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Yang Z, Li F, Shen S, Wang X, Nihmot Ibrahim A, Zheng H, Zhang J, Ji X, Liao X, Zhang Y. Natural chlorophyll: a review of analysis methods, health benefits, and stabilization strategies. Crit Rev Food Sci Nutr 2024:1-15. [PMID: 38795062 DOI: 10.1080/10408398.2024.2356259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2024]
Abstract
Chlorophyll (Chl) is a natural pigment, widely distributed ranging from photosynthetic prokaryotes to higher plants, with an annual yield of up to 1.2 billion tons worldwide. Five types of Chls are observed in nature, that can be distinguished and identified using spectroscopy and mass spectrometry. Chl is also used in the food industry owing to its bioactivities, including obesity prevention, inflammation reduction, viral infection inhibition, anticancer effects, anti-oxidation, and immunostimulatory properties. It has great potential of being applied as a colorant and dietary supplement in the food industry. However, Chl is unstable under various enzymatic, acidic, heat, and light conditions, which limit its application. Although some strategies, such as aggregation with other food components, microencapsulation, and metal cation replacement, have been proposed to overcome these limitations, they are still not enough to facilitate its widespread application. Therefore, stabilization strategies and bioactivities of Chl need to be expected to expand its application in various fields, thereby aiding in the sustainable development of mankind.
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Affiliation(s)
- Zhaotian Yang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
- Sanya Institute of China Agricultural University, Sanya, PR China
| | - Fangwei Li
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
- College of Food Science and Engineering, Ocean University of China, Qingdao, PR China
| | - Suxia Shen
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Xiao Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Ajibola Nihmot Ibrahim
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Hongli Zheng
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Jinghao Zhang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Xingyu Ji
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
| | - Yan Zhang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, PR China
- National Engineering Research Center for Fruits and Vegetables Processing Ministry of Science and Technology, China Agricultural University, Beijing, PR China
- Key Laboratory of Fruits and Vegetables Processing Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, PR China
- Sanya Institute of China Agricultural University, Sanya, PR China
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2
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Riedl M, Renger T, Seibt J. Theory of 2D electronic spectroscopy of water soluble chlorophyll-binding protein (WSCP): Signatures of Chl b derivate. J Chem Phys 2024; 160:184114. [PMID: 38726933 DOI: 10.1063/5.0200876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 04/21/2024] [Indexed: 06/29/2024] Open
Abstract
We investigate how electronic excitations and subsequent dissipative dynamics in the water soluble chlorophyll-binding protein (WSCP) are connected to features in two-dimensional (2D) electronic spectra, thereby comparing results from our theoretical approach with experimental data from the literature. Our calculations rely on third-order response functions, which we derived from a second-order cumulant expansion of the dissipative dynamics involving the partial ordering prescription, assuming a fast vibrational relaxation in the potential energy surfaces of excitons. Depending on whether the WSCP complex containing a tetrameric arrangement of pigments composed of two dimers with weak excitonic coupling between them binds the chlorophyll variant Chl a or Chl b, the resulting linear absorption and circular dichroism spectra and particularly the 2D spectra exhibit substantial differences in line shapes. These differences between Chl a WSCP and Chl b WSCP cannot be explained by the slightly modified excitonic couplings within the two variants. In the case of Chl a WSCP, the assumption of equivalent dimer subunits facilitates a reproduction of substantial features from the experiment by the calculations. In contrast, for Chl b WSCP, we have to assume that the sample, in addition to Chl b dimers, contains a small but distinct fraction of chemically modified Chl b pigments. The existence of such Chl b derivates has been proposed by Pieper et al. [J. Phys. Chem. B 115, 4042 (2011)] based on low-temperature absorption and hole-burning spectroscopy. Here, we provide independent evidence.
