1
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Ogrodzińska W, Szafran K, Łuszczyński M, Barczyk-Woźnicka O, Gabruk M. Molecular insights into the differences between cyanobacterial and plant LPORs and prolamellar body formation: In vitro studies. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 214:108935. [PMID: 39029308 DOI: 10.1016/j.plaphy.2024.108935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Revised: 07/08/2024] [Accepted: 07/12/2024] [Indexed: 07/21/2024]
Abstract
Light-dependent protochlorophyllide oxidoreductase (LPOR) has captivated the interest of the research community for decades. One reason is the photocatalytic nature of the reaction catalyzed by the enzyme, and the other is the involvement of LPOR in the formation of a paracrystalline lattice called a prolamellar body (PLB) that disintegrates upon illumination, initiating a process of photosynthetic membrane formation. In this paper, we have integrated three traditional methods previously employed to study the properties of the enzyme: molecular biology, spectroscopy, and electron microscopy. We found that for cyanobacterial LPOR, substrates binding appears to be independent of lipids, with membrane interaction primarily affecting the enzyme post-reaction, with MGDG and PG having opposite effects on SynPOR. In contrast, plant isoforms exhibit sequence alterations, rendering the enzyme effective in substrate binding mainly in the presence of anionic lipids, depending on residues at positions 122, 312, and 318. Moreover, we demonstrated that the interaction with MGDG could initially serve as enhancement of the substrate specificity towards monovinyl-protochlorophyllide (Pchlide). We have shown that the second LPOR isoforms of eudicots and monocots accumulated mutations that made these variants less and more dependent on anionic lipids, respectively. Finally, we have shown that in the presence of Pchlide, NADP+, and the lipids, plant but not cyanobacterial LPOR homolog remodel membranes into the cubic phase. The cubic phase is preserved if samples supplemented with NADP + are enriched with NADPH. The results are discussed in the evolutionary context, and the model of PLB formation is presented.
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Affiliation(s)
- Wiktoria Ogrodzińska
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Katarzyna Szafran
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Mateusz Łuszczyński
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland; Doctoral School of Exact and Natural Sciences, Jagiellonian University, Kraków, Poland
| | - Olga Barczyk-Woźnicka
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30-387, Kraków, Poland
| | - Michał Gabruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
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2
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Pesara P, Szafran K, Nguyen HC, Sirohiwal A, Pantazis DA, Gabruk M. Elucidating substrate binding in the light-dependent protochlorophyllide oxidoreductase. Chem Sci 2024; 15:7767-7780. [PMID: 38784751 PMCID: PMC11110527 DOI: 10.1039/d4sc00923a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024] Open
Abstract
The Light-Dependent Protochlorophyllide Oxidoreductase (LPOR) catalyzes a crucial step in chlorophyll biosynthesis: the rare biological photocatalytic reduction of the double C[double bond, length as m-dash]C bond in the precursor, protochlorophyllide (Pchlide). Despite its fundamental significance, limited structural insights into the active complex have hindered understanding of its reaction mechanism. Recently, a high-resolution cryo-EM structure of LPOR in its active conformation challenged our view of pigment binding, residue interactions, and the catalytic process. Surprisingly, this structure contrasts markedly with previous assumptions, particularly regarding the orientation of the bound Pchlide. To gain insights into the substrate binding puzzle, we conducted molecular dynamics simulations, quantum-mechanics/molecular-mechanics (QM/MM) calculations, and site-directed mutagenesis. Two Pchlide binding modes were considered, one aligning with historical proposals (mode A) and another consistent with the recent experimental data (mode B). Binding energy calculations revealed that in contrast to the non-specific interactions found for mode A, mode B exhibits distinct stabilizing interactions that support more thermodynamically favorable binding. A comprehensive analysis incorporating QM/MM-based local energy decomposition unraveled a complex interaction network involving Y177, H319, and the C131 carboxy group, influencing the pigment's excited state energy and potentially contributing to substrate specificity. Importantly, our results uniformly favor mode B, challenging established interpretations and emphasizing the need for a comprehensive re-evaluation of the LPOR reaction mechanism in a way that incorporates accurate structural information on pigment interactions and substrate-cofactor positioning in the binding pocket. The results shed light on the intricacies of LPOR's catalytic mechanism and provide a solid foundation for further elucidating the secrets of chlorophyll biosynthesis.
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Affiliation(s)
- Penelope Pesara
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Katarzyna Szafran
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University Gronostajowa 7 30-387 Cracow Poland
| | - Henry C Nguyen
- Department of Biochemistry & Biophysics, Quantitative Biosciences Institute, University of California San Francisco CA USA
| | - Abhishek Sirohiwal
- Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University 10691 Stockholm Sweden
| | - Dimitrios A Pantazis
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Michal Gabruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University Gronostajowa 7 30-387 Cracow Poland
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3
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Taylor A, Zhang S, Johannissen LO, Sakuma M, Phillips RS, Green AP, Hay S, Heyes DJ, Scrutton NS. Mechanistic implications of the ternary complex structural models for the photoenzyme protochlorophyllide oxidoreductase. FEBS J 2024; 291:1404-1421. [PMID: 38060334 DOI: 10.1111/febs.17025] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/13/2023] [Accepted: 12/05/2023] [Indexed: 04/04/2024]
Abstract
The photoenzyme protochlorophyllide oxidoreductase (POR) is an important enzyme for understanding biological H-transfer mechanisms. It uses light to catalyse the reduction of protochlorophyllide to chlorophyllide, a key step in chlorophyll biosynthesis. Although a wealth of spectroscopic data have provided crucial mechanistic insight, a structural rationale for POR photocatalysis has proved challenging and remains hotly debated. Recent structural models of the ternary enzyme-substrate complex, derived from crystal and electron microscopy data, show differences in the orientation of the protochlorophyllide substrate and the architecture of the POR active site, with significant implications for the catalytic mechanism. Here, we use a combination of computational and experimental approaches to investigate the compatibility of each structural model with the hypothesised reaction mechanisms and propose an alternative structural model for the cyanobacterial POR ternary complex. We show that a strictly conserved tyrosine, previously proposed to act as the proton donor in POR photocatalysis, is unlikely to be involved in this step of the reaction but is crucial for Pchlide binding. Instead, an active site cysteine is important for both hydride and proton transfer reactions in POR and is proposed to act as the proton donor, either directly or through a water-mediated network. Moreover, a conserved glutamine is important for Pchlide binding and ensuring efficient photochemistry by tuning its electronic properties, likely by interacting with the central Mg atom of the substrate. This optimal 'binding pose' for the POR ternary enzyme-substrate complex illustrates how light energy can be harnessed to facilitate enzyme catalysis by this unique enzyme.
