important in microalgae, emerging as the next generation feedstock for biomass and biofuels. Nannochloropsis are industrial microalgae for these purposes, but are peculiar in that they lack accessory chlorophylls. In addition, the localization of heterologous proteins to the chloroplast of Nannochloropsis has not been fully studied, due to the secondary plastid surrounded by four membranes. This study addressed questions of correct localization and functional benefits of heterologous expression of chlorophyllide a oxygenase from Chlamydomonas (CrCAO) in Nannochloropsis. RESULTS We cloned CrCAO from Chlamydomonas, which catalyzes oxidation of Chla producing Chlb, and overexpressed it in N. salina to reveal effects of the heterologous Chlb for photosynthesis, growth, and lipid production. For correct localization of CrCAO into the secondary plastid in N. salina, we added the signal-recognition sequence and the transit peptide (cloned from an endogenous chloroplast-localized protein) to the N terminus of CrCAO. We obtained two transformants that expressed CrCAO and produced Chlb. They showed improved growth under medium light (90 μmol/m2/s) conditions, and their photosynthetic efficiency was increased compared to WT. They also showed increased expression of certain photosynthetic proteins, accompanied by an increased maximum electron-transfer rate up to 15.8% and quantum yields up to 17%, likely supporting the faster growth. This improved growth resulted in increased biomass production, and more importantly lipid productivity particularly with medium light. CONCLUSIONS We demonstrated beneficial effects of heterologous expression of CrCAO in Chlb-less organism N. salina, where the newly produced Chlb enhanced photosynthesis and growth. Accordingly, transformants showed improved production of biomass and lipids, important traits of microalgae from the industrial perspectives. Our transformants are the first Nannochloropsis cells that produced Chlb in the whole evolutionary path. We also succeeded in delivering a heterologous protein into the secondary plastid for the first time in Nannochloropsis. Taken together, our data showed that manipulation of photosynthetic pigments, including Chlb, can be employed in genetic improvements of microalgae for production of biofuels and other biomaterials.
Collapse
Affiliation(s)
- Hyun Gi Koh
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Nam Kyu Kang
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Seungjib Jeon
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Sung-Eun Shin
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: LG Chem, 188 Munji-ro, Yuseong-gu, Daejeon, 34122 Republic of Korea
| | - Byeong-ryool Jeong
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Yong Keun Chang
- Advanced Biomass R&D Center, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| |
Collapse
|
19
|
Serôdio J, Schmidt W, Frommlet JC, Christa G, Nitschke MR. An LED-based multi-actinic illumination system for the high throughput study of photosynthetic light responses. PeerJ 2018; 6:e5589. [PMID: 30202661 PMCID: PMC6128260 DOI: 10.7717/peerj.5589] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/15/2018] [Indexed: 11/20/2022] Open
Abstract
The responses of photosynthetic organisms to light stress are of interest for both fundamental and applied research. Functional traits related to the photoinhibition, the light-induced loss of photosynthetic efficiency, are particularly interesting as this process is a key limiting factor of photosynthetic productivity in algae and plants. The quantitative characterization of light responses is often time-consuming and calls for cost-effective high throughput approaches that enable the fast screening of multiple samples. Here we present a novel illumination system based on the concept of ‘multi-actinic imaging’ of in vivo chlorophyll fluorescence. The system is based on the combination of an array of individually addressable low power RGBW LEDs and custom-designed well plates, allowing for the independent illumination of 64 samples through the digital manipulation of both exposure duration and light intensity. The illumination system is inexpensive and easily fabricated, based on open source electronics, off-the-shelf components, and 3D-printed parts, and is optimized for imaging of chlorophyll fluorescence. The high-throughput potential of the system is illustrated by assessing the functional diversity in light responses of marine macroalgal species, through the fast and simultaneous determination of kinetic parameters characterizing the response to light stress of multiple samples. Although the presented illumination system was primarily designed for the measurement of phenotypic traits related to photosynthetic activity and photoinhibition, it can be potentially used for a number of alternative applications, including the measurement of chloroplast phototaxis and action spectra, or as the basis for microphotobioreactors.
