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Prechsl UE, Mejia-Aguilar A, Cullinan CB. In vivo spectroscopy and machine learning for the early detection and classification of different stresses in apple trees. Sci Rep 2023; 13:15857. [PMID: 37739998 PMCID: PMC10517117 DOI: 10.1038/s41598-023-42428-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 09/10/2023] [Indexed: 09/24/2023] Open
Abstract
The use of in vivo spectroscopy to detect plant stress in its early stages has the potential to enhance food safety and reduce the need for plant protection products. However, differentiating between various stress types before symptoms appear remains poorly studied. In this study, we investigated the potential of Vis-NIR spectroscopy to differentiate between stress types in apple trees (Malus x domestica Borkh.) exposed to apple scab, waterlogging, and herbicides in a greenhouse. Using a spectroradiometer, we collected spectral signatures of leaves still attached to the tree and utilized machine learning techniques to develop predictive models for detecting stress presence and classifying stress type as early as 1-5 days after exposure. Our findings suggest that changes in spectral reflectance at multiple regions accurately differentiate various types of plant stress on apple trees. Our models were highly accurate (accuracies between 0.94 and 1) when detecting the general presence of stress at an early stage. The wavelengths important for classification relate to photosynthesis via pigment functioning (684 nm) and leaf water (~ 1800-1900 nm), which may be associated with altered gas exchange as a short-term stress response. Overall, our study demonstrates the potential of spectral technology and machine learning for early diagnosis of plant stress, which could lead to reduced environmental burden through optimizing resource utilization in agriculture.
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Affiliation(s)
- Ulrich E Prechsl
- Laimburg Research Centre, Laimburg 6, 39040, Auer, South Tyrol, Italy.
| | | | - Cameron B Cullinan
- Laimburg Research Centre, Laimburg 6, 39040, Auer, South Tyrol, Italy
- Faculty of Agricultural, Environmental and Food Sciences, Free University of Bolzano, Piazza Università 1, 39100, Bolzano, South Tyrol, Italy
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2
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Li J, Olevano V. Bethe-Salpeter equation insights into the photo-absorption function and exciton structure of chlorophyll a and b in light-harvesting complex II. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2022; 232:112475. [PMID: 35644069 DOI: 10.1016/j.jphotobiol.2022.112475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 10/18/2022]
Abstract
The photo-absorption process and the excitation of chlorophyll (Chl) is the primary and essential step of photosynthesis in green plants. By solving the Bethe-Salpeter equation (BSE) on top of the GW approximation within ab initio many-body perturbation theory, we calculate the photo-absorption function and the excitons structure of Chl a and b in their in vivo conformations as measured by X-ray diffraction in the light-harvesting complex (LHC) II. BSE optical absorption spectra are in good agreement with the experiment and we discuss residual discrepancies. The experimental evidence of multiple Chla forms in vivo is explained by BSE. The Chla and Chlb BSE exciton wavefunctions present important charge-transfer differences on the Soret band. Q excitons are almost identical, apart from charge (both electron and hole) localization on the Chlb C7 aldheide formyl group, absent on the Chla methyl C7, that is exactly the group where the two chlorophylls differ.
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Affiliation(s)
- Jing Li
- Univ. Grenoble Alpes, Grenoble 38000, France; CEA, Leti, Minatec Campus, Grenoble 38054, France; CNRS, Institut Néel, Grenoble 38042, France; ETSF, Nano-Bio-Pharma Spectroscopy group, Grenoble 38000, France.
| | - Valerio Olevano
- Univ. Grenoble Alpes, Grenoble 38000, France; CNRS, Institut Néel, Grenoble 38042, France; ETSF, Nano-Bio-Pharma Spectroscopy group, Grenoble 38000, France.
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3
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Integration of Satellite-Based Optical and Synthetic Aperture Radar Imagery to Estimate Winter Cover Crop Performance in Cereal Grasses. REMOTE SENSING 2022. [DOI: 10.3390/rs14092077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The magnitude of ecosystem services provided by winter cover crops is linked to their performance (i.e., biomass and associated nitrogen content, forage quality, and fractional ground cover), although few studies quantify these characteristics across the landscape. Remote sensing can produce landscape-level assessments of cover crop performance. However, commonly employed optical vegetation indices (VI) saturate, limiting their ability to measure high-biomass cover crops. Contemporary VIs that employ red-edge bands have been shown to be more robust to saturation issues. Additionally, synthetic aperture radar (SAR) data have been effective at estimating crop biophysical characteristics, although this has not been demonstrated on winter cover crops. We assessed the integration of optical (Sentinel-2) and SAR (Sentinel-1) imagery to estimate winter cover crops biomass across 27 fields over three winter–spring seasons (2018–2021) in Maryland. We used log-linear models to predict cover crop biomass as a function of 27 VIs and eight SAR metrics. Our results suggest that the integration of the normalized difference red-edge vegetation index (NDVI_RE1; employing Sentinel-2 bands 5 and 8A), combined with SAR interferometric (InSAR) coherence, best estimated the biomass of cereal grass cover crops. However, these results were season- and species-specific (R2 = 0.74, 0.81, and 0.34; RMSE = 1227, 793, and 776 kg ha−1, for wheat (Triticum aestivum L.), triticale (Triticale hexaploide L.), and cereal rye (Secale cereale), respectively, in spring (March–May)). Compared to the optical-only model, InSAR coherence improved biomass estimations by 4% in wheat, 5% in triticale, and by 11% in cereal rye. Both optical-only and optical-SAR biomass prediction models exhibited saturation occurring at ~1900 kg ha−1; thus, more work is needed to enable accurate biomass estimations past the point of saturation. To address this continued concern, future work could consider the use of weather and climate variables, machine learning models, the integration of proximal sensing and satellite observations, and/or the integration of process-based crop-soil simulation models and remote sensing observations.
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4
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Rammler T, Wackenhut F, Zur Oven-Krockhaus S, Rapp J, Forchhammer K, Harter K, Meixner AJ. Strong coupling between an optical microcavity and photosystems in single living cyanobacteria. JOURNAL OF BIOPHOTONICS 2022; 15:e202100136. [PMID: 34761529 DOI: 10.1002/jbio.202100136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 10/15/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
The first step in photosynthesis is an extremely efficient energy transfer mechanism that led to the debate to which extent quantum coherence may be involved in the energy transfer between the photosynthetic pigments. In search of such a coherent behavior, we have embedded living cyanobacteria between the parallel mirrors of an optical microresonator irradiated with low intensity white light. As a consequence, we observe vacuum Rabi splitting in the transmission and fluorescence spectra as a result of strong light matter coupling of the chlorophyll a molecules in the photosystems (PSs) and the cavity modes. The Rabi-splitting scales with the number of the PSs chlorophyll a pigments involved in strong coupling indicating a delocalized polaritonic state. Our data provide evidence that a delocalized polaritonic state can be established between the chlorophyll a molecule of the PSs in living cyanobacterial cells at ambient conditions in a microcavity.