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Affiliation(s)
- Michael Riedl
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
| | - Thomas Renger
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
| | - Joachim Seibt
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria
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3
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Cherepanov DA, Milanovsky GE, Neverov KV, Obukhov YN, Maleeva YV, Aybush AV, Kritsky MS, Nadtochenko VA. Exciton interactions of chlorophyll tetramer in water-soluble chlorophyll-binding protein BoWSCP. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 309:123847. [PMID: 38217986 DOI: 10.1016/j.saa.2024.123847] [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: 07/31/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/15/2024]
Abstract
The exciton interaction of four chlorophyll a (Chl a) molecules in a symmetrical tetrameric complex of the water-soluble chlorophyll-binding protein BoWSCP was analyzed in the pH range of 3-11. Exciton splitting ΔE = 232 ± 2 cm-1 of the Qy band of Chl a into two subcomponents with relative intensities of 78.1 ± 0.7 % and 21.9 ± 0.7 % was determined by a joint decomposition of the absorption and circular dichroism spectra into Gaussian functions. The exciton coupling parameters were calculated based on the BoWSCP atomic structure in three approximations: the point dipole model, the distributed atomic monopoles, and direct ab initio calculations in the TDDFT/PCM approximation. The Coulomb interactions of monomers were calculated within the continuum model using three values of optical permittivity. The models based on the properties of free Chl a in solution suffer from significant errors both in estimating the absolute value of the exciton interaction and in the relative intensity of exciton transitions. Calculations within the TDDFT/PCM approximation reproduce the experimentally determined parameters of the exciton splitting and the relative intensities of the exciton bands. The following factors of pigment-protein and pigment-pigment interactions were examined: deviation of the macrocycle geometry from the planar conformation of free Chl; the formation of hydrogen bonds between the macrocycle and water molecules; the overlap of wave functions of monomers at close distances. The most significant factor is the geometrical deformation of the porphyrin macrocycle, which leads to an increase in the dipole moment of Chl monomer from 5.5 to 6.9 D and to a rotation of the dipole moment by 15° towards the cyclopentane ring. The contributions of resonant charge-transfer states to the wave functions of the Chl dimer were determined and the transition dipole moments of the symmetric and antisymmetric charge-transfer states were estimated.
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Affiliation(s)
- D A Cherepanov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Kosygina str., 4, Russian Federation; A.N. Belozersky Institute Of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Leninskye gory, 1b.40, Russian Federation.
| | - G E Milanovsky
- A.N. Belozersky Institute Of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Leninskye gory, 1b.40, Russian Federation
| | - K V Neverov
- A.N. Bach Institute of Biochemistry, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences", 119071 Moscow, Leninsky prospect, 33b.2, Russian Federation; Faculty of Biology, Moscow State University, 119234 Moscow, Leninskye gory, 1b.12, Russian Federation
| | - Yu N Obukhov
- A.N. Bach Institute of Biochemistry, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences", 119071 Moscow, Leninsky prospect, 33b.2, Russian Federation
| | - Yu V Maleeva
- Faculty of Biology, Moscow State University, 119234 Moscow, Leninskye gory, 1b.12, Russian Federation
| | - A V Aybush
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Kosygina str., 4, Russian Federation
| | - M S Kritsky
- A.N. Bach Institute of Biochemistry, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences", 119071 Moscow, Leninsky prospect, 33b.2, Russian Federation
| | - V A Nadtochenko
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Kosygina str., 4, Russian Federation; Department of Chemistry, Moscow State University, 119991 Moscow, Leninskye gory, 1b.3, Russian Federation
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Bouargalne Y, Guilbaud F, Macherel D, Delalande O, Deleu C, Le Cahérec F. Brassica napus Drought-Induced 22-kD Protein (BnD22) Acts Simultaneously as a Cysteine Protease Inhibitor and Chlorophyll-Binding Protein. PLANT & CELL PHYSIOLOGY 2023; 64:536-548. [PMID: 36905393 DOI: 10.1093/pcp/pcad016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/20/2023] [Accepted: 03/09/2023] [Indexed: 05/17/2023]
Abstract
Class II water-soluble chlorophyll proteins (WSCPs) from Brassicaceae are non-photosynthetic proteins that bind with chlorophyll (Chl) and its derivatives. The physiological function of WSCPs is still unclear, but it is assumed to be involved in stress responses, which is likely related to their Chl-binding and protease inhibition (PI) activities. Yet, the dual function and simultaneous functionality of WSCPs must still be better understood. Here, the biochemical functions of Brassica napus drought-induced 22-kDa protein (BnD22), a major WSCP expressed in B. napus leaves, were investigated using recombinant hexahistidine-tagged protein. We showed that BnD22 inhibited cysteine proteases, such as papain, but not serine proteases. BnD22 was able to bind with Chla or Chlb to form tetrameric complexes. Unexpectedly, BnD22-Chl tetramer displays higher inhibition toward cysteine proteases, indicating (i) simultaneous Chl-binding and PI activities and (ii) Chl-dependent activation of PI activity of BnD22. Moreover, the photostability of BnD22-Chl tetramer was reduced upon binding with the protease. Using three-dimensional structural modeling and molecular docking, we revealed that Chl binding favors interaction between BnD22 and proteases. Despite its Chl-binding ability, the BnD22 was not detected in chloroplasts but rather in the endoplasmic reticulum and vacuole. In addition, the C-terminal extension peptide of BnD22, which cleaved off post-translationally in vivo, was not implicated in subcellular localization. Instead, it drastically promoted the expression, solubility and stability of the recombinant protein.