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Affiliation(s)
- Aoife Taylor
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Shaowei Zhang
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Linus O Johannissen
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Michiyo Sakuma
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Robert S Phillips
- Departments of Chemistry and Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
| | - Anthony P Green
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Sam Hay
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Derren J Heyes
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology and Department of Chemistry, School of Natural Sciences, Faculty of Science and Engineering, The University of Manchester, UK
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4
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Liu R, Wang L, Meng Y, Tian Y, Li F, Lu H. Theoretical and Experimental Studies on Plant Light-Dependent Protochlorophyllide Oxidoreductase as a Novel Target for Searching Potential Herbicides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023. [PMID: 37467369 DOI: 10.1021/acs.jafc.3c01783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Herbicide resistance is a prevalent problem that has posed a foremost challenge to crop production worldwide. Light-dependent enzyme NADPH: protochlorophyllide oxidoreductase (LPOR) in plants is a metabolic target that could satisfy this unmet demand. Herein, for the first time, we embarked on proposing a new mode of action of herbicides by performing structure-based virtual screening targeting multiple LPOR binding sites, with the determination of further bioactivity on the lead series. The feasibility of exploiting high selectivity and safety herbicides targeting LPOR was discussed from the perspective of the origin and phylogeny. Besides, we revealed the structural rearrangement and the selection key for NADPH cofactor binding to LPOR. Based on these, multitarget virtual screening was performed and the result identified compounds 2 affording micromolar inhibition, in which the IC50 reached 4.74 μM. Transcriptome analysis revealed that compound 2 induced more genes related to chlorophyll synthesis in Arabidopsis thaliana, especially the LPOR genes. Additionally, we clarified that these compounds binding to the site enhanced the overall stability and local rigidity of the complex systems from molecular dynamics simulation. This study delivers a guideline on how to assess activity-determining features of inhibitors to LPOR and how to translate this knowledge into the design of novel and effective inhibitors against malignant weed that act by targeting LPOR.
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Affiliation(s)
- Ruiyuan Liu
- College of Science, China Agricultural University, Beijing 100193, China
| | - Leng Wang
- College of Science, China Agricultural University, Beijing 100193, China
| | - Yue Meng
- College of Science, China Agricultural University, Beijing 100193, China
| | - Yiyi Tian
- College of Science, China Agricultural University, Beijing 100193, China
| | - Fang Li
- College of Science, China Agricultural University, Beijing 100193, China
| | - Huizhe Lu
- College of Science, China Agricultural University, Beijing 100193, China
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5
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Kim DH, Lim SH, Lee JY. Expression of RsPORB Is Associated with Radish Root Color. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12112214. [PMID: 37299194 DOI: 10.3390/plants12112214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/18/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023]
Abstract
Radish (Raphanus sativus) plants exhibit varied root colors due to the accumulation of chlorophylls and anthocyanins compounds that are beneficial for both human health and visual quality. The mechanisms of chlorophyll biosynthesis have been extensively studied in foliar tissues but remain largely unknown in other tissues. In this study, we examined the role of NADPH:protochlorophyllide oxidoreductases (PORs), which are key enzymes in chlorophyll biosynthesis, in radish roots. The transcript level of RsPORB was abundantly expressed in green roots and positively correlated with chlorophyll content in radish roots. Sequences of the RsPORB coding region were identical between white (948) and green (847) radish breeding lines. Additionally, virus-induced gene silencing assay with RsPORB exhibited reduced chlorophyll contents, verifying that RsPORB is a functional enzyme for chlorophyll biosynthesis. Sequence comparison of RsPORB promoters from white and green radishes showed several insertions and deletions (InDels) and single-nucleotide polymorphisms. Promoter activation assays using radish root protoplasts verified that InDels of the RsPORB promoter contribute to its expression level. These results suggested that RsPORB is one of the key genes underlying chlorophyll biosynthesis and green coloration in non-foliar tissues, such as roots.