Collapse
Affiliation(s)
- João Serôdio
- Department of Biology and CESAM-Centre for Environmental and Marine Studies, University of Aveiro, Aveiro, Portugal
| | - William Schmidt
- Department of Biology and CESAM-Centre for Environmental and Marine Studies, University of Aveiro, Aveiro, Portugal
| | - Jörg C Frommlet
- Department of Biology and CESAM-Centre for Environmental and Marine Studies, University of Aveiro, Aveiro, Portugal
| | - Gregor Christa
- Department of Biology and CESAM-Centre for Environmental and Marine Studies, University of Aveiro, Aveiro, Portugal
| | - Matthew R Nitschke
- Department of Biology and CESAM-Centre for Environmental and Marine Studies, University of Aveiro, Aveiro, Portugal
| |
Collapse
|
20
|
Chartrand KM, Szabó M, Sinutok S, Rasheed MA, Ralph PJ. Living at the margins - The response of deep-water seagrasses to light and temperature renders them susceptible to acute impacts. MARINE ENVIRONMENTAL RESEARCH 2018; 136:126-138. [PMID: 29503105 DOI: 10.1016/j.marenvres.2018.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/05/2018] [Accepted: 02/08/2018] [Indexed: 06/08/2023]
Abstract
Seagrasses inhabit environments where light varies at different timescales, nonetheless are acutely sensitive to reductions in light beyond some conditional bounds. Two tropical deep-water seagrasses, Halophila decipiens and Halophila spinulosa, from the Great Barrier Reef were tested for their response to defined light and temperature regimes to identify their growth requirements and potential thresholds of mortality. Species were exposed to two light intensities, saturating (75 μmol photons m-2 s-1) and limiting (25 μmol photons m-2 s-1) light and two temperature treatments (26 °C and 30 °C) over a four-week period. Wavelength-specific parameters of PSII photochemistry were evaluated for seagrass leaves, as well as shoot density, gas exchange, and pigment content. Both species were sustained under saturating light levels (3.2 mol photons m-2 d-1) while limiting light led to decreased shoot density for H. decipiens and H. spinulosa after two and four weeks, respectively. Wavelength-specific photochemistry was also affected under light-limiting treatments for both species while the functional absorption cross section was highly conserved. Photoacclimation and physiological adjustments by either species was not adequate to compensate for reduced irradiance suggesting these plants reside at the margins of their functional limits. As such, relatively short periods of light attenuating events, like dredging or flood plumes, may be detrimental to deep-water seagrass populations.
Collapse
Affiliation(s)
- Kathryn M Chartrand
- Centre for Tropical Water & Aquatic Ecosystem Research, James Cook University, Cairns, Queensland, Australia; Climate Change Cluster, University of Technology Sydney, Broadway, New South Wales, Australia.
| | - Milán Szabó
- Climate Change Cluster, University of Technology Sydney, Broadway, New South Wales, Australia; Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Sutinee Sinutok
- Climate Change Cluster, University of Technology Sydney, Broadway, New South Wales, Australia; Faculty of Environmental Management, Prince of Songkla University, Hat Yai, Thailand; Coastal Oceanography and Climate Change Research Center, Prince of Songkla University, Hat Yai, Thailand
| | - Michael A Rasheed
- Centre for Tropical Water & Aquatic Ecosystem Research, James Cook University, Cairns, Queensland, Australia
| | - Peter J Ralph
- Climate Change Cluster, University of Technology Sydney, Broadway, New South Wales, Australia
| |
Collapse
|
21
|
Sung MG, Han JI, Lee B, Chang YK. Wavelength shift strategy to enhance lipid productivity of Nannochloropsis gaditana. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:70. [PMID: 29560025 PMCID: PMC5858150 DOI: 10.1186/s13068-018-1067-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 03/05/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Microalgae, being a phototroph, grow in the presence of light, and utilizing photons in narrow and specific range of wavelengths. There have been numerous attempts to take advantage of this trait of wavelength-dependent growth for the purpose of increasing biomass productivity. One potential option involves wavelength conversion of sunlight. In the present study, three fluorescent dyes with blue, red, and green emission spectra were employed with the aim of improving sunlight utilization efficiency and thus enhancing biomass and lipid productivity of Nannochloropsis gaditana. RESULTS When DPA and R101 were used to enrich blue and red spectra, biomass productivity of Nannochloropsis gaditana was increased by 35.1 and 40.3%, respectively. The maximum quantum yield values were higher than 0.6 at the early stage of growth for the cultures grown under DPA- and R101-modified solar radiation. Chlorophyll a content was also 57.0 and 32.3% higher than the control at the early growth stage under DPA- and R101-modified solar radiation, respectively. This stimulation of photosynthetic activity at the early growth stage correlated well with rapid growth under DPA- and R101-modified light during the first 4 days of cultivation. Lipid productivity consequently increased by 26.9 (DPA) and 39.4% (R101) after 10 days of cultivation. An immediate effect on lipid induction was observed in cultures under modified light, which exhibited 19.1% improvement in lipid content at the cost of some degree of impaired growth. CONCLUSION Fluorescent dyes with the capability of enriching wavelengths of light favored by the algal photosystem could indeed be an effective means of promoting growth of Nannochloropsis gaditana. This strategy would be particularly powerful for mass cultivation where sunlight is the only economically viable option for illumination.