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Affiliation(s)
| | - Florian Guilbaud
- IGEPP, INRAE, Institut Agro, Université Rennes, Rennes 35000, France
| | - David Macherel
- IRHS, INRAE, Institut Agro, Université Angers, Angers 49000, France
| | | | - Carole Deleu
- IGEPP, INRAE, Institut Agro, Université Rennes, Rennes 35000, France
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5
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LHC-like Proteins: The Guardians of Photosynthesis. Int J Mol Sci 2023; 24:ijms24032503. [PMID: 36768826 PMCID: PMC9916820 DOI: 10.3390/ijms24032503] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 02/03/2023] Open
Abstract
The emergence of chlorophyll-containing light-harvesting complexes (LHCs) was a crucial milestone in the evolution of photosynthetic eukaryotic organisms. Light-harvesting chlorophyll-binding proteins form complexes in proximity to the reaction centres of photosystems I and II and serve as an antenna, funnelling the harvested light energy towards the reaction centres, facilitating photochemical quenching, thereby optimizing photosynthesis. It is now generally accepted that the LHC proteins evolved from LHC-like proteins, a diverse family of proteins containing up to four transmembrane helices. Interestingly, LHC-like proteins do not participate in light harvesting to elevate photosynthesis activity under low light. Instead, they protect the photosystems by dissipating excess energy and taking part in non-photochemical quenching processes. Although there is evidence that LHC-like proteins are crucial factors of photoprotection, the roles of only a few of them, mainly the stress-related psbS and lhcSR, are well described. Here, we summarize the knowledge gained regarding the evolution and function of the various LHC-like proteins, with emphasis on those strongly related to photoprotection. We further suggest LHC-like proteins as candidates for improving photosynthesis in significant food crops and discuss future directions in their research.
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6
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Bouargalne Y, Raguénès-Nicol C, Guilbaud F, Cheron A, Clouet V, Deleu C, Le Cahérec F. New insights into chlorophyll-WSCP (water-soluble chlorophyll proteins) interactions : The case study of BnD22 (Brassica napus drought-induced 22 kDa). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 181:71-80. [PMID: 35452956 DOI: 10.1016/j.plaphy.2022.03.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/01/2022] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
The water-soluble chlorophyll-proteins (WSCP) of class II from Brassicaceae are non-photosynthetic proteins that bind chlorophylls (Chls) and chlorophyll derivatives. Their physiological roles, biochemical functions and mode of action are still unclear. It is assumed that the WSCPs have a protection function against Chl photodamage during stressful conditions. WSCPs are subdivided into class IIA and class IIB according to their apparent Chla/b binding ratio. Although their Chla/Chlb binding selectivity has been partly characterized, their Chl affinities are not yet precisely defined. For instance, WSCPs IIA do not show any Chl binding preference while WSCPs IIB have greater affinity to Chlb. In this study, we present a novel method for assessment of Chl binding to WSCPs based on the differences of Chl photobleaching rates in a large range of Chl/protein ratios. The protein we have chosen to study WSCP is BnD22, a WSCP IIA induced in the leaves of Brassica napus under water deficit. BnD22 formed oligomeric complexes upon binding to Chla and/or Chlb allowing a protective effect against photodamage. The binding constants indicate that BnD22 binds with high affinity the Chls and with a strong selectivity to Chla. Moreover, dependending of Chl/protein ratio upon reconstitution, two distinct binding events were detected resulting from difference of Chl stoichiometry inside oligomeric complexes.
