Photosynthesis Research最新文献

{"title":"Salt and heat stress enhances hydrogen production in cyanobacteria.","authors":"Panayiotis-Ilias Broussos, George E Romanos, Kostas Stamatakis","doi":"10.1007/s11120-024-01098-2","DOIUrl":"10.1007/s11120-024-01098-2","url":null,"abstract":"<p><p>Cyanobacteria are among the most suitable organisms for the capture of excessive amounts of CO₂ and can be grown in extreme environments. In our research we use the single-celled freshwater cyanobacteria Synechococcus elongatus PCC7942 PAMCOD strain and Synechocystis sp. PCC6714 for the production of carbohydrates and hydrogen. PAMCOD strain and Synechocystis sp. PCC6714 synthesize sucrose when exposed to salinity stress, as their main compatible osmolyte. We examined the cell proliferation rate and the sucrose accumulation in those two different strains of cyanobacteria under salt (0.4 M NaCl) and heat stress (35 ⁰C) conditions. The intracellular sucrose (mol sucrose content per Chl a) was found to increase by 50% and 108% in PAMCOD strain and Synechocystis sp. PCC6714 cells, respectively. As previously reported, PAMCOD strain has the ability to produce hydrogen through the process of dark anaerobic fermentation (Vayenos D, Romanos GE, Papageorgiou GC, Stamatakis K (2020) Photosynth Res 146, 235-245). In the present study, we demonstrate that Synechocystis sp. PCC6714 has also this ability. We further examined the optimal conditions during the dark fermentation of PAMCOD and Synechocystis sp. PCC6714 regarding H₂ formation, increasing the PAMCOD H₂ productivity from 2 nmol H₂ h^- 1 mol Chl a^- 1 to 23 nmol H₂ h^- 1 mol Chl a^- 1. Moreover, after the dark fermentation, the cells demonstrated proliferation in both double BG-11 and BG-11 medium enriched in NaNO₃, thus showing the sustainability of the procedure.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":" ","pages":"117-125"},"PeriodicalIF":2.9,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140318908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indirect interactions involving the PsbM or PsbT subunits and the PsbO, PsbU and PsbV proteins stabilize assembly and activity of Photosystem II in Synechocystis sp. PCC 6803.","authors":"Faiza Arshad, Julian J Eaton-Rye","doi":"10.1007/s11120-024-01091-9","DOIUrl":"10.1007/s11120-024-01091-9","url":null,"abstract":"<p><p>The low-molecular-weight PsbM and PsbT proteins of Photosystem II (PS II) are both located at the monomer-monomer interface of the mature PS II dimer. Since the extrinsic proteins are associated with the final step of assembly of an active PS II monomer and, in the case of PsbO, are known to impact the stability of the PS II dimer, we have investigated the potential cooperativity between the PsbM and PsbT subunits and the PsbO, PsbU and PsbV extrinsic proteins. Blue-native polyacrylamide electrophoresis and western blotting detected stable PS II monomers in the ∆PsbM:∆PsbO and ∆PsbT:∆PsbO mutants that retained sufficient oxygen-evolving activity to support reduced photoautotrophic growth. In contrast, the ∆PsbM:∆PsbU and ∆PsbT:∆PsbU mutants assembled dimeric PS II at levels comparable to wild type and supported photoautotrophic growth at rates similar to those obtained with the corresponding ∆PsbM and ∆PsbT cells. Removal of PsbV was more detrimental than removal of PsbO. Only limited levels of dimeric PS II were observed in the ∆PsbM:∆PsbV mutant and the overall reduced level of assembled PS II in this mutant resulted in diminished rates of photoautotrophic growth and PS II activity below those obtained in the ∆PsbM:∆PsbO and ∆PsbT:∆PsbO strains. In addition, the ∆PsbT:∆PsbV mutant did not assemble active PS II centers although inactive monomers could be detected. The inability of the ∆PsbT:∆PsbV mutant to grow photoautotrophically, or to evolve oxygen, suggested a stable oxygen-evolving complex could not assemble in this mutant.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":" ","pages":"61-75"},"PeriodicalIF":2.9,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11108944/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140137114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of different light conditions on morphological, anatomical, photosynthetic and biochemical parameters of Cypripedium macranthos Sw.","authors":"Yuqing Zhang, Wei Liu, Xi Lu, Shuang Li, Ying Li, Yuze Shan, Shizhuo Wang, Yunwei Zhou, Lifei Chen","doi":"10.1007/s11120-024-01100-x","DOIUrl":"10.1007/s11120-024-01100-x","url":null,"abstract":"<p><p>In this study, the morphological (plant height, leaf length and width, stem diameter and leaf number), anatomical (epidermal cell density and thickness, Stomatal length and width), photosynthetic (net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO₂ concentration, relative humidity, leaf temperature and