Collapse
Affiliation(s)
- Min-Gyu Sung
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Jong-In Han
- Department of Civil and Environmental Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Bongsoo Lee
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| | - Yong Keun Chang
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
- Advanced Biomass R&D Center, #2502 Building W1-3, 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 Republic of Korea
| |
Collapse
|
22
|
Havurinne V, Tyystjärvi E. Action Spectrum of Photoinhibition in the Diatom Phaeodactylum tricornutum. PLANT & CELL PHYSIOLOGY 2017; 58:2217-2225. [PMID: 29059446 DOI: 10.1093/pcp/pcx156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 10/15/2017] [Indexed: 05/28/2023]
Abstract
Light-dependent electron transfer is necessary for photosynthesis, but light also damages PSII. Light-induced damage to PSII is called photoinhibition, and the damaging reactions of photoinhibition are still under debate. Diatoms possess an exotic combination of light-harvesting pigments, Chls a/c and fucoxanthin, making them an interesting platform for studying the photoreceptors of photoinhibition. We first confirmed the direct proportionality of photoinhibition to the photon flux density of incident light in the diatom Phaeodactylum tricornutum. Phaeodactylum is known for its efficient non-photochemical quenching, and the effect of this photoprotective mechanism on photoinhibition was tested. Photoinhibition proceeded essentially at the same rate in blue-light-grown Phaeodactylum cells that are capable of non-photochemical quenching and in red-light-grown, non-photochemical quenching-deficient cells. To obtain more insight into how the pigment composition of diatoms affects photoinhibition, we measured the action spectrum of photoinhibition in Phaeodactylum. In visible light, the action spectrum resembled the absorption spectrum of Phaeodactylum, and UV radiation caused much more photoinhibition than visible light. Comparison of the action spectrum of photoinhibition with the absorption spectrum and the excitation spectrum of 77 K PSII fluorescence emission confirmed that photosynthetic pigments are involved in photoinhibition, but the photoinhibitory efficiency of red light is weak, suggesting that the role of light-harvesting pigments as light receptors of photoinhibition is secondary. Finally, we compared photoinhibition in Phaeodactylum with that in other photosynthetic organisms, and our data indicate that the PSII reaction centers of Phaeodactylum are not particularly well protected against the primary damage of photoinhibition.
Collapse
Affiliation(s)
- Vesa Havurinne
- University of Turku, Department of Biochemistry/Molecular Plant Biology, 20014 Turku, Finland
| | - Esa Tyystjärvi
- University of Turku, Department of Biochemistry/Molecular Plant Biology, 20014 Turku, Finland
| |
Collapse
|
23
|
Mechanism of Photodamage of the Oxygen Evolving Mn Cluster of Photosystem II by Excessive Light Energy. Sci Rep 2017; 7:7604. [PMID: 28790352 PMCID: PMC5548768 DOI: 10.1038/s41598-017-07671-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 06/30/2017] [Indexed: 11/28/2022] Open
Abstract
Photodamage to Photosystem II (PSII) has been attributed either to excessive excitation of photosynthetic pigments or by direct of light absorption by Mn4CaO5 cluster. Here we investigated the time course of PSII photodamage and release of Mn in PSII-enriched membranes under high light illumination at 460 nm and 660 nm. We found that the loss of PSII activity, assayed by chlorophyll fluorescence, is faster than release of Mn from the Mn4CaO5 cluster, assayed by EPR. Loss of PSII activity and Mn release was slower during illumination in the presence of exogenous electron acceptors. Recovery of PSII activity was observed, after 30 min of addition of electron donor post illumination. The same behavior was observed under 460 and 660 nm illumination, suggesting stronger correlation between excessive excitation and photodamage compared to direct light absorption by the cluster. A unified model of PSII photodamage that takes into account present and previous literature reports is presented.