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Affiliation(s)
- Da-Hye Kim
- Division of Horticultural Biotechnology, School of Biotechnology, Hankyong National University, Anseong 17579, Republic of Korea
- Research Institute of International Technology and Information, Hankyong National University, Anseong 17579, Republic of Korea
| | - Sun-Hyung Lim
- Division of Horticultural Biotechnology, School of Biotechnology, Hankyong National University, Anseong 17579, Republic of Korea
- Research Institute of International Technology and Information, Hankyong National University, Anseong 17579, Republic of Korea
| | - Jong-Yeol Lee
- National Institute of Agricultural Sciences, Rural Development Administration, Jeonju 54874, Republic of Korea
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6
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Sameer H, Victor G, Katalin S, Henrik A. Elucidation of ligand binding and dimerization of NADPH:protochlorophyllide (Pchlide) oxidoreductase from pea (Pisum sativum L.) by structural analysis and simulations. Proteins 2021; 89:1300-1314. [PMID: 34021929 DOI: 10.1002/prot.26151] [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: 09/09/2020] [Revised: 02/18/2021] [Accepted: 05/11/2021] [Indexed: 11/07/2022]
Abstract
NADPH:protochlorophyllide (Pchlide) oxidoreductase (POR) is a key enzyme of chlorophyll biosynthesis in angiosperms. It is one of few known photoenzymes, which catalyzes the light-activated trans-reduction of the C17-C18 double bond of Pchlide's porphyrin ring. Due to the light requirement, dark-grown angiosperms cannot synthesize chlorophyll. No crystal structure of POR is available, so to improve understanding of the protein's three-dimensional structure, its dimerization, and binding of ligands (both the cofactor NADPH and substrate Pchlide), we computationally investigated the sequence and structural relationships among homologous proteins identified through database searches. The results indicate that α4 and α7 helices of monomers form the interface of POR dimers. On the basis of conserved residues, we predicted 11 functionally important amino acids that play important roles in POR binding to NADPH. Structural comparison of available crystal structures revealed that they participate in formation of binding pockets that accommodate the Pchlide ligand, and that five atoms of the closed tetrapyrrole are involved in non-bonding interactions. However, we detected no clear pattern in the physico-chemical characteristics of the amino acids they interact with. Thus, we hypothesize that interactions of these atoms in the Pchlide porphyrin ring are important to hold the ligand within the POR binding site. Analysis of Pchlide binding in POR by molecular docking and PELE simulations revealed that the orientation of the nicotinamide group is important for Pchlide binding. These findings highlight the complexity of interactions of porphyrin-containing ligands with proteins, and we suggest that fit-inducing processes play important roles in POR-Pchlide interactions.
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Affiliation(s)
- Hassan Sameer
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Guallar Victor
- ICREA, Passeig Lluís Companys 23, Barcelona, Spain
- Barcelona Supercomputing Center (BSC), Barcelona, Spain
| | - Solymosi Katalin
- Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, Budapest, Hungary
| | - Aronsson Henrik
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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7
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Solymosi K, Mysliwa-Kurdziel B. The Role of Membranes and Lipid-Protein Interactions in the Mg-Branch of Tetrapyrrole Biosynthesis. FRONTIERS IN PLANT SCIENCE 2021; 12:663309. [PMID: 33995458 PMCID: PMC8113382 DOI: 10.3389/fpls.2021.663309] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/22/2021] [Indexed: 05/31/2023]
Abstract
Chlorophyll (Chl) is essential for photosynthesis and needs to be produced throughout the whole plant life, especially under changing light intensity and stress conditions which may result in the destruction and elimination of these pigments. All steps of the Mg-branch of tetrapyrrole biosynthesis leading to Chl formation are carried out by enzymes associated with plastid membranes. Still the significance of these protein-membrane and protein-lipid interactions in Chl synthesis and chloroplast differentiation are not very well-understood. In this review, we provide an overview on Chl biosynthesis in angiosperms with emphasis on its association with membranes and lipids. Moreover, the last steps of the pathway including the reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide), the biosynthesis of the isoprenoid phytyl moiety and the esterification of Chlide are also summarized. The unique biochemical and photophysical properties of the light-dependent NADPH:protochlorophyllide oxidoreductase (LPOR) enzyme catalyzing Pchlide photoreduction and located to peculiar tubuloreticular prolamellar body (PLB) membranes of light-deprived tissues of angiosperms and to envelope membranes, as well as to thylakoids (especially grana margins) are also reviewed. Data about the factors influencing tubuloreticular membrane formation within cells, the spectroscopic properties and the in vitro reconstitution of the native LPOR enzyme complexes are also critically discussed.
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Affiliation(s)
- Katalin Solymosi
- Department of Plant Anatomy, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Beata Mysliwa-Kurdziel
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
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8
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Nguyen HC, Melo AA, Kruk J, Frost A, Gabruk M. Photocatalytic LPOR forms helical lattices that shape membranes for chlorophyll synthesis. NATURE PLANTS 2021; 7:437-444. [PMID: 33875834 DOI: 10.1038/s41477-021-00885-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 02/19/2021] [Indexed: 05/21/2023]
Abstract
Chlorophyll biosynthesis, crucial to life on Earth, is tightly regulated because its precursors are phototoxic1. In flowering plants, the enzyme light-dependent protochlorophyllide oxidoreductase (LPOR) captures photons to catalyse the penultimate reaction: the reduction of a double bond within protochlorophyllide (Pchlide) to generate chlorophyllide (Chlide)2,3. In darkness, LPOR oligomerizes to facilitate photon energy transfer and catalysis4,5. However, the complete three-dimensional structure of LPOR, the higher-order architecture of LPOR oligomers and the implications of these self-assembled states for catalysis, including how LPOR positions Pchlide and the co-factor NADPH, remain unknown. Here, we report the atomic structure of LPOR assemblies by electron cryo-microscopy. LPOR polymerizes with its substrates into helical filaments around constricted lipid bilayer tubes. Portions of LPOR and Pchlide insert into the outer membrane leaflet, targeting the product, Chlide, to the membrane for the final reaction site of chlorophyll biosynthesis. In addition to its crucial photocatalytic role, we show that in darkness LPOR filaments directly shape membranes into high-curvature tubules with the spectral properties of the prolamellar body, whose light-triggered disassembly provides lipids for thylakoid assembly. Moreover, our structure of the catalytic site challenges previously proposed reaction mechanisms6. Together, our results reveal a new and unexpected synergy between photosynthetic membrane biogenesis and chlorophyll synthesis in plants, orchestrated by LPOR.