chlorophyll fluorescence parameters) and biochemical parameters (the content of soluble sugar, soluble protein, proline, malondialdehyde and electrical conductivity) of Cypripedium macranthos Sw. in Changbai Mountain were determined under different light conditions (L10, L30, L50, L100). The results showed that morphological values including plant height, leaf area, stem diameter and leaf number of C. macranthos were smaller under the condition of full light at L100. The epidermal cell density and epidermal thickness of C. macranthos were the highest under L30 and L50 treatments, respectively. It had the highest net photosynthetic rate (Pn) and chlorophyll content under L50 treatment. Meanwhile, correlation analysis indicated that photosynthetically active radiation (PAR) and water use efficiency (WUE) were the main factors influencing Pn. C. macranthos accumulated more soluble sugars and soluble proteins under L100 treatment, while the degree of membrane peroxidation was the highest and the plant was severely damaged. In summary, the adaptability of C. macranthos to light conditions is ranked as follows L50 > L30 > L10 > L100. Appropriate light conditions for C. macranthos are 30%-50% of full light, which should be taken into account in protection and cultivation.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":" ","pages":"97-109"},"PeriodicalIF":3.7,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140857502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accurate photosynthetic parameter estimation at low stomatal conductance: effects of cuticular conductance and instrumental noise.","authors":"Syed Bilal Hussain, Joseph Stinziano, Myrtho O Pierre, Christopher Vincent","doi":"10.1007/s11120-024-01092-8","DOIUrl":"10.1007/s11120-024-01092-8","url":null,"abstract":"<p><p>Accurate estimation of photosynthetic parameters is essential for understanding plant physiological limitations and responses to environmental factors from the leaf to the global scale. Gas exchange is a useful tool to measure responses of net CO₂ assimilation (A) to internal CO₂ concentration (C_i), a necessary step in estimating photosynthetic parameters including the maximum rate of carboxylation (V_cmax) and the electron transport rate (J_max). However, species and environmental conditions of low stomatal conductance (g_sw) reduce the signal-to-noise ratio of gas exchange, challenging estimations of C_i. Previous works showed that not considering cuticular conductance to water (g_cw) can lead to significant errors in estimating C_i, because it has a different effect on total conductance to CO₂ (g_tc) than does g_sw. Here we present a systematic assessment of the need for incorporating g_cw into C_i estimates. In this study we modeled the effect of g_cw and of instrumental noise and quantified these effects on photosynthetic parameters in the cases of four species with varying g_sw and g_cw, measured using steady-state and constant ramping techniques, like the rapid A/C_i response method. We show that not accounting for g_cw quantitatively influences C_i and the resulting V_cmax and J_max, particularly when g_cw exceeds 7% of the total conductance to water. The influence of g_cw was not limited to low g_sw species, highlighting the importance of species-specific knowledge before assessing A/C_i curves. Furthermore, at low g_sw instrumental noise can affect C_i estimation, but the effect of instrumental noise can be minimized using constant-ramping rather than steady-state techniques. By incorporating these considerations, more precise measurements and interpretations of photosynthetic parameters can be obtained in a broader range of species and environmental conditions.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":" ","pages":"111-124"},"PeriodicalIF":3.7,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11108943/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140850962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remembering Jan Amesz (1934–2001): a great gentleman, a major discoverer, and an internationally renowned biophysicist of both oxygenic and anoxygenic photosynthesisa","authors":"Govindjee Govindjee, Bas Amesz, Győző Garab, Alexandrina Stirbet","doi":"10.1007/s11120-024-01102-9","DOIUrl":"https://doi.org/10.1007/s11120-024-01102-9","url":null,"abstract":"<p>We present here the research contributions of Jan Amesz (1934–2001) on deciphering the details of the early physico-chemical steps in oxygenic photosynthesis in plants, algae and cyanobacteria, as well as in anoxygenic photosynthesis in purple, green, and heliobacteria. His research included light absorption and the mechanism of excitation energy transfer, primary photochemistry, and electron transfer steps until the reduction of pyridine nucleotides. Among his many discoveries, we