Collapse
|
24
|
Serôdio J, Schmidt W, Frankenbach S. A chlorophyll fluorescence-based method for the integrated characterization of the photophysiological response to light stress. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:1123-1135. [PMID: 28069780 DOI: 10.1093/jxb/erw492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This work introduces a new experimental method for the comprehensive description of the physiological responses to light of photosynthetic organisms. It allows the integration in a single experiment of the main established manipulative chlorophyll fluorescence-based protocols. It enables the integrated characterization of the photophysiology of samples regarding photoacclimation state (generating non-sequential light-response curves of effective PSII quantum yield, electron transport rate or non-photochemical quenching), photoprotection capacity (running light stress-recovery experiments, quantifying non-photochemical quenching components) and the operation of photoinactivation and photorepair processes (measuring rate constants of photoinactivation and repair for different light levels and the relative quantum yield of photoinactivation). The new method is based on a previously introduced technique, combining the illumination of a set of replicated samples with spatially separated actinic light beams of different intensity, and the simultaneous measurement of the fluorescence emitted by all samples using an imaging fluorometer. The main novelty described here is the independent manipulation of light intensity and duration of exposure for each sample, and the control of the cumulative light dose applied. The results demonstrate the proof of concept for the method, by comparing the responses of cultures of Chlorella vulgaris acclimated to low and high light regimes, highlighting the mapping of light stress responses over a wide range of light intensity and exposure conditions, and the rapid generation of paired light-response curves of photoinactivation and repair rate constants. This approach represents a chlorophyll fluorescence 'protocol of everything', contributing towards the high throughput characterization of the photophysiology of photosynthetic organisms.
Collapse
Affiliation(s)
- João Serôdio
- Departamento de Biologia andCentro de Estudos do Ambiente e do Mar (CESAM), Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - William Schmidt
- Departamento de Biologia andCentro de Estudos do Ambiente e do Mar (CESAM), Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| | - Silja Frankenbach
- Departamento de Biologia andCentro de Estudos do Ambiente e do Mar (CESAM), Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal
| |
Collapse
|
25
|
He J, Yang W, Qin L, Fan DY, Chow WS. Photoinactivation of Photosystem II in wild-type and chlorophyll b-less barley leaves: which mechanism dominates depends on experimental circumstances. PHOTOSYNTHESIS RESEARCH 2015; 126:399-407. [PMID: 26101037 DOI: 10.1007/s11120-015-0167-0] [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] [Received: 01/03/2015] [Accepted: 06/15/2015] [Indexed: 05/13/2023]
Abstract
Action spectra of photoinactivation of Photosystem II (PS II) in wild-type and chlorophyll b-less barley leaf segments were obtained. Photoinactivation of PS II was monitored by the delivery of electrons from PS II to PS I following single-turnover flashes superimposed on continuous far-red light, the time course of photoinactivation yielding a rate coefficient k i. Susceptibility of PS II to photoinactivation was quantified as the ratio of k i to the moderate irradiance (I) of light at each selected wavelength. k i/I was very much higher in blue light than in red light. The experimental conditions permitted little excess light energy absorbed by chlorophyll (not utilized in photochemical conversion or dissipated in controlled photoprotection) that could lead to photoinactivation of PS II. Therefore, direct absorption of light by Mn in PS II, rather than by chlorophyll, was more likely to have initiated the much more severe photoinactivation in blue light than in red light. Mutant leaves were ca. 1.5-fold more susceptible to photoinactivation than the wild type. Neither the excess-energy mechanism nor the Mn mechanism can explain this difference. Instead, the much lower chlorophyll content of mutant leaves could have exerted an exacerbating effect, possibly partly due to less mutual shading of chloroplasts in the mutant leaves. In general, which mechanism dominates depends on the experimental conditions.