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Affiliation(s)
- Henry C Nguyen
- Department of Biochemistry & Biophysics, Quantitative Biosciences Institute, University of California, San Francisco, CA, USA.
- Asher Biotherapeutics, South San Francisco, CA, USA.
| | - Arthur A Melo
- Department of Biochemistry & Biophysics, Quantitative Biosciences Institute, University of California, San Francisco, CA, USA
| | - Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Adam Frost
- Department of Biochemistry & Biophysics, Quantitative Biosciences Institute, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
| | - Michal Gabruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
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9
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Heyes DJ, Zhang S, Taylor A, Johannissen LO, Hardman SJO, Hay S, Scrutton NS. Photocatalysis as the 'master switch' of photomorphogenesis in early plant development. NATURE PLANTS 2021; 7:268-276. [PMID: 33686224 DOI: 10.1038/s41477-021-00866-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Enzymatic photocatalysis is seldom used in biology. Photocatalysis by light-dependent protochlorophyllide oxidoreductase (LPOR)-one of only a few natural light-dependent enzymes-is an exception, and is responsible for the conversion of protochlorophyllide to chlorophyllide in chlorophyll biosynthesis. Photocatalysis by LPOR not only regulates the biosynthesis of the most abundant pigment on Earth but it is also a 'master switch' in photomorphogenesis in early plant development. Following illumination, LPOR promotes chlorophyll production, plastid membranes are transformed and the photosynthetic apparatus is established. Given these remarkable, light-induced pigment and morphological changes, the LPOR-catalysed reaction has been extensively studied from catalytic, physiological and plant development perspectives, highlighting vital, and multiple, cellular roles of this intriguing enzyme. Here, we offer a perspective in which the link between LPOR photocatalysis and plant photomorphogenesis is explored. Notable breakthroughs in LPOR structural biology have uncovered the structural-mechanistic basis of photocatalysis. These studies have clarified how photon absorption by the pigment protochlorophyllide-bound in a ternary LPOR-protochlorophyllide-NADPH complex-triggers photocatalysis and a cascade of complex molecular and cellular events that lead to plant morphological changes. Photocatalysis is therefore the master switch responsible for early-stage plant development and ultimately life on Earth.
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Affiliation(s)
- Derren J Heyes
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK.
| | - Shaowei Zhang
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Aoife Taylor
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Linus O Johannissen
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Samantha J O Hardman
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Sam Hay
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, Manchester, UK.
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10
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Zhang S, Godwin ARF, Taylor A, Hardman SJO, Jowitt TA, Johannissen LO, Hay S, Baldock C, Heyes DJ, Scrutton NS. Dual role of the active site 'lid' regions of protochlorophyllide oxidoreductase in photocatalysis and plant development. FEBS J 2020; 288:175-189. [PMID: 32866986 DOI: 10.1111/febs.15542] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/15/2020] [Accepted: 08/24/2020] [Indexed: 11/29/2022]
Abstract
Protochlorophyllide oxidoreductase (POR) catalyses reduction of protochlorophyllide (Pchlide) to chlorophyllide, a light-dependent reaction of chlorophyll biosynthesis. POR is also important in plant development as it is the main constituent of prolamellar bodies in etioplast membranes. Prolamellar bodies are highly organised, paracrystalline structures comprising aggregated oligomeric structures of POR-Pchlide-NADPH complexes. How these oligomeric structures are formed and the role of Pchlide in oligomerisation remains unclear. POR crystal structures highlight two peptide regions that form a 'lid' to the active site, and undergo conformational change on binding Pchlide. Here, we show that Pchlide binding triggers formation of large oligomers of POR using size exclusion chromatography. A POR 'octamer' has been isolated and its structure investigated by cryo-electron microscopy at 7.7 Å resolution. This structure shows that oligomer formation is most likely driven by the interaction of amino acid residues in the highly conserved lid regions. Computational modelling indicates that Pchlide binding stabilises exposure of hydrophobic surfaces formed by the lid regions, which supports POR dimerisation and ultimately oligomer formation. Studies with variant PORs demonstrate that lid residues are involved in substrate binding and photocatalysis. These highly conserved lid regions therefore have a dual function. The lid residues position Pchlide optimally to enable photocatalysis. Following Pchlide binding, they also enable POR oligomerisation - a process that is reversed through subsequent photocatalysis in the early stages of chloroplast development.