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Affiliation(s)
- Tim Rammler
- Institute of Physical and Theoretical Chemistry, University of Tübingen, Tübingen, Germany
- Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
| | - Frank Wackenhut
- Institute of Physical and Theoretical Chemistry, University of Tübingen, Tübingen, Germany
| | - Sven Zur Oven-Krockhaus
- Institute of Physical and Theoretical Chemistry, University of Tübingen, Tübingen, Germany
- Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
| | - Johanna Rapp
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Karl Forchhammer
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Klaus Harter
- Center for Plant Molecular Biology, University of Tübingen, Tübingen, Germany
| | - Alfred J Meixner
- Institute of Physical and Theoretical Chemistry, University of Tübingen, Tübingen, Germany
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5
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Qi Q, Taniguchi M, Lindsey JS. Heuristics from Modeling of Spectral Overlap in Förster Resonance Energy Transfer (FRET). J Chem Inf Model 2019; 59:652-667. [PMID: 30715870 DOI: 10.1021/acs.jcim.8b00753] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Among the photophysical parameters that underpin Förster resonance energy transfer (FRET), perhaps the least explored is the spectral overlap term ( J). While by definition J increases linearly with acceptor molar absorption coefficient (ε(A) in M-1 cm-1), is proportional to wavelength (λ4), and depends on the degree of overlap of the donor fluorescence and acceptor absorption spectra, the question arose as to the value of J for the case of perfect spectral overlap versus that for representative fluorophores with incomplete spectral overlap. Here, Gaussian distributions of absorption and fluorescent spectra have been modeled that encompass varying degrees of overlap, full-width-at-half-maximum (fwhm), and Stokes shift. For ε(A) = 105 M-1 cm-1 and perfect overlap, the J value (in M-1 cm-1 nm4) ranges from 1.15 × 1014 (200 nm) to 7.07 × 1016 (1000 nm), is almost linear with λ4 (average of λabs and λflu), and is nearly independent of fwhm. For visible-region fluorophores with perfectly overlapped Gaussian spectra, the resulting value of J ( JG-0) is ∼0.71 ε(A)λ4 (M-1 cm-1 nm4). The experimental J values for homotransfer, as occurs in light-harvesting antennas, were calculated with spectra from a static database of 60 representative compounds (12 groups, 5 compounds each) and found to range from 4.2 × 1010 ( o-xylene) to 5.3 × 1016 M-1 cm-1 nm4 (a naphthalocyanine). The degree of overlap, defined by the ratio of the experimental J to the model JG-0 for perfectly overlapped spectra, ranges from ∼0.5% (coumarin 151) to 77% (bacteriochlorophyll a). The results provide insights into how a variety of factors affect the resulting J values. The high degree of spectral overlap for (bacterio)chlorophylls prompts brief conjecture concerning the relevance of energy transfer to the question "why chlorophyll".
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Affiliation(s)
- Qi Qi
- Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States
| | - Masahiko Taniguchi
- Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States
| | - Jonathan S Lindsey
- Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States
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6
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Kume A, Akitsu T, Nasahara KN. Why is chlorophyll b only used in light-harvesting systems? JOURNAL OF PLANT RESEARCH 2018; 131:961-972. [PMID: 29992395 PMCID: PMC6459968 DOI: 10.1007/s10265-018-1052-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 06/13/2018] [Indexed: 05/09/2023]
Abstract
Chlorophylls (Chl) are important pigments in plants that are used to absorb photons and release electrons. There are several types of Chls but terrestrial plants only possess two of these: Chls a and b. The two pigments form light-harvesting Chl a/b-binding protein complexes (LHC), which absorb most of the light. The peak wavelengths of the absorption spectra of Chls a and b differ by c. 20 nm, and the ratio between them (the a/b ratio) is an important determinant of the light absorption efficiency of photosynthesis (i.e., the antenna size). Here, we investigated why Chl b is used in LHCs rather than other light-absorbing pigments that can be used for photosynthesis by considering the solar radiation spectrum under field conditions. We found that direct and diffuse solar radiation (PARdir and PARdiff, respectively) have different spectral distributions, showing maximum spectral photon flux densities (SPFD) at c. 680 and 460 nm, respectively, during the daytime. The spectral absorbance spectra of Chls a and b functioned complementary to each other, and the absorbance peaks of Chl b were nested within those of Chl a. The absorption peak in the short wavelength region of Chl b in the proteinaceous environment occurred at c. 460 nm, making it suitable for absorbing the PARdiff, but not suitable for avoiding the high spectral irradiance (SIR) waveband of PARdir. In contrast, Chl a effectively avoided the high SPFD and/or high SIR waveband. The absorption spectra of photosynthetic complexes were negatively correlated with SPFD spectra, but LHCs with low a/b ratios were more positively correlated with SIR spectra. These findings indicate that the spectra of the photosynthetic pigments and constructed photosystems and antenna proteins significantly align with the terrestrial solar spectra to allow the safe and efficient use of solar radiation.
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Affiliation(s)
- Atsushi Kume
- Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan.
| | - Tomoko Akitsu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, 305-8572, Japan
| | - Kenlo Nishida Nasahara
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, 305-8572, Japan
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7
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Briggs WR. Remembering Jeanette Snyder Brown (1925-2014). PHOTOSYNTHESIS RESEARCH 2016; 127:287-293. [PMID: 26314735 DOI: 10.1007/s11120-015-0181-2] [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: 07/04/2015] [Accepted: 08/15/2015] [Indexed: 06/04/2023]
Abstract
Jeanette Snyder Brown (universally called Jan) was associated with the Department of Plant Biology, Carnegie Institution for Science (until recently Carnegie Institution of Washington) over a period of 37 years. Jan has left a scientific legacy of extensive publications concerned with photosynthetic pigments and their organization, and a historic collection of portraits of scientists who were prominent during her long tenure in the Department of Plant Biology. This legacy will stand for many years to come.
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Affiliation(s)
- Winslow R Briggs
- Department of Plant Biology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA.