emphasize his 1961 proof, with L. N. M. Duysens, of the “series scheme” of oxygenic photosynthesis, through antagonistic effects of Light I and II on the redox state of cytochrome <i>f</i>. Further, we highlight the following research on oxygenic photosynthesis: the experimental direct proof that plastoquinone and plastocyanin function at their respective places in the Z-scheme. In addition, Amesz’s major contributions were in unraveling the mechanism of excitation energy transfer and electron transport steps in anoxygenic photosynthetic bacteria (purple, green and heliobacteria). Before we present his research, focusing on his key discoveries, we provide a glimpse of his personal life. We end this Tribute with reminiscences from three of his former doctoral students (Sigi Neerken; Hjalmar Pernentier, and Frank Kleinherenbrink) and from several scientists (Suleyman Allakhverdiev; Robert Blankenship; Richard Cogdell) including two of the authors (G. Garab and A. Stirbet) of this Tribute.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":"18 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140842084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The synergy between the PscC subunits for electron transfer to the P840 special pair in Chlorobaculum tepidum","authors":"Alexandros Lyratzakis, Vangelis Daskalakis, Hao Xie, Georgios Tsiotis","doi":"10.1007/s11120-024-01093-7","DOIUrl":"https://doi.org/10.1007/s11120-024-01093-7","url":null,"abstract":"<p>The primary photochemical reaction of photosynthesis in green sulfur bacteria occurs in the homodimer PscA core proteins by a special chlorophyll pair. The light induced excited state of the special pair producing P₈₄₀⁺ is rapidly reduced by electron transfer from one of the two PscC subunits. Molecular dynamics (MD) simulations are combined with bioinformatic tools herein to provide structural and dynamic insight into the complex between the two PscA core proteins and the two PscC subunits. The microscopic dynamic model involves extensive sampling at atomic resolution and at a cumulative time-scale of 22µs and reveals well defined protein–protein interactions. The membrane complex is composed of the two PscA and the two PscC subunits and macroscopic connections are revealed within a putative electron transfer pathway from the PscC subunit to the special pair P₈₄₀ located within the PscA subunits. Our results provide a structural basis for understanding the electron transport to the homodimer RC of the green sulfur bacteria. The MD based approach can provide the basis to further probe the PscA-PscC complex dynamics and observe electron transfer therein at the quantum level. Furthermore, the transmembrane helices of the different PscC subunits exert distinct dynamics in the complex.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":"41 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140584122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stimulated X-ray emission spectroscopy","authors":"Uwe Bergmann","doi":"10.1007/s11120-024-01080-y","DOIUrl":"https://doi.org/10.1007/s11120-024-01080-y","url":null,"abstract":"<p>We describe an emerging hard X-ray spectroscopy technique, stimulated X-ray emission spectroscopy (S-XES). S-XES has the potential to characterize the electronic structure of 3d transition metal complexes with spectral information currently not reachable and might lead to the development of new ultrafast X-ray sources with properties beyond the state of the art. S-XES has become possible with the emergence of X-ray free-electron lasers (XFELs) that provide intense femtosecond X-ray pulses that can be employed to generate a population inversion of core–hole excited states resulting in stimulated X-ray emission. We describe the instrumentation, the various types of S-XES, the potential applications, the experimental challenges, and the feasibility of applying S-XES to characterize dilute systems, including the Mn₄Ca cluster in the oxygen evolving complex of photosystem II.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":"50 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140584257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From leaf to multiscale models of photosynthesis: applications and challenges for crop improvement","authors":"Alexandrina Stirbet, Ya Guo, Dušan Lazár, Govindjee Govindjee","doi":"10.1007/s11120-024-01083-9","DOIUrl":"https://doi.org/10.1007/s11120-024-01083-9","url":null,"abstract":"<p>To keep up with the growth of human population and to circumvent deleterious effects of global climate change, it is essential to enhance crop yield to achieve higher production. Here we review mathematical models of oxygenic photosynthesis that are extensively used, and discuss in depth a subset that accounts for diverse approaches providing solutions to