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Erhart T, Nadegger C, Vergeiner S, Kreutz C, Müller T, Kräutler B. Novel Types of Phyllobilins in a Fern - Molecular Reporters of the Evolution of Chlorophyll Breakdown in the Paleozoic Era. Chemistry 2024; 30:e202401288. [PMID: 38634697 DOI: 10.1002/chem.202401288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 04/19/2024]
Abstract
Breakdown of chlorophyll (Chl), as studied in angiosperms, follows the pheophorbide a oxygenase/phyllobilin (PaO/PB) pathway, furnishing linear tetrapyrroles, named phyllobilins (PBs). In an investigation with fern leaves we have discovered iso-phyllobilanones (iPBs) with an intriguingly rearranged and oxidized carbon skeleton. We report here a key second group of iPBs from the fern and on their structure analysis. Previously, these additional Chl-catabolites escaped their characterization, since they exist in aqueous media as mixtures of equilibrating isomers. However, their chemical dehydration furnished stable iPB-derivatives that allowed the delineation of the enigmatic structures and chemistry of the original natural catabolites. The structures of all fern-iPBs reflect the early core steps of a PaO/PB-type pathway and the PB-to-iPB carbon skeleton rearrangement. A striking further degradative chemical ring-cleavage was observed, proposed to consume singlet molecular oxygen (1O2). Hence, Chl-catabolites may play a novel active role in detoxifying cellular 1O2. The critical deviations from the PaO/PB pathway, found in the fern, reflect evolutionary developments of Chl-breakdown in the green plants in the Paleozoic era.
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Affiliation(s)
- Theresia Erhart
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
| | - Christian Nadegger
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
| | - Stefan Vergeiner
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
| | - Thomas Müller
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
| | - Bernhard Kräutler
- Institute of Organic Chemistry and Center for Molecular Biosciences, University of Innsbruck, 6020, Innsbruck, Austria
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Karg CA, Taniguchi M, Lindsey JS, Moser S. Phyllobilins - Bioactive Natural Products Derived from Chlorophyll - Plant Origins, Structures, Absorption Spectra, and Biomedical Properties. PLANTA MEDICA 2023; 89:637-662. [PMID: 36198325 DOI: 10.1055/a-1955-4624] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Phyllobilins are open-chain products of the biological degradation of chlorophyll a in higher plants. Recent studies reveal that phyllobilins exert anti-oxidative and anti-inflammatory properties, as well as activities against cancer cells, that contribute to the human health benefits of numerous plants. In general, phyllobilins have been overlooked in phytochemical analyses, and - more importantly - in the analyses of medicinal plant extracts. Nevertheless, over the past three decades, > 70 phyllobilins have been identified upon examination of more than 30 plant species. Eight distinct chromophoric classes of phyllobilins are known: phyllolumibilins (PluBs), phylloleucobilins (PleBs), phylloxanthobilins (PxBs), and phylloroseobilins (PrBs)-each in type-I or type-II groups. Here, we present a database of absorption and fluorescence spectra that has been compiled of 73 phyllobilins to facilitate identification in phytochemical analyses. The spectra are provided in digital form and can be viewed and downloaded at www.photochemcad.com. The present review describes the plant origin, molecular structure, and absorption and fluorescence features of the 73 phyllobilins, along with an overview of key medicinal properties. The review should provide an enabling tool for the community for the straightforward identification of phyllobilins in plant extracts, and the foundation for deeper understanding of these ubiquitous but underexamined plant-derived micronutrients for human health.