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8
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Oudshoorn HP, Thomas JB. CURVE ANALYSIS OF THE RED ABSORPTION BAND OF CHLOROPHYLLbIN ULVA LACTUCA. ACTA ACUST UNITED AC 2015. [DOI: 10.1111/j.1438-8677.1975.tb00992.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
| | - J. B. Thomas
- Vakgroep Biofysica, Laboratorium voor Experimentele Fysica; Utrecht
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9
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Affiliation(s)
- G. Van Ginkel
- Vakgroep Biofysica, Laboratorium voor Experimentele Fysica; Utrecht
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10
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Hammans JWK, Thomas JB. ON THE CORRELATION BETWEEN THE AMOUNTS OF CHLOROPHYLLBAND CHLOROPHYLLAFORMS IN VARIOUS PLANTS. ACTA ACUST UNITED AC 2015. [DOI: 10.1111/j.1438-8677.1976.tb01054.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - J. B. Thomas
- Vakgroep Biofysica, Laboratorium voor Experimentele Fysica; Utrecht
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11
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Jennings RC, Zucchelli G. Antenna entropy in plant photosystems does not reduce the free energy for primary charge separation. Biophys Chem 2014; 195:16-21. [PMID: 25190479 DOI: 10.1016/j.bpc.2014.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 08/12/2014] [Accepted: 08/12/2014] [Indexed: 11/17/2022]
Abstract
We have investigated the concept of the so-called "antenna entropy" of higher plant photosystems. Several interesting points emerge: 1. In the case of a photosystemwhich harbours an excited state, the “antenna entropy” is equivalent to the configurational (mixing) entropy of a thermodynamic canonical ensemble. The energy associated with this parameter has been calculated for a hypothetical isoenergetic photosystem, photosystem I and photosystem II, and comes out in the range of 3.5 - 8% of the photon energy considering 680 nm. 2. The “antenna entropy” seems to be a rather unique thermodynamic phenomenon, in as much as it does not modify the free energy available for primary photochemistry, as has been previously suggested. 3. It is underlined that this configurational (mixing) entropy, unlike heat dispersal in a thermal system, does not involve energy dilution. This points out an important difference between thermal and electronic energy dispersal.
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Affiliation(s)
- Robert C Jennings
- Consiglio Nazionale delle Ricerche, Istituto di Biofisica, sede di Milano, via Giovanni Celoria 26, 20133 Milan, Italy; Dipartimento di Bioscienze, Università degli Studi di Milano, via Giovanni Celoria 26, 20133 Milan, Italy.
| | - Giuseppe Zucchelli
- Consiglio Nazionale delle Ricerche, Istituto di Biofisica, sede di Milano, via Giovanni Celoria 26, 20133 Milan, Italy; Dipartimento di Bioscienze, Università degli Studi di Milano, via Giovanni Celoria 26, 20133 Milan, Italy
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12
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Omar AF, Atan H, MatJafri MZ. Visible Spectral Linearisation, Gradient Shift and Normalisation in Quantifying Carambola Acidity. FOOD BIOPHYS 2012. [DOI: 10.1007/s11483-012-9267-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Vollsnes AV, Melø TB, Futsaether CM. Photomorphogenesis and pigment induction in lentil seedling roots exposed to low light conditions. PLANT BIOLOGY (STUTTGART, GERMANY) 2012; 14:467-474. [PMID: 22117590 DOI: 10.1111/j.1438-8677.2011.00516.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Although roots are normally hidden in soil, they may inadvertently be exposed to low light levels in experiments or in natural conditions through cracks or light transmittance through the soil. Light has been implicated in root morphogenesis. Thus, effects of low light conditions on lentil (Lens culinaris L. cv. Verte du Puy) root morphology and root pigmentation were studied. Lentil seedlings were grown in peat or transparent, nutrient-fortified agar at a 12-h light (PAR 240 μmol · m(-2) · s(-1)), 12-h dark cycle. Roots were exposed to low levels (≈ 1-10 μmol · m(-2) · s(-1)) of broadband white light, either directly or indirectly by aboveground light penetrating the growth medium. Control roots were grown in darkness. In situ spectroscopy was used to measure transmittance and reflectance spectra of intact root tissue by mounting the upper part of the primary root directly in a spectrophotometer equipped with an integrating sphere attachment. The transmittance and reflectance spectra were used to calculate the in situ root absorbance spectrum. Absorbance bands were found in the regions 480-500 nm and 650-680 nm, possibly due to low levels of root-localised carotenoids and chlorophylls, respectively. Low light levels (≈ 1-10 μmol · m(-2) · s(-1) ) transmitted through the growth medium significantly increased root pigment concentration and root biomass, and altered root morphology by enhancing lateral root formation and inhibiting root elongation relative to roots grown in complete darkness. The light-induced changes in root morphogenesis and pigmentation appear to be primarily due to upper root light perception.
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Affiliation(s)
- A V Vollsnes
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, Ås, Norway
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14
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Zucchelli G, Santabarbara S, Jennings RC. The Qy Absorption Spectrum of the Light-Harvesting Complex II As Determined by Structure-Based Analysis of Chlorophyll Macrocycle Deformations. Biochemistry 2012; 51:2717-36. [DOI: 10.1021/bi201677q] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Giuseppe Zucchelli
- CNR-Istituto di Biofisica, Sezione di Milano
and Dipartimento di Biologia, Università degli Studi di Milano, via Giovanni Celoria 26, 20133
Milano Italy
| | - Stefano Santabarbara
- CNR-Istituto di Biofisica, Sezione di Milano
and Dipartimento di Biologia, Università degli Studi di Milano, via Giovanni Celoria 26, 20133
Milano Italy
| | - Robert C. Jennings
- CNR-Istituto di Biofisica, Sezione di Milano
and Dipartimento di Biologia, Università degli Studi di Milano, via Giovanni Celoria 26, 20133
Milano Italy
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15
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Seasonal changes in the excess energy dissipation from Photosystem II antennae in overwintering evergreen broad-leaved trees Quercus myrsinaefolia and Machilus thunbergii. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 104:348-56. [DOI: 10.1016/j.jphotobiol.2010.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 12/01/2010] [Accepted: 12/01/2010] [Indexed: 11/23/2022]
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16
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Wasielewski MR, Studier MH, Katz JJ. Covalently linked chlorophyll a dimer: A biomimetic model of special pair chlorophyll. Proc Natl Acad Sci U S A 2010; 73:4282-6. [PMID: 16592367 PMCID: PMC431433 DOI: 10.1073/pnas.73.12.4282] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The synthesis of a covalent dimer of chlorophyll a which possesses properties strikingly similar to those exhibited by P700 special pair chlorophyll in vivo is described. The covalent dimer is characterized by several spectroscopic techniques. Hydrogen bonding nucleophiles, such as water, primary alcohols, and primary thiols, are effective in generating a species from solutions of 10 muM covalent dimer in hydrophobic solvents which absorbs light near 700 nm. Formation of this in vitro special pair is a rapid, spontaneous process at room temperature. The range of nucleophiles which promote this process suggests that amino acid residues may function in a similar fashion to form P700 in chlorophyll-protein complexes. The photochemical properties of this in vitro special pair mimic those of in vivo P700 species. The 697 nm absorption of the in vitro special pair undergoes photo-bleaching rapidly in the presence of iodine that results in the production of a cation radical which exhibits an electron spin resonance signal similar to that of oxidized P700 observed in Chlorella vulgaris.