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Affiliation(s)
- Youssef Bouargalne
- Univ Rennes 1, INRAE, Institut Agro, IGEPP - UMR 1349, 35653, Le Rheu, France
| | | | - Florian Guilbaud
- Univ Rennes 1, INRAE, Institut Agro, IGEPP - UMR 1349, 35653, Le Rheu, France
| | | | - Vanessa Clouet
- Univ Rennes 1, INRAE, Institut Agro, IGEPP - UMR 1349, 35653, Le Rheu, France
| | - Carole Deleu
- Univ Rennes 1, INRAE, Institut Agro, IGEPP - UMR 1349, 35653, Le Rheu, France
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7
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Li M, Park BM, Dai X, Xu Y, Huang J, Sun F. Controlling synthetic membraneless organelles by a red-light-dependent singlet oxygen-generating protein. Nat Commun 2022; 13:3197. [PMID: 35680863 PMCID: PMC9184582 DOI: 10.1038/s41467-022-30933-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/19/2022] [Indexed: 12/05/2022] Open
Abstract
Membraneless organelles (MLOs) formed via protein phase separation have great implications for both physiological and pathological processes. However, the inability to precisely control the bioactivities of MLOs has hindered our understanding of their roles in biology, not to mention their translational applications. Here, by combining intrinsically disordered domains such as RGG and mussel-foot proteins, we create an in cellulo protein phase separation system, of which various biological activities can be introduced via metal-mediated protein immobilization and further controlled by the water-soluble chlorophyll protein (WSCP)—a remarkably stable, red-light-responsive singlet oxygen generator. The WSCP-laden protein condensates undergo a liquid-to-solid phase transition on light exposure, due to oxidative crosslinking, providing a means to control catalysis within synthetic MLOs. Moreover, these photoresponsive condensates, which retain the light-induced phase-transition behavior in living cells, exhibit marked membrane localization, reminiscent of the semi-membrane-bound compartments like postsynaptic densities in nervous systems. Together, this engineered system provides an approach toward controllable synthetic MLOs and, alongside its light-induced phase transition, may well serve to emulate and explore the aging process at the subcellular or even molecular level. Membraneless organelles play vital cellular roles, and control over their formation and state could have varied applications. Here, the authors develop photoresponsive synthetic condensates whose activity can be controlled through the use of light to trigger liquid-to-solid phase transition.
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Affiliation(s)
- Manjia Li
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Byung Min Park
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xin Dai
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.,Laboratory for Synthetic Chemistry and Chemical Biology, Health@InnoHK, Hong Kong Science Park, Hong Kong, China
| | - Yingjie Xu
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.,Greater Bay Biomedical InnoCenter, Shenzhen Bay Laboratory, Shenzhen, 518036, China
| | - Jinqing Huang
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Fei Sun
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China. .,Greater Bay Biomedical InnoCenter, Shenzhen Bay Laboratory, Shenzhen, 518036, China. .,Biomedical Research Institute, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, 518036, China. .,HKUST Shenzhen Research Institute, Shenzhen, 518057, China.
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8
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Hydrophobic interaction driving the binding of soybean protein isolate and chlorophyll: Improvements to the thermal stability of chlorophyll. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2020.106465] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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9
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Lahav Y, Noy D, Schapiro I. Spectral tuning of chlorophylls in proteins - electrostatics vs. ring deformation. Phys Chem Chem Phys 2021; 23:6544-6551. [PMID: 33690760 DOI: 10.1039/d0cp06582j] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In photosynthetic complexes, tuning of chlorophyll light-absorption spectra by the protein environment is crucial to their efficiency and robustness. Recombinant type II water soluble chlorophyll-binding proteins from Brassicaceae (WSCPs) are useful for studying spectral tuning mechanisms due to their symmetric homotetramer structure, and the ability to rigorously modify the chlorophyll's protein surroundings. Our previous comparison of the crystal structures of two WSCP homologues suggested that protein-induced chlorophyll ring deformation is the predominant spectral tuning mechanism. Here, we implement a more rigorous analysis based on hybrid quantum mechanics and molecular mechanics calculations to quantify the relative contributions of geometrical and electrostatic factors to the absorption spectra of WSCP-chlorophyll complexes. We show that when considering conformational dynamics, geometry distortions such as chlorophyll ring deformation accounts for about one-third of the spectral shift, whereas the direct polarization of the electron density accounts for the remaining two-thirds. From a practical perspective, protein electrostatics is easier to manipulate than chlorophyll conformations, thus, it may be more readily implemented in designing artificial protein-chlorophyll complexes.
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Affiliation(s)
- Yigal Lahav
- Fritz Haber Centre for Molecular Dynamics Research, Institute of Chemistry, Hebrew University of Jerusalem, Israel.