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Affiliation(s)
- Cornelia A Karg
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilian University of Munich, Germany
| | | | | | - Simone Moser
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilian University of Munich, Germany
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Taniguchi M, Lindsey JS. Absorption and Fluorescence Spectra of Open-chain Tetrapyrrole Pigments–Bilirubins, Biliverdins, Phycobilins, and Synthetic Analogues. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C: PHOTOCHEMISTRY REVIEWS 2023. [DOI: 10.1016/j.jphotochemrev.2023.100585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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Jo M, Knapp M, Boggs DG, Brimberry M, Donnan PH, Bridwell-Rabb J. A structure-function analysis of chlorophyllase reveals a mechanism for activity regulation dependent on disulfide bonds. J Biol Chem 2023; 299:102958. [PMID: 36731794 PMCID: PMC10011514 DOI: 10.1016/j.jbc.2023.102958] [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: 12/21/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 02/01/2023] Open
Abstract
Chlorophyll pigments are used by photosynthetic organisms to facilitate light capture and mediate the conversion of sunlight into chemical energy. Due to the indispensable nature of this pigment and its propensity to form reactive oxygen species, organisms heavily invest in its biosynthesis, recycling, and degradation. One key enzyme implicated in these processes is chlorophyllase, an α/β hydrolase that hydrolyzes the phytol tail of chlorophyll pigments to produce chlorophyllide molecules. This enzyme was discovered a century ago, but despite its importance to diverse photosynthetic organisms, there are still many missing biochemical details regarding how chlorophyllase functions. Here, we present the 4.46-Å resolution crystal structure of chlorophyllase from Triticum aestivum. This structure reveals the dimeric architecture of chlorophyllase, the arrangement of catalytic residues, an unexpected divalent metal ion-binding site, and a substrate-binding site that can accommodate a diverse range of pigments. Further, this structure exhibits the existence of both intermolecular and intramolecular disulfide bonds. We investigated the importance of these architectural features using enzyme kinetics, mass spectrometry, and thermal shift assays. Through this work, we demonstrated that the oxidation state of the Cys residues is imperative to the activity and stability of chlorophyllase, illuminating a biochemical trigger for responding to environmental stress. Additional bioinformatics analysis of the chlorophyllase enzyme family reveals widespread conservation of key catalytic residues and the identified "redox switch" among other plant chlorophyllase homologs, thus revealing key details regarding the structure-function relationships in chlorophyllase.
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Affiliation(s)
- Minshik Jo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Madison Knapp
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - David G Boggs
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Marley Brimberry
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Patrick H Donnan
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
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Li D, Yu F, Zhang Y, Hu K, Dai D, Song S, Zhang F, Sa R, Lian H, Sheng Y. Integrative analysis of different low-light-tolerant cucumber lines in response to low-light stress. FRONTIERS IN PLANT SCIENCE 2023; 13:1093859. [PMID: 36743563 PMCID: PMC9891299 DOI: 10.3389/fpls.2022.1093859] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/14/2022] [Indexed: 06/18/2023]
Abstract
INTRODUCTION Low light stress inhibits plant growth due to a line of physiological disruptions in plants, and is one of the major barriers to protected cucumber cultivation in northern China. METHODS To comprehensively understand the responses of cucumber seedlings to low-light stress, the low-light-tolerant line (M67) and The low-light-sensitive line (M14) were conducted for the analysis of photosynthetic phenotype, RNA sequencing (RNA-seq) and the expression level of photosynthesis-related genes in leaves under low-light stress and normal light condition (control). RESULTS The results showed that there was a sharp decrease in the photosynthate accumulation in the leaves of the sensitive line, M14, resulting in a large decrease in the photosynthetic rate (Pn) (with 31.99%) of leaves compared to that of the control, which may have been caused by damage to chloroplast ultrastructure or a decrease in chlorophyll (Chl) content. However, under the same low-light treatment, there was no large drop in the photosynthate accumulation and even no decrease in Pn and Chl content for the tolerant line, M67. Moreover, results of gene expression analysis showed that the expression level of genes CsPsbQ (the photosystem II oxygen-evolving enhancer protein 3 gene) and Csgamma (ATPase, F1 complex gene) in the M14 leaves decreased sharply (by 35.04% and 30.58%, respectively) compared with the levels in the M67 leaves, which decreased by 14.78% and 23.61%, respectively. The expression levels of genes involved in Chl synthesis and carbohydrate biosynthesis in the leaves of M14 decreased markedly after low-light treatment; in contrast, there were no sharp decreases or changes in leaves of M67. DISCUSSION Over all, the ability of cucumber to respond to low-light stress, as determined on the basis of the degree of damage in leaf structure and chloroplast ultrastructure, which corresponded to decreased gene expression levels and ATP phosphorylase activity, significantly differed between different low-light-tolerant lines, which was manifested as significant differences in photosynthetic capacity between them. Results of this study will be a reference for comprehensive insight into the physiological mechanism involved in the low-light tolerance of cucumber.