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Affiliation(s)
- M R Wasielewski
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439
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17
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Gasanov RA, French CS. Chlorophyll composition and photochemical activity of photosystems detached from chloroplast grana and stroma lamellae. Proc Natl Acad Sci U S A 2010; 70:2082-5. [PMID: 16592101 PMCID: PMC433670 DOI: 10.1073/pnas.70.7.2082] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A stroma fraction that has photosystem 1 activity and grana lamellae fractions that have activities for both photosystems were isolated by differential centrifugation of a needle valve homogenate. Subsequent fractions, corresponding to photosystems 1 (F-1D) and 2 (F-2D) were isolated by digitonin treatment of the grana lamellae (P-10K) and compared with respect to their chlorophyll composition and electron transport activities.Fraction F-2D from grana lamellae having photosystem 2 activity is primarily active in photosystem 2 and contains only the four major forms of chlorophyll a with a predominance of chlorophyll a 677 nm. This fraction differs from the original grana membranes in the absence of the longwavelength form of chlorophyll a and in the widening of the absorption band of chlorophyll a 682 nm from 10.9 to 15.6 nm.Photosystem 1 particles from grana and stroma both have high photosystem 1 activity but differ from each other in the proportions of the four major forms of chlorophyll a. The short-wavelength forms of chlorophyll a and also chlorophyll b 650 nm in particles from grana lamellae comprise relatively more total area than these same forms in the particles from stroma. In addition, the fraction corresponding to photosystem 1 from grana lamellae is not shifted to the long-wavelength side of the main absorption maximum, as compared to the photosystem 2 particles from grana and the original grana membrane fraction; this is usually observed in fractions that have photosystem 1 activity. Furthermore, the longest wavelength form of chlorophyll a in the photosystem 1 particles from grana is at 700 nm, while in the same fraction from stroma, it is at 706 nm.The half-width of the four main forms of chlorophyll a and both forms of chlorophyll b in the photosystem 1 fraction from grana is narrower than that of the corresponding forms in the same fraction from stroma. This may indicate a different packing of pigment molecules that are aggregated on the surface of membranes of these two fractions.
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Affiliation(s)
- R A Gasanov
- Carnegie Institution, Stanford, California 94305
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18
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Duxbury Z, Schliep M, Ritchie RJ, Larkum AWD, Chen M. Chromatic photoacclimation extends utilisable photosynthetically active radiation in the chlorophyll d-containing cyanobacterium, Acaryochloris marina. PHOTOSYNTHESIS RESEARCH 2009; 101:69-75. [PMID: 19582591 DOI: 10.1007/s11120-009-9466-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Accepted: 06/23/2009] [Indexed: 05/28/2023]
Abstract
Chromatic photoacclimation and photosynthesis were examined in two strains of Acaryochloris marina (MBIC11017 and CCMEE5410) and in Synechococcus PCC7942. Acaryochloris contains Chl d, which has an absorption peak at ca 710 nm in vivo. Cultures were grown in one of the three wavelengths (525 nm, 625 nm and 720 nm) of light from narrow-band photodiodes to determine the effects on pigment composition, growth rate and photosynthesis: no growth occurred in 525 nm light. Synechococcus did not grow in 720 nm light because Chl a does not absorb effectively at this long wavelength. Acaryochloris did grow in 720 nm light, although strain MBIC11017 showed a decrease in phycobilins over time. Both Synechococcus and Acaryochloris MBIC11017 showed a dramatic increase in phycobilin content when grown in 625 nm light. Acaryochloris CCMEE5410, which lacks phycobilins, would not grow satisfactorily under 625 nm light. The cells adjusted their pigment composition in response to the light spectral conditions under which they were grown. Photoacclimation and the Q (y) peak of Chl d could be understood in terms of the ecological niche of Acaryochloris, i.e. habitats enriched in near infrared radiation.
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Affiliation(s)
- Zane Duxbury
- School of Biological Sciences (A08), University of Sydney, Sydney, NSW, 2006, Australia
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19
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Pfündel EE. Deriving room temperature excitation spectra for photosystem I and photosystem II fluorescence in intact leaves from the dependence of FV/FM on excitation wavelength. PHOTOSYNTHESIS RESEARCH 2009; 100:163-177. [PMID: 19544007 DOI: 10.1007/s11120-009-9453-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Accepted: 06/01/2009] [Indexed: 05/27/2023]
Abstract
The F(0) and F(M) level fluorescence from a wild-type barley, a Chl b-less mutant barley, and a maize leaf was determined from 430 to 685 nm at 10 nm intervals using pulse amplitude-modulated (PAM) fluorimetry. Variable wavelengths of the pulsed excitation light were achieved by passing the broadband emission of a Xe flash lamp through a birefringent tunable optical filter. For the three leaf types, spectra of F(V)/F(M) (=(F(M) - F(0))/F (M)) have been derived: within each of the three spectra of F(V)/F(M), statistically meaningful variations were detected. Also, at distinct wavelength regions, the (V)/F(M) differed significantly between leaf types. From spectra of F(V)/F (M), excitation spectra of PS I and PS II fluorescence were calculated using a model that considers PS I fluorescence to be constant but variable PS II fluorescence. The photosystem spectra suggest that LHC II absorption results in high values of F(V)/F(M) between 470 and 490 nm in the two wild-type leaves but the absence of LHC II in the Chl b-less mutant barley leaf decreases the F(V)/F(M) at these wavelengths. All three leaves exhibited low values of F(V)/F(M) around 520 nm which was tentatively ascribed to light absorption by PS I-associated carotenoids. In the 550-650 nm region, the F(V)/F(M) in the maize leaf was lower than in the barley wild-type leaf which is explained with higher light absorption by PS I in maize, which is a NADP-ME C(4) species, than in barley, a C(3) species. Finally, low values of F(V)/F(M) at 685 in maize leaf and in the Chl b-less mutant barley leaf are in agreement with preferential PS I absorption at this wavelength. The potential use of spectra of the F(V)/F(M) ratio to derive information on spectral absorption properties of PS I and PS II is discussed.
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20
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Zucchelli G, Brogioli D, Casazza AP, Garlaschi FM, Jennings RC. Chlorophyll ring deformation modulates Qy electronic energy in chlorophyll-protein complexes and generates spectral forms. Biophys J 2007; 93:2240-54. [PMID: 17513370 PMCID: PMC1959541 DOI: 10.1529/biophysj.107.104554] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The possibility that the chlorophyll (chl) ring distortions observed in the crystal structures of chl-protein complexes are involved in the transition energy modulation, giving rise to the spectral forms, is investigated. The out-of-plane chl-macrocycle distortions are described using an orthonormal set of deformations, defined by the displacements along the six lowest-frequency, out-of-plane normal coordinates. The total chl-ring deformation is the linear combination of these six deformations. The two higher occupied and the two lower unoccupied chl molecular orbitals, which define the Q(y) electronic transition, have the same symmetry as four of the six out-of-plane lowest frequency modes. We assume that a deformation along the normal-coordinate having the same symmetry as a given molecular orbital will perturb that orbital and modify its energy. The changes in the chl Q(y) transition energies are evaluated in the Peridinin-Chl-Protein complex and in light harvesting complex II (LHCII), using crystallographic data. The macrocycle deformations induce a distribution of the chl Q(y) electronic energy transitions which, for LHCII, is broader for chla than for chlb. This provides the physical mechanism to explain the long-held view that the chla spectral forms in LHCII are both more numerous and cover a wider energy range than those of chlb.