Collapse
Affiliation(s)
- Jie He
- Natural Sciences & Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore, 637616, Singapore
| | - Wenquan Yang
- College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Division of Plant Science, Research School of Biology, The Australian National University, 46 Biology Place, Canberra, ACT, 2601, Australia
| | - Lin Qin
- Natural Sciences & Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore, 637616, Singapore
| | - Da-Yong Fan
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
- Division of Plant Science, Research School of Biology, The Australian National University, 46 Biology Place, Canberra, ACT, 2601, Australia
| | - Wah Soon Chow
- Division of Plant Science, Research School of Biology, The Australian National University, 46 Biology Place, Canberra, ACT, 2601, Australia.
| |
Collapse
|
26
|
Zavafer A, Cheah MH, Hillier W, Chow WS, Takahashi S. Photodamage to the oxygen evolving complex of photosystem II by visible light. Sci Rep 2015; 5:16363. [PMID: 26560020 PMCID: PMC4642293 DOI: 10.1038/srep16363] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/06/2015] [Indexed: 11/10/2022] Open
Abstract
Light damages photosynthetic machinery, primarily photosystem II (PSII), and it results in photoinhibition. A new photodamage model, the two-step photodamage model, suggests that photodamage to PSII initially occurs at the oxygen evolving complex (OEC) by light energy absorbed by manganese and that the PSII reaction center is subsequently damaged by light energy absorbed by photosynthetic pigments due to the limitation of electrons to the PSII reaction center. However, it is still uncertain whether this model is applicable to photodamage to PSII under visible light as manganese absorbs visible light only weakly. In the present study, we identified the initial site of photodamage to PSII upon illumination of visible light using PSII membrane fragments isolated from spinach leaves. When PSII samples were exposed to visible light in the presence of an exogenous electron acceptor, both PSII total activity and the PSII reaction centre activity declined due to photodamage. The supplemental addition of an electron donor to the PSII reaction centre alleviated the decline of the reaction centre activity but not the PSII total activity upon the light exposure. Our results demonstrate that visible light damages OEC prior to photodamage to the PSII reaction center, consistent with two-step photodamage model.
Collapse
Affiliation(s)
- Alonso Zavafer
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2601 Australia
| | - Mun Hon Cheah
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2601 Australia
| | - Warwick Hillier
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2601 Australia
| | - Wah Soon Chow
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2601 Australia
| | - Shunichi Takahashi
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2601 Australia
| |
Collapse
|
27
|
Zavafer A, Chow WS, Cheah MH. The action spectrum of Photosystem II photoinactivation in visible light. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 152:247-60. [PMID: 26298696 DOI: 10.1016/j.jphotobiol.2015.08.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/23/2015] [Accepted: 08/10/2015] [Indexed: 12/25/2022]
Abstract
Photosynthesis is always accompanied by light induced damage to the Photosystem II (PSII) which is compensated by its subsequent repair. Photoinhibition of PSII is a complex process, balancing between photoinactivation, protective and repair mechanisms. Current understanding of photoinactivation is limited with competing hypotheses where the photosensitiser is either photosynthetic pigments or the Mn4CaO5 cluster itself, with little consensus on the mechanisms and consequences of PSII photoinactivation. The mechanism of photoinactivation should be reflected in the action spectrum of PSII photoinactivation, but there is a great diversity of the action spectra reported thus far. The only consensus is that PSII photoinactivation is greatest in the UV region of the electromagnetic spectrum. In this review, the authors revisit the methods, technical constraints and the different action spectra of PSII photoinactivation reported to date and compare them against the diverse mechanisms proposed. Upon critical examination of the reported action spectra, a hybrid mechanism of photoinactivation, sensitised by both photosynthetic pigments and the Mn4CaO5 appears to be the most plausible rationalisation.
Collapse
Affiliation(s)
- Alonso Zavafer
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 2601, Australia
| | - Wah Soon Chow
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 2601, Australia
| | - Mun Hon Cheah
- Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 2601, Australia.
| |
Collapse
|
28
|
Klughammer C, Schreiber U. Apparent PS II absorption cross-section and estimation of mean PAR in optically thin and dense suspensions of Chlorella. PHOTOSYNTHESIS RESEARCH 2015; 123:77-92. [PMID: 25218266 DOI: 10.1007/s11120-014-0040-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 09/03/2014] [Indexed: 05/12/2023]
Abstract
Theoretical prediction of effective mean PAR in optically dense samples is complicated by various optical effects, including light scattering and reflections. Direct information on the mean rate of photon absorption by PS II is provided by the kinetics of the fluorescence rise induced upon onset of strong actinic illumination (O-I1 rise). A recently introduced kinetic multi-color PAM fluorometer was applied to study the relationship between initial slope and cell density in the relatively simple model system of suspensions of Chlorella. Use of a curve fitting routine was made which was originally developed for assessment of the wavelength-dependent absorption cross-section of PS II, σ II(λ), in dilute suspensions. The model underlying analysis of the O-I1 rise kinetics is outlined and data on the relationship between fitted values of σ II(λ) and PAR in dilute samples are presented. With increasing cell density, lowering of apparent cross-section, <σ>(λ), with respect to σ II(λ), relates to a decrease of effective mean PAR, <PAR>(λ), relative to incident PAR(λ). When ML and AL are applied in the same direction, the decline of <σ>(λ)/σ II(λ) with increasing optical density is less steep than that of the theoretically predicted <PAR>(λ)/PAR(λ). It approaches a value of 0.5 when the same colors of ML and AL are used, in agreement with theory. These observations open the way for estimating mean PAR in optically dense samples via measurements of <σ>(λ)/σ II(λ)).