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Affiliation(s)
- Dandan Li
- *Correspondence: Dandan Li, ; Yunyan Sheng,
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Karg CA, Parráková L, Fuchs D, Schennach H, Kräutler B, Moser S, Gostner JM. A Chlorophyll-Derived Phylloxanthobilin Is a Potent Antioxidant That Modulates Immunometabolism in Human PBMC. Antioxidants (Basel) 2022; 11:antiox11102056. [PMID: 36290779 PMCID: PMC9599000 DOI: 10.3390/antiox11102056] [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: 09/12/2022] [Revised: 09/30/2022] [Accepted: 10/07/2022] [Indexed: 11/16/2022] Open
Abstract
Phyllobilins are natural products derived from the degradation of chlorophyll, which proceeds via a common and strictly controlled pathway in higher plants. The resulting tetrapyrrolic catabolites—the phyllobilins—are ubiquitous in nature; despite their high abundance, there is still a lack of knowledge about their physiological properties. Phyllobilins are part of human nutrition and were shown to be potent antioxidants accounting with interesting physiological properties. Three different naturally occurring types of phyllobilins—a phylloleucobilin, a dioxobilin-type phylloleucobilin and a phylloxanthobilin (PxB)—were compared regarding potential antioxidative properties in a cell-free and in a cell-based antioxidant activity test system, demonstrating the strongest effect for the PxB. Moreover, the PxB was investigated for its capacity to interfere with immunoregulatory metabolic pathways of tryptophan breakdown in human blood peripheral mononuclear cells. A dose-dependent inhibition of tryptophan catabolism to kynurenine was observed, suggesting a suppressive effect on pathways of cellular immune activation. Although the exact mechanisms of immunomodulatory effects are yet unknown, these prominent bioactivities point towards health-relevant effects, which warrant further mechanistic investigations and the assessment of the in vivo extrapolatability of results. Thus, phyllobilins are a still surprisingly unexplored family of natural products that merit further investigation.
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Affiliation(s)
- Cornelia A. Karg
- Department of Pharmaceutical Biology, Ludwig-Maximilian University of Munich, Butenandtstr. 5–13, 81977 Munich, Germany
| | - Lucia Parráková
- Institute of Medical Biochemistry, Medical University of Innsbruck, Innrain 80, 6020 Innsbruck, Austria
| | - Dietmar Fuchs
- Institute of Biological Chemistry, Medical University of Innsbruck, Innrain 80, 6020 Innsbruck, Austria
| | - Harald Schennach
- Central Institute of Blood Transfusion and Immunology, University Hospital, Anichstr. 35, 6020 Innsbruck, Austria
| | - Bernhard Kräutler
- Institute of Organic Chemistry, Center for Molecular Biosciences, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Simone Moser
- Department of Pharmaceutical Biology, Ludwig-Maximilian University of Munich, Butenandtstr. 5–13, 81977 Munich, Germany
- Correspondence: (S.M.); (J.M.G.); Tel.: +49-89-2180-77175 (S.M.); +43-512-9003-70120 (J.M.G.)
| | - Johanna M. Gostner
- Institute of Medical Biochemistry, Medical University of Innsbruck, Innrain 80, 6020 Innsbruck, Austria
- Correspondence: (S.M.); (J.M.G.); Tel.: +49-89-2180-77175 (S.M.); +43-512-9003-70120 (J.M.G.)