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Affiliation(s)
- Giuseppe Zucchelli
- Consiglio Nazionale Delle Ricerche-Istituto di Biofisica, Dipartimento di Biologia, Università degli Studi di Milano, Milan, Italy.
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21
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Nishigaki A, Ohshima S, Nakayama K, Okada M, Nagashima U. Application of Molecular Orbital Calculations to Interpret the Chlorophyll Spectral Forms in Pea Photosystem II¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2001)0730245aomoct2.0.co2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Evangelista V, Frassanito AM, Passarelli V, Barsanti L, Gualtieri P. Microspectroscopy of the Photosynthetic Compartment of Algae. Photochem Photobiol 2006; 82:1039-46. [PMID: 17205627 DOI: 10.1562/2006-01-11-ra-772] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We performed microspectroscopic evaluation of the pigment composition of the photosynthetic compartments of algae belonging to different taxonomic divisions and higher plants. The feasibility of microspectroscopy for discriminating among species and/or phylogenetic groups was tested on laboratory cultures. Gaussian bands decompositions and a fitting algorithm, together with fourth-derivative transformation of absorbance spectra, provided a reliable discrimination among chlorophylls a, b and c, phycobiliproteins and carotenoids. Comparative analysis of absorption spectra highlighted the evolutionary grouping of the algae into three main lineages in accordance with the most recent endosymbiotic theories.
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23
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Kopetz KJ, Kolossov VL, Rebeiz CA. Chloroplast biogenesis 89: development of analytical tools for probing the biosynthetic topography of photosynthetic membranes by determination of resonance excitation energy transfer distances separating metabolic tetrapyrrole donors from chlorophyll a acceptors. Anal Biochem 2005; 329:207-19. [PMID: 15158479 DOI: 10.1016/j.ab.2004.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2003] [Indexed: 10/26/2022]
Abstract
The thorough understanding of photosynthetic membrane assembly requires a deeper knowledge of the coordination and regulation of the chlorophyll (Chl) and thylakoid apoprotein biosynthetic pathways. As a working hypothesis we have recently proposed three different Chl-thylakoid apoprotein biosynthesis models: a single-branched Chl biosynthetic pathway (SBP)-single location model, a SBP-multilocation model, and a multibranched Chl biosynthetic pathway (MBP)-sublocation model. The detection of resonance excitation energy transfer between tetrapyrrole precursors of Chl, and several Chl-protein complexes, has made it possible to test the validity of the proposed Chl-thylakoid apoprotein biosynthesis models by resonance excitation energy transfer determinations. In this work, resonance excitation energy transfer techniques that allow the determination of distances separating tetrapyrrole donors from Chl-protein acceptors in green plants by using readily available electronic spectroscopic instrumentation are developed. It is concluded that the calculated distances are compatible with the MBP-sublocation model and incompatible with the operation of the SBP-single location Chl-protein biosynthesis model.
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Affiliation(s)
- Karen J Kopetz
- Laboratory of Plant Biochemistry and Photobiology, NRES, 240 A, ERML, 1201 West Gregory Avenue, University of Illinois, Urbana, IL 61801, USA
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24
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Zucchelli G, Jennings RC, Garlaschi FM, Cinque G, Bassi R, Cremonesi O. The calculated in vitro and in vivo chlorophyll a absorption bandshape. Biophys J 2002; 82:378-90. [PMID: 11751324 PMCID: PMC1302477 DOI: 10.1016/s0006-3495(02)75402-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The room temperature absorption bandshape for the Q transition region of chlorophyll a is calculated using the vibrational frequency modes and Franck-Condon (FC) factors obtained by line-narrowing spectroscopies of chlorophyll a in a glassy (Rebane and Avarmaa, Chem. Phys. 1982; 68:191-200) and in a native environment (Gillie et al., J. Phys. Chem. 1989; 93:1620-1627) at low temperatures. The calculated bandshapes are compared with the absorption spectra of chlorophyll a measured in two different solvents and with that obtained in vivo by a mutational analysis of a chlorophyll-protein complex. It is demonstrated that the measured distributions of FC factors can account for the absorption bandshape of chlorophyll a in a hexacoordinated state, whereas, when pentacoordinated, reduced FC coupling for vibrational frequencies in the range 540-850 cm(-1) occurs. The FC factor distribution for pentacoordinated chlorophyll also describes the native chlorophyll a spectrum but, in this case, either a low-frequency mode (nu < 200 cm(-1)) must be added or else the 262-cm(-1) mode must increase in coupling by about one order of magnitude to describe the skewness of the main absorption bandshape.
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Affiliation(s)
- Giuseppe Zucchelli
- Centro Consiglio Nazionale delle Ricerche, Biologia Cellulare e Molecolare Piante, Dipartimento di Biologia, Università degli Studi di Milano, 20133 Milano, Italy.
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25
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Biggins J, Svejkovský J. Reorientation of a long-wavelength chlorophyll-a
-protein by divalent cations as revealed by the linear dichroism of magneto-oriented thylakoids. FEBS Lett 2001. [DOI: 10.1016/0014-5793(78)80217-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Nishigaki A, Ohshima S, Nakayama K, Okada M, Nagashima U. Application of molecular orbital calculations to interpret the chlorophyll spectral forms in pea photosystem II. Photochem Photobiol 2001; 73:245-8. [PMID: 11281020 DOI: 10.1562/0031-8655(2001)073<0245:aomoct>2.0.co;2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The energy and oscillator strength of electronic transitions of chlorophyll (Chl)-amino acid complexes were calculated by using molecular orbital methods. The energies varied widely with coordinated amino acids and the difference between the maximum and minimum energy was about 830 cm-1. This energy difference was comparable with the spreading of absorption bands for light-harvesting Chl-protein complexes of photosystem II (LHC II) of green plants. The feature of the Qy band for pea LHC II was interpreted with the aid of the calculated energies and oscillator strengths. Four spectral components of the band were assigned to individual Chl-amino acid complexes.