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Affiliation(s)
- Shaowei Zhang
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Alan R F Godwin
- Wellcome Centre for Cell-Matrix Research, University of Manchester, UK.,Division of Cell-Matrix Biology and Regenerative Medicine, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, UK
| | - Aoife Taylor
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Samantha J O Hardman
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Thomas A Jowitt
- Wellcome Centre for Cell-Matrix Research, University of Manchester, UK.,Division of Cell-Matrix Biology and Regenerative Medicine, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, UK
| | - Linus O Johannissen
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Sam Hay
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Clair Baldock
- Wellcome Centre for Cell-Matrix Research, University of Manchester, UK.,Division of Cell-Matrix Biology and Regenerative Medicine, Faculty of Biology, Medicine and Health, School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, UK
| | - Derren J Heyes
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, The University of Manchester, UK.,Department of Chemistry, Faculty of Science and Engineering, School of Natural Sciences, The University of Manchester, UK
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11
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Schmermund L, Bierbaumer S, Schein VK, Winkler CK, Kara S, Kroutil W. Extending the Library of Light‐Dependent Protochlorophyllide Oxidoreductases and their Solvent Tolerance, Stability in Light and Cofactor Flexibility. ChemCatChem 2020. [DOI: 10.1002/cctc.202000561] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Luca Schmermund
- Institute of Chemistry University of Graz – Field of Excellence BioHealth NAWI Graz BioTechMed Graz Heinrichstrasse 28 8010 Graz Austria
| | - Sarah Bierbaumer
- Institute of Chemistry University of Graz – Field of Excellence BioHealth NAWI Graz BioTechMed Graz Heinrichstrasse 28 8010 Graz Austria
| | - Viktor K. Schein
- Institute of Chemistry University of Graz – Field of Excellence BioHealth NAWI Graz BioTechMed Graz Heinrichstrasse 28 8010 Graz Austria
| | - Christoph K. Winkler
- Institute of Chemistry University of Graz – Field of Excellence BioHealth NAWI Graz BioTechMed Graz Heinrichstrasse 28 8010 Graz Austria
| | - Selin Kara
- Department of Engineering Biological and Chemical Engineering Biocatalysis and Bioprocessing Group Aarhus University Gustav Wieds Vej 10 8000 Aarhus Denmark
| | - Wolfgang Kroutil
- Institute of Chemistry University of Graz – Field of Excellence BioHealth NAWI Graz BioTechMed Graz Heinrichstrasse 28 8010 Graz Austria
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12
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Crystal structures of cyanobacterial light-dependent protochlorophyllide oxidoreductase. Proc Natl Acad Sci U S A 2020; 117:8455-8461. [PMID: 32234783 DOI: 10.1073/pnas.1920244117] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The reduction of protochlorophyllide (Pchlide) to chlorophyllide (Chlide) is the penultimate step of chlorophyll biosynthesis. In oxygenic photosynthetic bacteria, algae, and plants, this reaction can be catalyzed by the light-dependent Pchlide oxidoreductase (LPOR), a member of the short-chain dehydrogenase superfamily sharing a conserved Rossmann fold for NAD(P)H binding and the catalytic activity. Whereas modeling and simulation approaches have been used to study the catalytic mechanism of this light-driven reaction, key details of the LPOR structure remain unclear. We determined the crystal structures of LPOR from two cyanobacteria, Synechocystis sp. PCC 6803 and Thermosynechococcus elongatus Structural analysis defines the LPOR core fold, outlines the LPOR-NADPH interaction network, identifies the residues forming the substrate cavity and the proton-relay path, and reveals the role of the LPOR-specific loop. These findings provide a basis for understanding the structure-function relationships of the light-driven Pchlide reduction.
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13
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Structural basis for enzymatic photocatalysis in chlorophyll biosynthesis. Nature 2019; 574:722-725. [PMID: 31645759 DOI: 10.1038/s41586-019-1685-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 09/25/2019] [Indexed: 12/26/2022]
Abstract
The enzyme protochlorophyllide oxidoreductase (POR) catalyses a light-dependent step in chlorophyll biosynthesis that is essential to photosynthesis and, ultimately, all life on Earth1-3. POR, which is one of three known light-dependent enzymes4,5, catalyses reduction of the photosensitizer and substrate protochlorophyllide to form the pigment chlorophyllide. Despite its biological importance, the structural basis for POR photocatalysis has remained unknown. Here we report crystal structures of cyanobacterial PORs from Thermosynechococcus elongatus and Synechocystis sp. in their free forms, and in complex with the nicotinamide coenzyme. Our structural models and simulations of the ternary protochlorophyllide-NADPH-POR complex identify multiple interactions in the POR active site that are important for protochlorophyllide binding, photosensitization and photochemical conversion to chlorophyllide. We demonstrate the importance of active-site architecture and protochlorophyllide structure in driving POR photochemistry in experiments using POR variants and protochlorophyllide analogues. These studies reveal how the POR active site facilitates light-driven reduction of protochlorophyllide by localized hydride transfer from NADPH and long-range proton transfer along structurally defined proton-transfer pathways.
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14
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Schneidewind J, Krause F, Bocola M, Stadler AM, Davari MD, Schwaneberg U, Jaeger KE, Krauss U. Consensus model of a cyanobacterial light-dependent protochlorophyllide oxidoreductase in its pigment-free apo-form and photoactive ternary complex. Commun Biol 2019; 2:351. [PMID: 31583285 PMCID: PMC6761149 DOI: 10.1038/s42003-019-0590-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/29/2019] [Indexed: 12/02/2022] Open
Abstract
Photosynthetic organisms employ two different enzymes for the reduction of the C17 = C18 double bond of protochlorophyllide (Pchlide), yielding the chlorophyll precursor chlorophyllide. First, a nitrogenase-like, light-independent (dark-operative) Pchlide oxidoreductase and secondly, a light-dependent Pchlide oxidoreductase (LPOR). For the latter enzyme, despite decades of research, no structural information is available. Here, we use protein structure modelling, molecular dynamics (MD) simulations combined with multi-wavelength analytical ultracentrifugation (MWA-AUC) and small angle X-ray scattering (SAXS) experiments to derive a consensus model of the LPOR apoprotein and the substrate/cofactor/LPOR ternary complex. MWA-AUC and SAXS experiments independently demonstrate that the apoprotein is monomeric, while ternary complex formation induces dimerization. SAXS-guided modelling studies provide a full-length model of the apoprotein and suggest a tentative mode of dimerization for the LPOR ternary complex, supported by published cross-link constraints. Our study provides a first impression of the LPOR structural organization.