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10
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Bednarczyk D, Tor-Cohen C, Das PK, Noy D. Direct Assembly in Aqueous Solutions of Stable Chlorophyllide Complexes with Type II Water-soluble Chlorophyll Proteins. Photochem Photobiol 2021; 97:732-738. [PMID: 33570189 DOI: 10.1111/php.13398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 02/08/2021] [Indexed: 01/28/2023]
Abstract
Water-soluble chlorophyll-binding proteins (WSCPs) from Brassicaceae constitute a small family of non-photosynthetic proteins that may provide a useful benchmark and model system for studying molecular aspects of chlorophyll-protein interactions such as the tuning of absorption and emission spectra, and binding selectivity. WSCP apo-proteins are readily expressed by recombinant DNA techniques and can be assembled in vitro with natural and synthetic chlorophyll derivatives. The complexes with native chlorophylls are exceptionally stable toward thermal dissociation and protein denaturation due to hydrophobic interactions with the chlorophyll's phytyl chains that stabilize the core of the WSCP tetrameric complexes. However, assembly requires the use of detergents or water-in-oil emulsions to introduce the hydrophobic pigments into the water-soluble apo-proteins. Here, we explore the direct assembly of recombinant WSCPs with the water-soluble phytyl-free chlorophyll analogue chlorophyllide a in aqueous solutions. We show that the complexes formed by mixing chlorophyllide and WSCP apo-proteins are exclusively tetrameric, and while they lack the extreme thermostability of the respective chlorophyll complexes, they are still thermostable up to around 60°C. Their absorption and CD spectra are very similar to the chlorophyll complexes albeit slight peak shifts and broadening of the bands indicate variations in pigment and protein conformations, and less rigid structures. Simplifying the assembly process of WSCPs opens new possibilities for their use in modelling natural chlorophyll-protein complexes, and as templates for designing novel artificial protein-pigment complexes.
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Affiliation(s)
- Dominika Bednarczyk
- Migal-Galilee Research Institute, Kiryat Shmona, Israel.,Agricultural Research Organization, Volcani Center, Rishon Lezyion, Israel
| | | | | | - Dror Noy
- Migal-Galilee Research Institute, Kiryat Shmona, Israel.,Faculty of Sciences and Technology, Tel-Hai Academic College, Upper Galilee, Israel
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11
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Ohtsuki T, Uchida A, Nishigaki A, Nagashima U, Takahashi S, Ohshima S. Excitonic Energy Level of Homo- and Hetero-Dimers and Their Composition in the Native Water-Soluble Chlorophyll Protein from Lepidium Virginicum. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200243] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Takayuki Ohtsuki
- Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Akira Uchida
- Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Atsuko Nishigaki
- Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Umpei Nagashima
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa, Yokohama, Kanagawa 236-0027, Japan
| | | | - Shigeru Ohshima
- Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
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12
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Reimers JR, Rätsep M, Freiberg A. Asymmetry in the Q y Fluorescence and Absorption Spectra of Chlorophyll a Pertaining to Exciton Dynamics. Front Chem 2020; 8:588289. [PMID: 33344415 PMCID: PMC7738624 DOI: 10.3389/fchem.2020.588289] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/26/2020] [Indexed: 11/13/2022] Open
Abstract
Significant asymmetry found between the high-resolution Qy emission and absorption spectra of chlorophyll-a is herein explained, providing basic information needed to understand photosynthetic exciton transport and photochemical reactions. The Qy spectral asymmetry in chlorophyll has previously been masked by interference in absorption from the nearby Qx transition, but this effect has recently been removed using extensive quantum spectral simulations or else by analytical inversion of absorption and magnetic circular dichroism data, allowing high-resolution absorption information to be accurately determined from fluorescence-excitation spectra. To compliment this, here, we measure and thoroughly analyze the high-resolution differential fluorescence line narrowing spectra of chlorophyll-a in trimethylamine and in 1-propanol. The results show that vibrational frequencies often change little between absorption and emission, yet large changes in line intensities are found, this effect also being strongly solvent dependent. Among other effects, the analysis in terms of four basic patterns of Duschinsky-rotation matrix elements, obtained using CAM-B3LYP calculations, predicts that a chlorophyll-a molecule excited into a specific vibrational level, may, without phase loss or energy relaxation, reemit the light over a spectral bandwidth exceeding 1,000 cm−1 (0.13 eV) to influence exciton-transport dynamics.