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Affiliation(s)
- A Nishigaki
- Department of Biomolecular Science, Toho University, Miyama, Chiba, Japan
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27
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Koehne B, Elli G, Jennings RC, Wilhelm C, Trissl H. Spectroscopic and molecular characterization of a long wavelength absorbing antenna of Ostreobium sp. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1412:94-107. [PMID: 10393253 DOI: 10.1016/s0005-2728(99)00061-4] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
One of the strains of the marine green alga Ostreobium sp. possesses an exceptionally large number of long wavelength absorbing chlorophylls (P. Haldall, Biol. Bull. 134, 1968, 411-424) as evident from a distinct shoulder in the absorption spectrum at around 710 nm while in the other strain this shoulder is absent. Therefore, Ostreobium offers a unique possibility to explore the origin of these red-shifted chlorophylls, because strains with and without these spectral forms can be compared. Here, we characterize these red forms spectroscopically by absorption, fluorescence and CD spectroscopy. In the CD spectra at least three spectroscopic red forms are identified which lead to an unusual room temperature fluorescence spectrum that peaks at 715 nm. The gel electrophoretic pattern from thylakoids of Ostreobium sp. shows an intense band at 22 kDa which correlates with the presence or absence of long wavelength absorbing pigments. By protein sequencing of the N-terminus of the 22-kDa polypeptide and sequence alignments, this was identified as an Lhca1-type light-harvesting complex. The abundance of this polypeptide - and a possibly co-migrating one - in Ostreobium sp. indicates an antenna size of approximately 340 chlorophyll molecules (Chl a and Chl b) per PS IIalpha reaction center, which is significantly larger than in higher plants ( approximately 240). The red forms are more abundant in the interior of the thalli where a 'shade-light' light field is expected than in the white-light exposed surface. This demonstrates that algae exist which may be able to up-regulate the synthesis of large amounts of LHCI and associated red forms under appropriate illumination conditions.
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Affiliation(s)
- B Koehne
- Abteilung Biophysik, Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastrasse 11, D-49069, Osnabrück, Germany
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Dudkowiak A, Nakamura C, Arai T, Miyake J. Interactions of chlorophyll a with synthesized peptide in aqueous solution. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1998; 45:43-50. [PMID: 9819898 DOI: 10.1016/s1011-1344(98)00158-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The interactions between chlorophyll a and synthesized peptides have been studied using optical spectroscopy. Three 30-residue peptides are designed and synthesized: an amphiphilic peptide without histidine (L), an amphiphilic peptide with histidine (L/H) and a hydrophilic peptide (K/E). These peptide properties thereby allow us to examine the effect of the peptide hydrophobicity and/or histidine residue on pigment-peptide interactions. On mixing with peptides, chlorophyll a has a main absorption band in the Qy region with the maximum at 672 nm. For all three peptides, fluorescence patterns show that at a low concentration of the peptide (0.05 mM) in aqueous solution, the energy is transferred among various forms of the pigment. Only peptide L/H at high concentration (0.5 mM) in solution retains the Qy band of chlorophyll a at 672 nm, and the emission is that typically seen for the monomeric form of the pigment. The aggregation of chlorophyll a is suppressed most strongly in the presence of the peptides L/H. The results suggest that chlorophyll a is ligated to a histidine residue, located in the hydrophobic region of the peptides L/H, and in surrounded or shielded by the peptide alpha-helixes.
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Affiliation(s)
- A Dudkowiak
- National Institute for Advanced Interdisciplinary Research, AIST/MITI, Ibaraki, Japan
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29
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Kurawaki J, Sameshima Y, Kusumoto Y. Conformation-Dependent Energy Transfer between Copolypeptide Carrying l-Ornithine and l-Tyrosine and Chlorophyll in Aqueous Sodium Dodecyl Sulfate Solution. J Phys Chem B 1997. [DOI: 10.1021/jp971222v] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Junichi Kurawaki
- Chemical Institute, College of Liberal Arts, Kagoshima University, Korimoto, Kagoshima 890, Japan
| | - Yuriko Sameshima
- Chemical Institute, College of Liberal Arts, Kagoshima University, Korimoto, Kagoshima 890, Japan
| | - Yoshihumi Kusumoto
- Chemical Institute, College of Liberal Arts, Kagoshima University, Korimoto, Kagoshima 890, Japan
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30
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Schiller H, Senger H, Miyashita H, Miyachi S, Dau H. Light-harvesting in Acaryochloris marina--spectroscopic characterization of a chlorophyll d-dominated photosynthetic antenna system. FEBS Lett 1997; 410:433-6. [PMID: 9237677 DOI: 10.1016/s0014-5793(97)00620-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Oxygenic photosynthesis of the prokaryote Acaryochloris marina involves chlorophyll d (Chl d) as the major pigment [Miyashita et al. (1996) Nature 383, 402]. Four spectral forms of Chl d (peak wavelengths: 694, 714, 726 and 740 nm) are resolvable by low-temperature absorption spectroscopy on intact cells. Based on fluorescence spectra (at 290 K and 77 K) and on analysis of fluorescence induction curves we conclude: (1) excitation energy is efficiently transferred between the various spectral forms of Chl d and the PS II reaction center; (2) Chl d serves as a light-harvesting pigment for both, Photosystem II (PS II) and PS I; (3) excitation energy transfer between PS II units occurs.
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Affiliation(s)
- H Schiller
- FB Biologie/Botanik, Philipps-Universität Marburg, Germany
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31
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Chapter 4 A lifetime journey with photosynthesis. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0069-8032(97)40007-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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32
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Apoprotein composition and spectroscopic characterization of the water-soluble peridinin—chlorophyll
a
—proteins from three symbiotic dinoflagellates. Proc Biol Sci 1997. [DOI: 10.1098/rspb.1991.0155] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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33
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Sanders R, Zandvoort MAMJ, Draaijer A, Levine YK, Gerritsen HC. Confocal Fluorescence Lifetime Imaging of Chlorophyll Molecules in Polymer Matrices. Photochem Photobiol 1996. [DOI: 10.1111/j.1751-1097.1996.tb01840.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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34
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Miyashita H, Ikemoto H, Kurano N, Adachi K, Chihara M, Miyachi S. Chlorophyll d as a major pigment. Nature 1996. [DOI: 10.1038/383402a0] [Citation(s) in RCA: 375] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Jennings RC, Garlaschi FM, Finzi L, Zucchelli G. Slow exciton trapping in Photosystem II: A possible physiological role. PHOTOSYNTHESIS RESEARCH 1996; 47:167-173. [PMID: 24301824 DOI: 10.1007/bf00016179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/1995] [Accepted: 12/06/1995] [Indexed: 06/02/2023]
Abstract
Photosystem II, which has a primary photochemical charge separation time of about 300 ps, is the slowest trapping of all photosystems. On the basis of an analysis of data from the literature this is shown to be due to a number of partly independent factors: a shallow energy funnel in the antenna, an energetically shallow trap, exciton dynamics which are partly 'trap limited' and a large antenna. It is argued that the first three of these properties of Photosystem II can be understood in terms of protective mechanisms against photoinhibition. These protective mechanisms, based on the generation of non photochemical quenching states mostly in the peripheral antenna, are able to decrease pheophytin reduction under conditions in which the primary quinone, QA, is already reduced, due to the slow trapping properties. The shallow antenna funnel is important in allowing quenching state-protective mechanisms in the peripheral antenna.