our objective. These include models (1) to study different ways to enhance photosynthesis, such as fine-tuning antenna size, photoprotection and electron transport; (2) to bioengineer carbon metabolism; and (3) to evaluate the interactions between the process of photosynthesis and the seasonal crop dynamics, or those that have included statistical whole-genome prediction methods to quantify the impact of photosynthesis traits on the improvement of crop yield. We conclude by emphasizing that the results obtained in these studies clearly demonstrate that mathematical modelling is a key tool to examine different approaches to improve photosynthesis for better productivity, while effective multiscale crop models, especially those that also include remote sensing data, are indispensable to verify different strategies to obtain maximized crop yields.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":"161 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140584021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling large charge transfer character of PSII in an iron-deficient cyanobacterial membrane: A Stark fluorescence spectroscopy study","authors":"Anjue Mane Ara, Sandrine D’Haene, Rienk van Grondelle, Md. Wahadoszamen","doi":"10.1007/s11120-024-01099-1","DOIUrl":"https://doi.org/10.1007/s11120-024-01099-1","url":null,"abstract":"<p>In this work, we applied Stark fluorescence spectroscopy to an iron-stressed cyanobacterial membrane to reveal key insights about the electronic structures and excited state dynamics of the two important pigment-protein complexes, IsiA and PSII, both of which prevail simultaneously within the membrane during iron deficiency and whose fluorescence spectra are highly overlapped and hence often hardly resolved by conventional fluorescence spectroscopy. Thanks to the ability of Stark fluorescence spectroscopy, the fluorescence signatures of the two complexes could be plausibly recognized and disentangled. The systematic analysis of the SF spectra, carried out by employing standard Liptay formalism with a realistic spectral deconvolution protocol, revealed that the IsiA in an intact membrane retains almost identical excited state electronic structures and dynamics as compared to the isolated IsiA we reported in our earlier study. Moreover, the analysis uncovered that the excited state of the PSII subunit of the intact membrane possesses a significantly large CT character. The observed notably large magnitude of the excited state CT character may signify the supplementary role of PSII in regulative energy dissipation during iron deficiency.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":"119 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140584268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ApcE plays an important role in light-induced excitation energy dissipation in the Synechocystis PCC6803 phycobilisomes.","authors":"Gonfa Tesfaye Assefa, Joshua L Botha, Bertus van Heerden, Farooq Kyeyune, Tjaart P J Krüger, Michal Gwizdala","doi":"10.1007/s11120-024-01078-6","DOIUrl":"10.1007/s11120-024-01078-6","url":null,"abstract":"<p><p>Phycobilisomes (PBs) play an important role in cyanobacterial photosynthesis. They capture light and transfer excitation energy to the photosynthetic reaction centres. PBs are also central to some photoprotective and photoregulatory mechanisms that help sustain photosynthesis under non-optimal conditions. Amongst the mechanisms involved in excitation energy dissipation that are activated in response to excessive illumination is a recently discovered light-induced mechanism that is intrinsic to PBs and has been the least studied. Here, we used single-molecule spectroscopy and developed robust data analysis methods to explore the role of a terminal emitter subunit, ApcE, in this intrinsic, light-induced mechanism. We isolated the PBs from WT Synechocystis PCC 6803 as well as from the ApcE-C190S mutant of this strain and compared the dynamics of their fluorescence emission. PBs isolated from the mutant (i.e., ApcE-C190S-PBs), despite not binding some of the red-shifted pigments in the complex, showed similar global emission dynamics to WT-PBs. However, a detailed analysis of dynamics in the core revealed that the ApcE-C190S-PBs are less likely than WT-PBs to enter quenched states under illumination but still fully capable of doing so. This result points to an important but not exclusive role of the ApcE pigments in the light-induced intrinsic excitation energy dissipation mechanism in PBs.</p>","PeriodicalId":20130,"journal":{"name":"Photosynthesis Research","volume":" ","pages":"17-29"},"PeriodicalIF":3.7,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11006782/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139973059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}