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Affiliation(s)
- Judith Schneidewind
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Frank Krause
- Nanolytics, Gesellschaft für Kolloidanalytik GmbH, Am Mühlenberg 11, 14476 Potsdam, Germany
| | - Marco Bocola
- Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany
| | - Andreas Maximilian Stadler
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1), Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Mehdi D. Davari
- Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany
| | - Ulrich Schwaneberg
- Lehrstuhl für Biotechnologie, RWTH Aachen University, Worringerweg 3, 52074 Aachen, Germany
- DWI-Leibniz Institut für Interaktive Materialien, Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Karl-Erich Jaeger
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- IBG-1: Biotechnologie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - Ulrich Krauss
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
- IBG-1: Biotechnologie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
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15
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Stadler AM, Schneidewind J, Zamponi M, Knieps-Grünhagen E, Gholami S, Schwaneberg U, Rivalta I, Garavelli M, Davari MD, Jaeger KE, Krauss U. Ternary Complex Formation and Photoactivation of a Photoenzyme Results in Altered Protein Dynamics. J Phys Chem B 2019; 123:7372-7384. [PMID: 31380636 DOI: 10.1021/acs.jpcb.9b06608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The interplay between protein dynamics and catalysis remains a fundamental question in enzymology. We here investigate the ns-timescale dynamics of a light-dependent NADPH:protochlorophyllide oxidoreductase (LPOR), a photoenzyme crucial for chlorophyll synthesis. LPORs catalyze the light-triggered trans addition of a hydride and a proton across the C17═C18 double bond of the chlorophyll precursor protochlorophyllide (Pchlide). Because of the lack of an LPOR structure, the global structural and dynamic consequences of LPOR/Pchlide/NADPH ternary complex formation remain elusive. Moreover, photoactivation of LPORs by low-light preillumination is controversially discussed as unequivocal proof for this phenomenon is lacking. By employing quasielastic neutron spectroscopy (QENS), we show that the formation of the ternary holoprotein complex as well as photoactivation lead to progressive rigidification of the protein. These findings are supported by thermostability measurements, which reveal different melting behavior and thermostabilities for the apo- and holoprotein ternary complexes. Molecular dynamics simulations in good agreement with the experimental QENS results suggest that the increased flexibility observed for the apoprotein stems from structural fluctuations of the NADPH and Pchlide substrate binding sites of the enzyme. On the basis of our results, in conjunction with activity and stability measurements, we provide independent proof for LPOR photoactivation, defined as a process that modifies the protein structure and dynamics, resulting in an increased substrate turnover. Our findings advance the structural and dynamic understanding of LPORs and provide a first link between protein dynamics and catalysis for this enzyme class.
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Affiliation(s)
| | | | - Michaela Zamponi
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ) , Forschungszentrum Jülich GmbH , Lichtenbergstr. 1 , 85748 Garching , Germany
| | | | - Samira Gholami
- Dipartimento di Chimica Industriale , Università degli Studi di Bologna , Viale del Risorgimento 4 , I-40136 Bologna , Italy
| | - Ulrich Schwaneberg
- Institute of Biotechnology , RWTH Aachen University , Worringer Weg 3 , D-52074 Aachen , Germany.,DWI-Leibniz Institute for Interactive Materials , Forckenbeckstraße 50 , 52056 Aachen , Germany
| | - Ivan Rivalta
- Université de Lyon, École Normale Supérieure de Lyon, CNRS, Université Claude Bernard Lyon 1, Laboratoire de Chimie UMR 5182 , F-69342 Lyon , France
| | - Marco Garavelli
- Dipartimento di Chimica Industriale , Università degli Studi di Bologna , Viale del Risorgimento 4 , I-40136 Bologna , Italy.,École Normale Supérieure de Lyon, CNRS, Laboratoire de Chimie UMR 5182, Université de Lyon , 46 Allée d'Italie , F-69364 Lyon Cedex 07 , France
| | - Mehdi D Davari
- Institute of Biotechnology , RWTH Aachen University , Worringer Weg 3 , D-52074 Aachen , Germany
| | - Karl-Erich Jaeger
- IBG-1: Biotechnologie , Forschungszentrum Jülich GmbH , D-52425 Jülich , Germany
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16
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Schmermund L, Jurkaš V, Özgen FF, Barone GD, Büchsenschütz HC, Winkler CK, Schmidt S, Kourist R, Kroutil W. Photo-Biocatalysis: Biotransformations in the Presence of Light. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00656] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Luca Schmermund
- Institute of Chemistry, University of Graz, NAWI Graz, BioTechMed Graz, BioHealth, Heinrichstrasse 28, 8010 Graz, Austria
| | - Valentina Jurkaš
- Institute of Chemistry, University of Graz, NAWI Graz, BioTechMed Graz, BioHealth, Heinrichstrasse 28, 8010 Graz, Austria
| | - F. Feyza Özgen
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, Petersgasse 14, 8010 Graz, Austria
| | - Giovanni D. Barone
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, Petersgasse 14, 8010 Graz, Austria