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Affiliation(s)
- Jeffrey R Reimers
- School of Chemistry, The University of Sydney, Sydney, NSW, Australia
| | - Margus Rätsep
- Institute of Physics, University of Tartu, Tartu, Estonia
| | - Arvi Freiberg
- Institute of Physics, University of Tartu, Tartu, Estonia.,Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
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13
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Agostini A, Büchel C, Di Valentin M, Carbonera D. A distinctive pathway for triplet-triplet energy transfer photoprotection in fucoxanthin chlorophyll-binding proteins from Cyclotella meneghiniana. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148310. [PMID: 32991847 DOI: 10.1016/j.bbabio.2020.148310] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 11/29/2022]
Abstract
Fucoxanthin chlorophyll-binding proteins (FCPs) are the major light-harvesting complexes of diatoms. In this work, FCPs isolated from Cyclotella meneghiniana have been studied by means of optically detected magnetic resonance (ODMR) and time-resolved electron paramagnetic resonance (TR-EPR), with the aim to characterize the photoprotective mechanism based on triplet-triplet energy transfer (TTET). The spectroscopic properties of the chromophores carrying the triplet state have been interpreted on the basis of a delved analysis of the recently solved crystallographic structures of FCP. The results point toward a photoprotective role for two fucoxanthin molecules exposed to the exterior of the FCP monomers. This shows that FCP has adopted a structural strategy different from that of related light-harvesting complexes from plants and other microalgae, in which the photoprotective role is carried out by two highly conserved carotenoids in the interior of the complex.
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Affiliation(s)
- Alessandro Agostini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.
| | - Claudia Büchel
- Institute of Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Marilena Di Valentin
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.
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14
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Girr P, Paulsen H. How water-soluble chlorophyll protein extracts chlorophyll from membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183479. [PMID: 32961122 DOI: 10.1016/j.bbamem.2020.183479] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/25/2020] [Accepted: 09/15/2020] [Indexed: 10/23/2022]
Abstract
Water-soluble chlorophyll proteins (WSCPs) found in Brassicaceae are non-photosynthetic proteins that bind only a small number of chlorophylls. Their biological function remains unclear, but recent data indicate that WSCPs are involved in stress response and pathogen defense as producers of reactive oxygen species and/or Chl-regulated protease inhibitors. For those functions, WSCP apoprotein supposedly binds Chl to become physiologically active or inactive, respectively. Thus, Chl-binding seems to be a pivotal step for the biological function of WSCP. WSCP can extract Chl from the thylakoid membrane but little is known about the mechanism of how Chl is sequestered from the membrane into the binding sites. Here, we investigate the interaction of WSCP with the thylakoid membrane in detail. The extraction of Chl from the thylakoid by WSCP apoprotein is a slow and inefficient reaction, because WSCP presumably does not directly extract Chl from other Chl-binding proteins embedded in the membrane. WSCP apoprotein interacts with model membranes that contain the thylakoid lipids MGDG, DGDG or PG, and can extract Chl from those. Furthermore, the WSCP-Chl complex, once formed, no longer interacts with membranes. We concluded that the surroundings of the WSCP pigment-binding site are involved in the WSCP-membrane interaction and identified a ring of hydrophobic amino acids with two conserved Trp residues around the Chl-binding site. Indeed, WSCP variants, in which one of the Trp residues was exchanged for Phe, still interact with the membrane but are no longer able to extract Chl.
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Affiliation(s)
- Philipp Girr
- Institute of Molecular Physiology, Johannes-Gutenberg University Mainz, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes-Gutenberg University Mainz, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany.
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15
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Leiger K, Linnanto JM, Freiberg A. Establishment of the Qy Absorption Spectrum of Chlorophyll a Extending to Near-Infrared. Molecules 2020; 25:molecules25173796. [PMID: 32825445 PMCID: PMC7503670 DOI: 10.3390/molecules25173796] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 02/06/2023] Open
Abstract
A weak absorption tail related to the Qy singlet electronic transition of solvated chlorophyll a is discovered using sensitive anti-Stokes fluorescence excitation spectroscopy. The quasi-exponentially decreasing tail was, at ambient temperature, readily observable as far as -2400 cm-1 from the absorption peak and at relative intensity of 10-7. The tail also weakened rapidly upon cooling the sample, implying its basic thermally activated nature. The shape of the spectrum as well as its temperature dependence were qualitatively well reproduced by quantum chemical calculations involving the pigment intramolecular vibrational modes, their overtones, and pairwise combination modes, but no intermolecular/solvent modes. A similar tail was observed earlier in the case of bacteriochlorophyll a, suggesting generality of this phenomenon. Long vibronic red tails are, thus, expected to exist in all pigments of light-harvesting relevance at physiological temperatures.
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Affiliation(s)
- Kristjan Leiger
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 51011 Tartu, Estonia; (K.L.); (J.M.L.)
| | - Juha Matti Linnanto
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 51011 Tartu, Estonia; (K.L.); (J.M.L.)
| | - Arvi Freiberg
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 51011 Tartu, Estonia; (K.L.); (J.M.L.)
- Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51014 Tartu, Estonia
- Estonian Academy of Sciences, Kohtu 6, 10130 Tallinn, Estonia
- Correspondence:
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16
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Girr P, Kilper J, Pohland AC, Paulsen H. The pigment binding behaviour of water-soluble chlorophyll protein (WSCP). Photochem Photobiol Sci 2020; 19:695-712. [PMID: 32338263 DOI: 10.1039/d0pp00043d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/17/2020] [Indexed: 12/17/2023]
Abstract
Water-soluble chlorophyll proteins (WSCPs) are homotetrameric proteins that bind four chlorophyll (Chl) molecules in identical binding sites, which makes WSCPs a good model to study protein-pigment interactions. In a previous study, we described preferential binding of Chl a or Chl b in various WSCP versions. Chl b binding is preferred when a hydrogen bond can be formed between the C7 formyl of the chlorin macrocycle and the protein, whereas Chl a is preferred when Chl b binding is sterically unfavorable. Here, we determined the binding affinities and kinetics of various WSCP versions not only for Chl a/b, but also for chlorophyllide (Chlide) a/b and pheophytin (Pheo) a/b. Altered KD values are responsible for the Chl a/b selectivity in WSCP whereas differences in the reaction kinetics are neglectable in explaining different Chl a/b preferences. WSCP binds both Chlide and Pheo with a lower affinity than Chl, which indicates the importance of the phytol chain and the central Mg2+ ion as interaction sites between WSCP and pigment. Pheophorbide (Pheoide), lacking both the phytol chain and the central Mg2+ ion, can only be bound as Pheoide b to a WSCP that has a higher affinity for Chl b than Chl a, which underlines the impact of the C7 formyl-protein interaction. Moreover, WSCP was able to bind protochlorophyllide and Mg-protoporphyrin IX, which suggests that neither the size of the π electron system of the macrocycle nor the presence of a fifth ring at the macrocycle notably affect the binding to WSCP. WSCP also binds heme to form a tetrameric complex, suggesting that heme is bound in the Chl-binding site.
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Affiliation(s)
- Philipp Girr
- Institute of Molecular Physiology, Johannes Gutenberg-University Mainz, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Jessica Kilper
- Institute of Molecular Physiology, Johannes Gutenberg-University Mainz, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Anne-Christin Pohland
- Institute of Molecular Physiology, Johannes Gutenberg-University Mainz, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes Gutenberg-University Mainz, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany.
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17
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Fresch E, Meneghin E, Agostini A, Paulsen H, Carbonera D, Collini E. How the Protein Environment Can Tune the Energy, the Coupling, and the Ultrafast Dynamics of Interacting Chlorophylls: The Example of the Water-Soluble Chlorophyll Protein. J Phys Chem Lett 2020; 11:1059-1067. [PMID: 31952446 PMCID: PMC7995254 DOI: 10.1021/acs.jpclett.9b03628] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The interplay between active molecules and the protein environment in light-harvesting complexes tunes the photophysics and the dynamical properties of pigment-protein complexes in a subtle way, which is not fully understood. Here we characterized the photophysics and the ultrafast dynamics of four variants of the water-soluble chlorophyll protein (WSCP) as an ideal model system to study the behavior of strongly interacting chlorophylls. We found that when coordinated by the WSCP protein, the presence of the formyl group in chlorophyll b replacing the methyl group in chlorophyll a strongly affects the exciton energy and the dynamics of the system, opening up the possibility of tuning the photophysics and the transport properties of multichromophores by engineering specific interactions with the surroundings.
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Affiliation(s)
- Elisa Fresch
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Elena Meneghin
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Alessandro Agostini
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
- Institute
of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Harald Paulsen
- Institute
of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Donatella Carbonera
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
| | - Elisabetta Collini
- Department
of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padua, Italy
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18
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Lemke O, Götze JP. On the Stability of the Water-Soluble Chlorophyll-Binding Protein (WSCP) Studied by Molecular Dynamics Simulations. J Phys Chem B 2019; 123:10594-10604. [PMID: 31702165 DOI: 10.1021/acs.jpcb.9b07915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The water-soluble chlorophyll-binding protein (WSCP) is assumed to be not a part of the photosynthetic process. Applying molecular dynamics (MD) simulations, we aimed to obtain insight into the exceptional stability of WSCP. We analyzed dynamical features such as the hydrogen bond network, flexibility, and force distributions. The WSCP structure contains two cysteines at the interfaces of every protein chain, which are in close contact with the cysteines of the other dimer. We tested if a connection of these cysteines between different protein chains influences the dynamical behavior to investigate any influences on the thermal stability. We find that the hydrogen bond network is very stable regardless of the presence or absence of the hypothetical disulfide bridges and/or the chlorophyll units. Furthermore, it is found that the phytyl chains of the chlorophyll units are extremely flexible, much more than what is seen in crystal structures. Nonetheless, they seem to protect a photochemically active site of the chlorophylls over the complete simulation time. Finally, we also find that a cavity in the chlorophyll-surrounding sheath exists, which may allow access for individual small molecules to the core of WSCP.