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Affiliation(s)
- R C Jennings
- Centro CNR sulla Biologia Cellulare e Molecolare delle Piante, Dipartimento di Biologia, Università di Milano, via Celoria 26, 20133, Milano, Italy
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36
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Jennings RC, Bassi R, Zucchelli G. Antenna structure and energy transfer in higher plant photosystems. ELECTRON TRANSFER II 1996. [DOI: 10.1007/3-540-60110-4_5] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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37
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Lokstein H, Leupold D, Voigt B, Nowak F, Ehlert J, Hoffmann P, Garab G. Nonlinear polarization spectroscopy in the frequency domain of light-harvesting complex II: absorption band substructure and exciton dynamics. Biophys J 1995; 69:1536-43. [PMID: 8534824 PMCID: PMC1236384 DOI: 10.1016/s0006-3495(95)80025-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Spectral substructure and ultrafast excitation dynamics have been investigated in the chlorophyll (Chl) a and b Qy region of isolated plant light-harvesting complex II (LHC II). We demonstrate the feasibility of Nonlinear Polarization Spectroscopy in the frequency domain, a novel photosynthesis research laser spectroscopic technique, to determine not only ultrafast population relaxation (T1) and dephasing (T2) times, but also to reveal the complex spectral substructure in the Qy band as well as the mode(s) of absorption band broadening at room temperature (RT). The study gives further direct evidence for the existence of up to now hypothetical "Chl forms". Of particular interest is the differentiated participation of the Chl forms in energy transfer in trimeric and aggregated LHC II. Limits for T2 are given in the range of a few ten fs. Inhomogeneous broadening does not exceed the homogeneous widths of the subbands at RT. The implications of the results for the energy transfer mechanisms in the antenna are discussed.
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Affiliation(s)
- H Lokstein
- Institut für Biologie (Pflanzenphysiologie), Humboldt-Universität zu Berlin, Germany
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38
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Osborne BA, Clabby GT, Horsley D, Nolan PF. Is acclimation required for success in high light environments? A case study using Mycelis muralis (L.) Dumort (Asteraceae). THE NEW PHYTOLOGIST 1994; 127:363-375. [PMID: 33874512 DOI: 10.1111/j.1469-8137.1994.tb04287.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In the field significant differences in maximum photosynthetic O2 -exchange rate (Pm ) were found between leaves of Mycelis muralis (L.) Dumort (Asteraceae) collected from woodland and exposed habitats, with the highest values in the exposed sites- However, there were no differences in the Pm of leaves collected from plants growing in grikes (fissures in the limestone pavement), of exposed limestone pavement, despite a greater than four-fold difference in the integrated daily irradiance. Leaves of plants from the open pavement had lower photon yields (ø1 ) and higher dark respiration rates and light compensation points, in comparison to shaded plants. Under controlled environmental conditions the highest Pm of leaves from plants subjected to variations in irradiance were found at the intermediate (8-6 mol photon m-2 d-1 growth light level used. At the highest growth irradiance 17.3 mol photon m-2 d-1 used in the laboratory both Pm and øl were reduced, although the latest plant biomass was found at this irradiance. No changes were found in the chlorophyll a:b ratio over the same range of irradiances. Examination of plant populations of M. muralis, collected from open or shaded habitats and exposed to growth irradiances that covered the range over which increases in photosynthesis were, observed in the laboratory (0.86-8.6 mol photon m-2 d-1 ), resulted in changes in leaf structure and pigment composition. The chlorophyll a:b ratio was low and largely independent of irradiance or the origin of the plant population. Differences in total chlorophyll content were small with the lowest values m the Durrow woodland populations at both irradiances. No variations were found in a number of chloroplast thylakoid structural features. In particular, the ratio of oppressed to non-appressed membranes was unchanged by growth at the two irradiances, consistent with an invariant chlorophyll a:b ratio. Based on peaks in the difference spectra the woodland populations had mi enhanced in vivo absorption at λlD= 650 and 706 nm when grown at low irradiance. These peaks were absent from the population collected from the open limestone pavement. The significance of the enhanced absorption at low irradiance and the possibility that these peaks represent long-wavelength forms of chlorophyll a (λlD = 706) and b (λlD = 650) is discussed. A particular feature of plants grown at high irradiance was an enhanced anthocyanin content in comparison to those grown at low irradiance. This was associated with an increase in absorptance. particularly in the green region (λlD = 550 nm) of the visible spectrum. Overall these results suggest that complete acclimation of photosynthesis and an ability to modulate light-harvesting is not a prerequisite, for success in a high light environment.
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Affiliation(s)
- Bruce A Osborne
- Botany Department, University College Dublin, Belfield, Dublin 4, Ireland
| | - Gerry T Clabby
- Botany Department, University College Dublin, Belfield, Dublin 4, Ireland
| | - David Horsley
- Botany Department, University College Dublin, Belfield, Dublin 4, Ireland
| | - Peter F Nolan
- Botany Department, University College Dublin, Belfield, Dublin 4, Ireland
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Woolf VM, Wittmershaus BP, Vermaas WF, Tran TD. Resolution of low-energy chlorophylls in Photosystem I of Synechocystis sp. PCC 6803 at 77 and 295 K through fluorescence excitation anisotropy. PHOTOSYNTHESIS RESEARCH 1994; 40:21-34. [PMID: 24311211 DOI: 10.1007/bf00019042] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/1992] [Accepted: 11/08/1993] [Indexed: 06/02/2023]
Abstract
Fluorescence excitation spectra of highly anisotropic emission from Photosystem I (PS I) were measured at 295 and 77 K on a PS II-less mutant of the cyanobacterium Synechocystis sp. PCC 6803 (S. 6803). When PS I was excited with light at wavelengths greater than 715 nm, fluorescence observed at 745 nm was highly polarized with anisotropies of 0.32 and 0.20 at 77 and 295 K, respectively. Upon excitation at shorter wavelengths, the 745-nm fluorescence had low anisotropy. The highly anisotropic emission observed at both 77 and 295 K is interpreted as evidence for low-energy chlorophylls (Chls) in cyanobacteria at room temperature. This indicates that low-energy Chls, defined as Chls with first excited singlet-state energy levels below or near that of the reaction center, P700, are not artifacts of low-temperature measurements.If the low-energy Chls are a distinct subset of Chls and a simple two-pool model describes the excitation transfer network adequately, one can take advantage of the low-energy Chls' high anisotropy to approximate their fluorescence excitation spectra. Maxima at 703 and 708 nm were calculated from 295 and 77 K data, respectively. Upper limits for the number of low-energy Chls per P700 in PS I from S. 6803 were calculated to be 8 (295 K) and 11 (77 K).