| | - Hanna C. Büchsenschütz
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, Petersgasse 14, 8010 Graz, Austria
| | - Christoph K. Winkler
- Institute of Chemistry, University of Graz, NAWI Graz, BioTechMed Graz, BioHealth, Heinrichstrasse 28, 8010 Graz, Austria
| | - Sandy Schmidt
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, Petersgasse 14, 8010 Graz, Austria
| | - Robert Kourist
- Institute of Molecular Biotechnology, Graz University of Technology, NAWI Graz, Petersgasse 14, 8010 Graz, Austria
| | - Wolfgang Kroutil
- Institute of Chemistry, University of Graz, NAWI Graz, BioTechMed Graz, BioHealth, Heinrichstrasse 28, 8010 Graz, Austria
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17
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Erdei AL, Kósa A, Böddi B. Distinct UV-A or UV-B irradiation induces protochlorophyllide photoreduction and bleaching in dark-grown pea (Pisum sativum L.) epicotyls. PHOTOSYNTHESIS RESEARCH 2019; 140:93-102. [PMID: 30225812 DOI: 10.1007/s11120-018-0584-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 09/12/2018] [Indexed: 06/08/2023]
Abstract
The effects of distinct UV-A and UV-B radiations were studied on etiolated pea (Pisum sativum L.) epicotyls. Emission spectra of the native protochlorophyll and protochlorophyllide forms were measured when epicotyls were excited with 360 or 300 nm light. The UV-A (360 nm) excited mainly the non-enzyme-bound monomers of protochlorophyll and protochlorophyllide and the UV-B (300 nm) excited preferentially the flash-photoactive protochlorophyllide complexes. These latter complexes converted into short- and long-wavelength chlorophyllide forms at 10-s illumination with both wavelength irradiations. As the spectral changes were very small, the effects of longer illumination periods were studied. Room temperature fluorescence emission spectra were measured from the same epicotyl spots before and after irradiation with various wavelengths between 280 and 360 nm for 15 min and the "illuminated" minus "dark" difference spectra were calculated. Both the UV-A and the UV-B irradiations caused photoreduction of protochlorophyllide into chlorophyllide. At 10 µmol photons m-2 s-1, the photoreduction rates were similar, however, at 60 µmol photons m-2 s-1, the UV-B irradiation was more effective in inducing chlorophyllide formation than the UV-A. The action spectra of protochlorophyllide plus protochlorophyll loss and chlorophyllide production showed that the radiation around 290 nm was the most effective in provoking protochlorophyllide photoreduction and the UV light above 320 nm caused strong bleaching. These results show that the effect of the UV radiation should be considered when discussing the protochlorophyllide-chlorophyllide photoreduction during germination and as a part of the regeneration of the photosynthetic apparatus proceeding in the daily run of photosynthesis.
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Affiliation(s)
- Anna Laura Erdei
- Department of Plant Anatomy, Faculty of Science, Institute of Biology, ELTE Eötvös Loránd University, Pázmány P. s. 1/c, Budapest, 1117, Hungary
- Department of Zoology, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Annamária Kósa
- Department of Plant Anatomy, Faculty of Science, Institute of Biology, ELTE Eötvös Loránd University, Pázmány P. s. 1/c, Budapest, 1117, Hungary
| | - Béla Böddi
- Department of Plant Anatomy, Faculty of Science, Institute of Biology, ELTE Eötvös Loránd University, Pázmány P. s. 1/c, Budapest, 1117, Hungary.
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18
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Gholami S, Nenov A, Rivalta I, Bocola M, Bordbar AK, Schwaneberg U, Davari MD, Garavelli M. Theoretical Model of the Protochlorophyllide Oxidoreductase from a Hierarchy of Protocols. J Phys Chem B 2018; 122:7668-7681. [PMID: 29996651 DOI: 10.1021/acs.jpcb.8b04231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The enzyme protochlorophyllide oxidoreductase (LPOR) catalyzes the light-driven reduction of protochlorophyllide (Pchlide), a crucial step in chlorophyll biosynthesis. Molecular understanding of the photocatalytic mechanism of LPOR is essential for harnessing light energy to mediate enzymatic reactions. The absence of X-ray crystal structure has promoted the development of LPOR homology models that lack a catalytically competent active site and could not explain the variously reported spectroscopic evidence, including time-resolved optical spectroscopy data. We have refined previous structural models to account for the catalytic active site and the characteristic experimental spectral features of Pchlide binding, including the 26 cm-1 red shift of the C13(1) carbonyl stretch vibration in the mid-infrared (IR) and the 12 nm red shift of the Q x electronic band. A hierarchy of theoretical methods, including homology modeling, molecular dynamics simulations, hybrid quantum mechanics [(TD-)DFT]/molecular mechanics [AMBER] calculations, and computational vibrational and electronic spectroscopies, have been combined in an iterative protocol to reproduce experimental evidence and to predict ultrafast transient IR spectroscopic fingerprints associated with the catalytic process. The successful application to the LPOR enzyme indicates that the presented hierarchical protocol provides a general workflow to protein structure refinement.