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Affiliation(s)
- Oliver Lemke
- Department of Chemistry and Biochemistry , Freie Universität Berlin , Arnimallee 22 , 14195 Berlin , Germany
| | - Jan P Götze
- Department of Chemistry and Biochemistry , Freie Universität Berlin , Arnimallee 22 , 14195 Berlin , Germany
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19
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Agostini A, Meneghin E, Gewehr L, Pedron D, Palm DM, Carbonera D, Paulsen H, Jaenicke E, Collini E. How water-mediated hydrogen bonds affect chlorophyll a/b selectivity in Water-Soluble Chlorophyll Protein. Sci Rep 2019; 9:18255. [PMID: 31796824 PMCID: PMC6890793 DOI: 10.1038/s41598-019-54520-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 11/14/2019] [Indexed: 01/15/2023] Open
Abstract
The Water-Soluble Chlorophyll Protein (WSCP) of Brassicaceae is a remarkably stable tetrapyrrole-binding protein that, by virtue of its simple design, is an exceptional model to investigate the interactions taking place between pigments and their protein scaffold and how they affect the photophysical properties and the functionality of the complexes. We investigated variants of WSCP from Lepidium virginicum (Lv) and Brassica oleracea (Bo), reconstituted with Chlorophyll (Chl) b, to determine the mechanisms by which the different Chl binding sites control their Chl a/b specificities. A combined Raman and crystallographic investigation has been employed, aimed to characterize in detail the hydrogen-bond network involving the formyl group of Chl b. The study revealed a variable degree of conformational freedom of the hydrogen bond networks among the WSCP variants, and an unexpected mixed presence of hydrogen-bonded and not hydrogen-bonded Chls b in the case of the L91P mutant of Lv WSCP. These findings helped to refine the description of the mechanisms underlying the different Chl a/b specificities of WSCP versions, highlighting the importance of the structural rigidity of the Chl binding site in the vicinity of the Chl b formyl group in granting a strong selectivity to binding sites.
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Affiliation(s)
- Alessandro Agostini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy. .,Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany.
| | - Elena Meneghin
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Lucas Gewehr
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Danilo Pedron
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Daniel M Palm
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes Gutenberg-University, Johannes-von-Müller-Weg 6, 55128, Mainz, Germany
| | - Elmar Jaenicke
- Institute of Molecular Physiology, Johannes Gutenberg-University, Jakob-Welder-Weg 26, 55128, Mainz, Germany
| | - Elisabetta Collini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131, Padova, Italy.
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20
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Rätsep M, Linnanto JM, Muru R, Biczysko M, Reimers JR, Freiberg A. Absorption-emission symmetry breaking and the different origins of vibrational structures of the 1Qy and 1Qx electronic transitions of pheophytin a. J Chem Phys 2019; 151:165102. [DOI: 10.1063/1.5116265] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Margus Rätsep
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia
| | - Juha Matti Linnanto
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia
| | - Renata Muru
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia
| | - Malgorzata Biczysko
- International Centre for Quantum and Molecular Structures and Department of Physics, Shanghai University, Shanghai 200444, China
| | - Jeffrey R. Reimers
- International Centre for Quantum and Molecular Structures and Department of Physics, Shanghai University, Shanghai 200444, China
- School of Mathematical and Physical Sciences, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Arvi Freiberg
- Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia and Institute of Molecular and Cell Biology, University of Tartu, Riia 23, 51010 Tartu, Estonia
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21
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Agostini A, Dal Farra MG, Paulsen H, Polimeno A, Orian L, Di Valentin M, Carbonera D. Similarity and Specificity of Chlorophyll b Triplet State in Comparison to Chlorophyll a as Revealed by EPR/ENDOR and DFT Calculations. J Phys Chem B 2019; 123:8232-8239. [DOI: 10.1021/acs.jpcb.9b07912] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Alessandro Agostini
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
- Institute of Molecular Physiology, Johannes Gutenberg University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Maria Giulia Dal Farra
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes Gutenberg University, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Antonino Polimeno
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Laura Orian
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Marilena Di Valentin
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
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