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Affiliation(s)
- V M Woolf
- Department of Physics and Astronomy, Arizona State University, 85287, Tempe, AZ, USA
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40
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Zandvoort MAMJV, Wroabel D, Scholten AJ, Jager DD, Ginkel GV, Levine YK. SPECTROSCOPIC STUDY OF CHLOROPHYLL a IN ORGANIC SOLVENTS AND POLYMERIZED ANHYDROUS POLYVINYL MATRIX. Photochem Photobiol 1993. [DOI: 10.1111/j.1751-1097.1993.tb04939.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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41
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Shlbasaka M, Tanaka A, Tsiji H. CHANGES IN SPECTRAL PROPERTIES OF CHLOROPHYLL DURING GREENING OF BARLEY LEAVES. Photochem Photobiol 1993. [DOI: 10.1111/j.1751-1097.1993.tb09586.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Jennings RC, Bassi R, Garlaschi FM, Dainese P, Zucchelli G. Distribution of the chlorophyll spectral forms in the chlorophyll-protein complexes of photosystem II antenna. Biochemistry 1993; 32:3203-10. [PMID: 8461288 DOI: 10.1021/bi00064a002] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The chlorophyll-protein complexes that form the antenna system of photosystem II have been purified and analyzed in terms of the commonly observed chlorophyll spectral forms. With the exception of chlorophyll b, which is known to be associated with the complexes comprising the outer antenna (LHCII, CP24, CP26, CP29), the spectral forms occur with similar absorption maxima and are present in rather similar amounts in each of the antenna complexes. On the basis of the published chlorophyll stoichiometries for the complexes in photosystem II antenna, the distribution of the spectral forms in a "reconstituted" antenna has been determined. These data were used to calculate the equilibrium population of excited states within the various chlorophyll-protein complexes within photosystem II. This was compared with the light absorption capacity of each of the complexes in the "reconstituted" antenna. The ratio of these two parameters (excited-state equilibrium distribution/absorption capacity) was determined to be 1.21 for the inner (core) antenna and 0.88 for LHCII. The standard free energy change for exciton transfer from the outer to the inner antenna was calculated to be -0.17 kcal mol-1. It is concluded that the photosystem II antenna is arranged as a very shallow funnel.
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Affiliation(s)
- R C Jennings
- Dipartimento di Biologia, Università di Milano, Italy
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Trissl HW. Long-wavelength absorbing antenna pigments and heterogeneous absorption bands concentrate excitons and increase absorption cross section. PHOTOSYNTHESIS RESEARCH 1993; 35:247-263. [PMID: 24318755 DOI: 10.1007/bf00016556] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/1992] [Accepted: 10/05/1992] [Indexed: 06/02/2023]
Abstract
The light-harvesting apparatus of photosynthetic organisms is highly optimized with respect to efficient collection of excitation energy from photons of different wavelengths and with respect to a high quantum yield of the primary photochemistry. In many cases the primary donor is not an energetic trap as it absorbs hypsochromically compared to the most red-shifted antenna pigment present (long-wavelength antenna). The possible reasons for this as well as for the spectral heterogeneity which is generally found in antenna systems is examined on a theoretical basis using the approach of thermal equilibration of the excitation energy. The calculations show that long-wavelength antenna pigments and heterogeneous absorption bands lead to a concentration of excitons and an increased effective absorption cross section. The theoretically predicted trapping times agree remarkably well with experimental data from several organisms. It is shown that the kinetics of the energy transfer from a long-wavelength antenna pigment to a hypsochromically absorbing primary donor does not represent a major kinetic limitation. The development of long-wavelength antenna and spectrally heterogeneous absorption bands means an evolutionary advantage based on the chromatic adaptation of photosynthetic organelles to spectrally filtered light caused by self-absorption.
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Affiliation(s)
- H W Trissl
- Abt. Biophysik, Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastr. 11, D-4500, Osnabrück, Germany
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Trissl HW, Hecks B, Wulf K. INVARIABLE TRAPPING TIMES IN PHOTOSYSTEM I UPON EXCITATION OF MINOR LONG-WAVELENGTH-ABSORBING PIGMENTS. Photochem Photobiol 1993. [DOI: 10.1111/j.1751-1097.1993.tb02264.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Krasnovsky AA. Excited chlorophyll and related problems. PHOTOSYNTHESIS RESEARCH 1992; 33:177-193. [PMID: 24408662 DOI: 10.1007/bf00030029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/1992] [Accepted: 05/20/1992] [Indexed: 06/03/2023]
Abstract
A historical outline is presented of the primary light energy conversion in photosynthesis studied by our research group. We found that photoexcited chlorophylls, pheophytins and porphyrins are capable of reversible and irreversible oxido-reduction. The mechanism of the photosensitized electron transfer from donor to acceptor molecule is based on the reversible photochemical oxido-reduction of the pigment-sensitizer. This property of the excited pigments is realized in the reaction centres of photosynthetic cells when photooxidation of bacteriochlorophyll(s) or chlorophyll of Photosystem II is coupled to pheophytin reduction leading to the final charge separation.The studies of the state and function of pigments in the course of chlorophyll biosynthesis in cellular and non-cellular systems revealed different monomeric and aggregated forms of pigments and the phenomenon of self-assembly of various forms of chlorophylls, bacteriochlorophylls and protochlorophylls. The discovery of protochlorophyll photoreduction in non-cellular system allowed the study of the molecular mechanisms of this reaction.In order to construct models of photosynthetic charge separation, we used inorganic photocatalysts-semiconductors, mainly titanium dioxide, and pigments incorporated into detergent micelles or lipid vesicles. To prevent back reactions we used heterogeneous systems where primary unstable products were spatially separated; coupling of solubilized chlorophylls or semiconductor particles with bacterial hydrogenase led to molecular hydrogen photoproduction. Light excitation of some coenzymes, mainly NADH and NADPH, was considered from the point of view of early events of chemical evolution.Now we are interested in the creation of photobiochemical systems using principles of photosynthesis for the conversion and storage of solar energy.
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Affiliation(s)
- A A Krasnovsky
- A.N. Bakh Institute of Biochemistry, Russian Academy of Sciences, Leninsky prospect 33, 117071, Moscow, Russia
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Jennings RC, Zucchelli G, Garlaschi FM, Vianelli A. A comparison of the light-induced, non-reversible fluorescence quenching in Photosystem II with quenching due to open reaction centres in terms of the chlorophyll emission spectral forms. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1992. [DOI: 10.1016/0167-4838(92)90470-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Zucchelli G, Jennings RC, Garlaschi FM. Independent fluorescence emission of the chlorophyll spectral forms in higher plant Photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1992. [DOI: 10.1016/0005-2728(92)90214-m] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Jennings RC, Zucchelli G, Garlaschi FM. The influence of quenching by open reaction centres on the photosystem II fluorescence emission spectrum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1991. [DOI: 10.1016/s0005-2728(05)80313-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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UEHARA KAKU, MIMURO MAMORU, TANAKA MAKOTO. SPECTROSCOPIC STUDIES OF CHLOROPHYLL a AGGREGATES FORMED BY AQUEOUS DIMETHYL SULFOXIDE. Photochem Photobiol 1991. [DOI: 10.1111/j.1751-1097.1991.tb03643.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Myslinski P, Yixian L, Yizhong S, Koningstein J. Two-beam polarization studies of the ground and excited state absorption spectra of dimeric chlorophyll. J Mol Struct 1991. [DOI: 10.1016/0022-2860(91)87134-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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