Collapse
Affiliation(s)
- Christof Klughammer
- Julius-von-Sachs Institut für Biowissenschaften, Universität Würzburg, Julius-von-Sachs Platz 2, 97082, Würzburg, Germany
| | | |
Collapse
|
29
|
Tamburic B, Szabó M, Tran NAT, Larkum AWD, Suggett DJ, Ralph PJ. Action spectra of oxygen production and chlorophyll a fluorescence in the green microalga Nannochloropsis oculata. BIORESOURCE TECHNOLOGY 2014; 169:320-327. [PMID: 25063974 DOI: 10.1016/j.biortech.2014.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 06/03/2023]
Abstract
The first complete action spectrum of oxygen evolution and chlorophyll a fluorescence was measured for the biofuel candidate alga Nannochloropsis oculata. A novel analytical procedure was used to generate a representative and reproducible action spectrum for microalgal cultures. The action spectrum was measured at 14 discrete wavelengths across the visible spectrum, at an equivalent photon flux density of 60 μmol photon sm(-2) s(-1). Blue light (∼ 414 nm) was absorbed more efficiently and directed to photosystem II more effectively than red light (∼ 679 nm) at light intensities below the photosaturation limit. Conversion of absorbed photons into photosynthetic oxygen evolution was maximised at 625 nm; however, this maximum is unstable since neighbouring wavelengths (646 nm) resulted in the lowest photosystem II operating efficiency. Identifying the wavelength-dependence of photosynthesis has clear implications to optimising growth efficiency and hence important economic implications to the algal biofuels and bioproducts industries.
Collapse
Affiliation(s)
- Bojan Tamburic
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia.
| | - Milán Szabó
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia
| | - Nhan-An T Tran
- School of the Environment, Faculty of Science, University of Technology, Sydney, Broadway NSW 2007, Australia
| | - Anthony W D Larkum
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia
| | - David J Suggett
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia
| | - Peter J Ralph
- Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia; School of the Environment, Faculty of Science, University of Technology, Sydney, Broadway NSW 2007, Australia
| |
Collapse
|
30
|
Szabó M, Wangpraseurt D, Tamburic B, Larkum AWD, Schreiber U, Suggett DJ, Kühl M, Ralph PJ. Effective light absorption and absolute electron transport rates in the coral Pocillopora damicornis. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2014; 83:159-167. [PMID: 25146689 DOI: 10.1016/j.plaphy.2014.07.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 07/20/2014] [Indexed: 06/03/2023]
Abstract
Pulse Amplitude Modulation (PAM) fluorometry has been widely used to estimate the relative photosynthetic efficiency of corals. However, both the optical properties of intact corals as well as past technical constrains to PAM fluorometers have prevented calculations of the electron turnover rate of PSII. We used a new Multi-colour PAM (MC-PAM) in parallel with light microsensors to determine for the first time the wavelength-specific effective absorption cross-section of PSII photochemistry, σII(λ), and thus PAM-based absolute electron transport rates of the coral photosymbiont Symbiodinium both in culture and in hospite in the coral Pocillopora damicornis. In both cases, σII of Symbiodinium was highest in the blue spectral region and showed a progressive decrease towards red wavelengths. Absolute values for σII at 440 nm were up to 1.5-times higher in culture than in hospite. Scalar irradiance within the living coral tissue was reduced by 20% in the blue when compared to the incident downwelling irradiance. Absolute electron transport rates of P. damicornis at 440 nm revealed a maximum PSII turnover rate of ca. 250 electrons PSII(-1) s(-1), consistent with one PSII turnover for every 4 photons absorbed by PSII; this likely reflects the limiting steps in electron transfer between PSII and PSI. Our results show that optical properties of the coral host strongly affect light use efficiency of Symbiodinium. Therefore, relative electron transport rates do not reflect the productivity rates (or indeed how the photosynthesis-light response is parameterised). Here we provide a non-invasive approach to estimate absolute electron transport rates in corals.