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Affiliation(s)
- Samira Gholami
- Department of Chemistry , University of Isfahan , Isfahan 81746-73441 , Iran.,Dipartimento di Chimica Industriale , Università degli Studi di Bologna , Viale del Risorgimento 4 , I-40136 Bologna , Italy
| | - Artur Nenov
- Dipartimento di Chimica Industriale , Università degli Studi di Bologna , Viale del Risorgimento 4 , I-40136 Bologna , Italy
| | - Ivan Rivalta
- Université de Lyon , École Normale Supérieure de Lyon, CNRS, Université Claude Bernard Lyon 1, Laboratoire de Chimie UMR 5182, F-69342 , Lyon , France
| | - Marco Bocola
- Institute of Biotechnology , RWTH Aachen University , Worringer Weg 3 , 52074 Aachen , Germany
| | - A Khalegh Bordbar
- Department of Chemistry , University of Isfahan , Isfahan 81746-73441 , Iran
| | - Ulrich Schwaneberg
- Institute of Biotechnology , RWTH Aachen University , Worringer Weg 3 , 52074 Aachen , Germany.,DWI-Leibniz Institute for Interactive Materials , Forckenbeckstraße 50 , 52056 Aachen , Germany
| | - Mehdi D Davari
- Institute of Biotechnology , RWTH Aachen University , Worringer Weg 3 , 52074 Aachen , Germany
| | - Marco Garavelli
- Dipartimento di Chimica Industriale , Università degli Studi di Bologna , Viale del Risorgimento 4 , I-40136 Bologna , Italy
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19
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Yang LY, Yang SL, Li JY, Ma JH, Pang T, Zou CM, He B, Gong M. Effects of different growth temperatures on growth, development, and plastid pigments metabolism of tobacco (Nicotiana tabacum L.) plants. BOTANICAL STUDIES 2018; 59:5. [PMID: 29404808 PMCID: PMC5799153 DOI: 10.1186/s40529-018-0221-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 01/27/2018] [Indexed: 05/04/2023]
Abstract
BACKGROUND Temperature remarkably affects the growth and metabolism of plants. Tobacco is an important cash crop, and the long-term effects of different growth temperatures (18.5, 23.5 and 28.5 °C, daily average) on growth, development and plastid pigments metabolism of tobacco plants were investigated in this study. RESULTS Compared with tobacco plants grown under 23.5 °C, treatments with 18.5 and 28.5 °C inhibited the expansion of leaves. The contents of superoxide anion (O 2·- ), hydrogen peroxide (H2O2) and malonaldehyde (MDA) in the leaves were significantly increased under 28.5 °C from 0 to 60 days, which in turn accelerated the flowering and senescence of tobacco plants. By contrast, the treatment with 18.5 °C remarkably decreased O 2.- , H2O2 and MDA, and delayed the flowering and senescence. Furthermore, treatment with 18.5 °C significantly up-regulated the expression of glutamyl-tRNA reductase (Glu-TR) and magnesium chelatase (MgCH), and down-regulated the ferri chelatase (FeCH), protochlorophyllide oxidoreductase, chlorophyllase (CHLase), phaeophorbide a monooxygenase (PaO) and phytoene synthase (PSY), which further promoted the accumulation of chlorophyll (Chls) and reduced the carotenoids (Cars) in leaves. On the contrary, exposing to 28.5 °C remarkably down-regulated the Glu-TR and MgCH, and up-regulated the FeCH, CHLase, PaO and PSY, which in turn decreased the Chls and increased the Cars in tobacco leaves. CONCLUSION As compared with the plants grown under 23.5 °C, lower (18.5 °C) and higher (28.5 °C) growth temperature inhibited the growth of tobacco plants. In general, treatment with 28.5 °C accelerated the flowering and senescence of tobacco plants by enhancing the accumulation of O 2.- and H2O2 in leaves, while exposing to 18.5 °C had the opposite effects. Treatment with 18.5 °C increased the content of Chls and reduced the Cars in leaves. In contrast, Treatment with 28.5 °C decreased the Chls and increased the Cars. Moreover, both O 2.- and H2O2 took part in the breakdown of Chls in tobacco leaves to some extent. The results suggest that growth temperature could regulate growth, development, and plastid pigments metabolism, and 23.5 °C could be an optimal temperature for growth, development and metabolism of plastid pigments of tobacco plants under the experimental conditions.
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Affiliation(s)
- Li Yun Yang
- School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University, Kunming, 650500 People’s Republic of China
| | - Shuang Long Yang
- School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University, Kunming, 650500 People’s Republic of China
| | - Jun Ying Li
- Yunnan Academy of Tobacco Agricultural Sciences, Kunming, 650031 People’s Republic of China
| | - Jun Hong Ma
- Yunnan Academy of Tobacco Agricultural Sciences, Kunming, 650031 People’s Republic of China
| | - Tao Pang
- Yunnan Academy of Tobacco Agricultural Sciences, Kunming, 650031 People’s Republic of China
| | - Cong Ming Zou
- Yunnan Academy of Tobacco Agricultural Sciences, Kunming, 650031 People’s Republic of China
| | - Bin He
- Yunnan Tobacco Leaf Company, Kunming, 650218 People’s Republic of China
| | - Ming Gong
- School of Life Sciences, Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Key Laboratory of Biomass Energy and Environmental Biotechnology of Yunnan Province, Yunnan Normal University, Kunming, 650500 People’s Republic of China
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20
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MGDG, PG and SQDG regulate the activity of light-dependent protochlorophyllide oxidoreductase. Biochem J 2017; 474:1307-1320. [PMID: 28188256 DOI: 10.1042/bcj20170047] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/07/2017] [Accepted: 02/10/2017] [Indexed: 11/17/2022]
Abstract
Light-dependent protochlorophyllide oxidoreductase (POR) is a plant enzyme involved in the chlorophyll biosynthesis pathway. POR reduces one of the double bonds of the protochlorophyllide (Pchlide) using NADPH and light. In the present study, we found out that phosphatidylglycerol and sulfoquinovosyl diacylglycerol are allosteric regulators of the nucleotide binding, which increase the affinity towards NADPH a 100-fold. Moreover, we showed for the first time that NADH can, like NADPH, form active complexes with Pchlide and POR, however, at much higher concentrations. Additionally, monogalactosyldiacylglycerol (MGDG) was shown to be the main factor responsible for the red shift of the fluorescence emission maximum of Pchlide:POR:NADPH complexes. Importantly, the emission maximum at 654 nm was obtained only for the reaction mixtures supplemented with MGDG and at least one of the negatively charged plant lipids. Moreover, the site-directed mutagenesis allowed us to identify amino acid residues that may be responsible for lipid binding and Pchlide coordination. Our experiments allowed us to identify six different Pchlide:POR complexes that differ in the fluorescence emission maxima of the pigment. The results presented here reveal the contribution of thylakoid lipids in the regulation of the chlorophyll biosynthesis pathway; however, the molecular mechanisms of this process are to be clarified.
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