Collapse
Affiliation(s)
- Milán Szabó
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia.
| | - Daniel Wangpraseurt
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia
| | - Bojan Tamburic
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia
| | - Anthony W D Larkum
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia
| | - Ulrich Schreiber
- Julius-von-Sachs Institut für Biowissenschaften, Lehrstuhl Botanik I, Universität Würzburg, Germany
| | - David J Suggett
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia
| | - Michael Kühl
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia; Marine Biological Section, Department of Biology, University of Copenhagen, DK-3000 Helsingør, Denmark
| | - Peter J Ralph
- Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, Broadway 2007, NSW, Australia
| |
Collapse
|
31
|
Szabó M, Parker K, Guruprasad S, Kuzhiumparambil U, Lilley RM, Tamburic B, Schliep M, Larkum AWD, Schreiber U, Raven JA, Ralph PJ. Photosynthetic acclimation of Nannochloropsis oculata investigated by multi-wavelength chlorophyll fluorescence analysis. BIORESOURCE TECHNOLOGY 2014; 167:521-529. [PMID: 25016367 DOI: 10.1016/j.biortech.2014.06.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/11/2014] [Accepted: 06/13/2014] [Indexed: 06/03/2023]
Abstract
Multi-wavelength chlorophyll fluorescence analysis was utilised to examine the photosynthetic efficiency of the biofuel-producing alga Nannochloropsis oculata, grown under two light regimes; low (LL) and high (HL) irradiance levels. Wavelength dependency was evident in the functional absorption cross-section of Photosystem II (σII(λ)), absolute electron transfer rates (ETR(II)), and non-photochemical quenching (NPQ) of chlorophyll fluorescence in both HL and LL cells. While σII(λ) was not significantly different between the two growth conditions, HL cells upregulated ETR(II) 1.6-1.8-fold compared to LL cells, most significantly in the wavelength range of 440-540 nm. This indicates preferential utilisation of blue-green light, a highly relevant spectral region for visible light in algal pond conditions. Under these conditions, the HL cells accumulated saturated fatty acids, whereas polyunsaturated fatty acids were more abundant in LL cells. This knowledge is of importance for the use of N. oculata for fatty acid production in the biofuel industry.
Collapse
Affiliation(s)
- Milán Szabó
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia.
| | - Kieran Parker
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Supriya Guruprasad
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | | | - Ross McC Lilley
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Bojan Tamburic
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Martin Schliep
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Anthony W D Larkum
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Ulrich Schreiber
- Julius-von-Sachs Institut für Biowissenschaften, Universität Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany
| | - John A Raven
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Peter J Ralph
- Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, Broadway, NSW 2007, Australia
| |
Collapse
|
32
|
Laisk A, Oja V, Eichelmann H, Dall'Osto L. Action spectra of photosystems II and I and quantum yield of photosynthesis in leaves in State 1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1837:315-25. [PMID: 24333386 DOI: 10.1016/j.bbabio.2013.12.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 10/30/2013] [Accepted: 12/03/2013] [Indexed: 11/30/2022]
Abstract
The spectral global quantum yield (YII, electrons/photons absorbed) of photosystem II (PSII) was measured in sunflower leaves in State 1 using monochromatic light. The global quantum yield of PSI (YI) was measured using low-intensity monochromatic light flashes and the associated transmittance change at 810nm. The 810-nm signal change was calibrated based on the number of electrons generated by PSII during the flash (4·O2 evolution) which arrived at the PSI donor side after a delay of 2ms. The intrinsic quantum yield of PSI (yI, electrons per photon absorbed by PSI) was measured at 712nm, where photon absorption by PSII was small. The results were used to resolve the individual spectra of the excitation partitioning coefficients between PSI (aI) and PSII (aII) in leaves. For comparison, pigment-protein complexes for PSII and PSI were isolated, separated by sucrose density ultracentrifugation, and their optical density was measured. A good correlation was obtained for the spectral excitation partitioning coefficients measured by these different methods. The intrinsic yield of PSI was high (yI=0.88), but it absorbed only about 1/3 of quanta; consequently, about 2/3 of quanta were absorbed by PSII, but processed with the low intrinsic yield yII=0.63. In PSII, the quantum yield of charge separation was 0.89 as detected by variable fluorescence Fv/Fm, but 29% of separated charges recombined (Laisk A, Eichelmann H and Oja V, Photosynth. Res. 113, 145-155). At wavelengths less than 580nm about 30% of excitation is absorbed by pigments poorly connected to either photosystem, most likely carotenoids bound in pigment-protein complexes.
Collapse
Affiliation(s)
- Agu Laisk
- Tartu Ülikooli Molekulaar- ja Rakubioloogia Instituut, Riia tn. 23, Tartu 51010, Estonia.
| | - Vello Oja
- Tartu Ülikooli Molekulaar- ja Rakubioloogia Instituut, Riia tn. 23, Tartu 51010, Estonia
| | - Hillar Eichelmann
- Tartu Ülikooli Molekulaar- ja Rakubioloogia Instituut, Riia tn. 23, Tartu 51010, Estonia
| | - Luca Dall'Osto
- Università di Verona, Dipartimento di Biotecnologie, Strada Le Grazie, 15 37135 Verona, Italy
| |
Collapse
|
33
|
Raven JA, Beardall J, Larkum AWD, Sánchez-Baracaldo P. Interactions of photosynthesis with genome size and function. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120264. [PMID: 23754816 DOI: 10.1098/rstb.2012.0264] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Photolithotrophs are divided between those that use water as their electron donor (Cyanobacteria and the photosynthetic eukaryotes) and those that use a different electron donor (the anoxygenic photolithotrophs, all of them Bacteria). Photolithotrophs with the most reduced genomes have more genes than do the corresponding chemoorganotrophs, and the fastest-growing photolithotrophs have significantly lower specific growth rates than the fastest-growing chemoorganotrophs. Slower growth results from diversion of resources into the photosynthetic apparatus, which accounts for about half of the cell protein. There are inherent dangers in (especially oxygenic) photosynthesis, including the formation of reactive oxygen species (ROS) and blue light sensitivity of the water spitting apparatus. The extent to which photolithotrophs incur greater DNA damage and repair, and faster protein turnover with increased rRNA requirement, needs further investigation. A related source of environmental damage is ultraviolet B (UVB) radiation (280-320 nm), whose flux at the Earth's surface decreased as oxygen (and ozone) increased in the atmosphere. This oxygenation led to the requirements of defence against ROS, and decreasing availability to organisms of combined (non-dinitrogen) nitrogen and ferrous iron, and (indirectly) phosphorus, in the oxygenated biosphere. Differential codon usage in the genome and, especially, the proteome can lead to economies in the use of potentially growth-limiting elements.
Collapse
Affiliation(s)
- John A Raven
- School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
| | | | | | | |
Collapse
|
34
|
Campbell DA, Hossain Z, Cockshutt AM, Zhaxybayeva O, Wu H, Li G. Photosystem II protein clearance and FtsH function in the diatom Thalassiosira pseudonana. PHOTOSYNTHESIS RESEARCH 2013; 115:43-54. [PMID: 23504483 DOI: 10.1007/s11120-013-9809-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 03/01/2013] [Indexed: 05/13/2023]
Abstract
All oxygenic photoautotrophs suffer photoinactivation of their Photosystem II complexes, at a rate driven by the instantaneous light level. To maintain photosynthesis, PsbA subunits are proteolytically removed from photoinactivated Photosystem II complexes, primarily by a membrane-bound FtsH protease. Diatoms thrive in environments with fluctuating light, such as coastal regions, in part because they enjoy a low susceptibility to photoinactivation of Photosystem II. In a coastal strain of the diatom Thalassiosira pseudonana growing across a range of light levels, active Photosystem II represents only about 42 % of the total Photosystem II protein, with the remainder attributable to photoinactivated Photosystem II awaiting recycling. The rate constant for removal of PsbA protein increases with growth light, in parallel with an increasing content of the FtsH protease relative to the substrate PsbA. An offshore strain of Thalassiosira pseudonana, originating from a more stable light environment, had a lower content of FtsH and slower rate constants for removal of PsbA. We used this data to generate the first estimates for in vivo proteolytic degradation of photoinactivated PsbA per FtsH6 protease, at ~3.9 × 10(-2) s(-1), which proved consistent across growth lights and across the onshore and offshore strains.
Collapse
Affiliation(s)
- Douglas A Campbell
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville, NB E4L 1G7, Canada.
| | | | | | | | | | | |
Collapse
|