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Koli P. Characterization, stability, and feasibility of long-term use of light-absorbing components of aqueous spinach extract-based photogalvanic electrolyte. Sci Rep 2022; 12:13518. [PMID: 35934715 PMCID: PMC9357696 DOI: 10.1038/s41598-022-17647-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 07/28/2022] [Indexed: 11/09/2022] Open
Abstract
In the present work, the photogalvanic cells have been studied with respect to the photo-stability and the long-term use of the electrolyte based on crude aqueous spinach extract sensitizer for solar energy harvesting. Further, the nature of chemical components present in the old and photo-decayed electrolyte and their current generation capacity has also not been investigated so far otherwise it is of much significance for durable use of the same electrolyte in cells. In earlier studies, the steady-state photo-generation of current for about two hours from crude spinach extract-based cell has been shown during illumination. But, the data for only two hours of the steady-state current generation is not sufficient to show the feasibility of working with photogalvanic cells. Therefore, to fill this research gap of lack of characterization of sensitizers' molecules of crude spinach extract and lack of study on long-term use of this electrolyte (crude spinach extract-surfactant-reductant-alkali-water), the present extensive study has been done. The observed spectrum of crude spinach extract resembles that of chlorophyll-protein complex showing it is the main chemical component in extract absorbing light. A strong acid adversely affects the extract's photogalvanics and high pH is friendly to the physiological and photogalvanic activity of the extract. The spectra of illuminated and very old crude spinach extract-NaOH-Sodium lauryl sulfate (NaLS)-Fructose photogalvanic electrolyte solution show negligible absorbance (540-700 nm) and zero absorbance (at 700 nm) suggesting the absence of chlorophyll due to its photo-degradation. When this photo-degraded electrolyte is again illuminated, the power output obtained is nearly equal to that for the first time illuminated fresh electrolyte. The observed current at zero time and after 2641 h from the same electrolyte used in long term is 50 mA cm-2 and 40 mA cm-2, respectively. It means that the fresh crude spinach extract, as well as the photo-degraded extract at high pH, are almost equally capable of power generation.
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Affiliation(s)
- Pooran Koli
- Department of Chemistry, Jai Narain Vyas University, Jodhpur, Rajasthan, 342033, India.
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8
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Woodson JD. Control of chloroplast degradation and cell death in response to stress. Trends Biochem Sci 2022; 47:851-864. [DOI: 10.1016/j.tibs.2022.03.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/25/2022] [Accepted: 03/14/2022] [Indexed: 12/16/2022]
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Schumacher I, Menghini D, Ovinnikov S, Hauenstein M, Fankhauser N, Zipfel C, Hörtensteiner S, Aubry S. Evolution of chlorophyll degradation is associated with plant transition to land. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1473-1488. [PMID: 34931727 PMCID: PMC9306834 DOI: 10.1111/tpj.15645] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/09/2021] [Accepted: 12/15/2021] [Indexed: 05/27/2023]
Abstract
Chlorophyll, the central pigment of photosynthesis, is highly photo‐active and degraded enzymatically during leaf senescence. Merging comparative genomics and metabolomics, we evaluate the extent to which the chlorophyll detoxification pathway has evolved in Viridiplantae. We argue that cytosolic detoxification of phyllobilins in particular was a critical process to the green lineage’s transition to land.
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Affiliation(s)
- Isabel Schumacher
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Damian Menghini
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Serguei Ovinnikov
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Mareike Hauenstein
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Niklaus Fankhauser
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Cyril Zipfel
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Stefan Hörtensteiner
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
| | - Sylvain Aubry
- Department of Plant and Microbial BiologyUniversity of ZürichZürich8008Switzerland
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Facile retro-Dieckmann cleavage of a pink phyllobilin: new type of potential downstream steps of natural chlorophyll breakdown. MONATSHEFTE FUR CHEMIE 2022. [DOI: 10.1007/s00706-022-02894-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractIn senescent leaves of higher plants, colourless chlorophyll (Chl) catabolites typically accumulate temporarily, and undergo natural oxidation, in part, to yellow- and pink-coloured phyllobilins (PBs). The latter, also classified as phylloroseobilins (PrBs), represent the final currently established products of Chl-breakdown, possibly playing important roles in metabolism. However, PrBs, themselves, do not accumulate in the leaves. Indeed, the original PrB identified, then classified as a pink Chl-catabolite (PiCC), is remarkably instable in methanolic solution. As reported here, PiCC readily converts at room temperature into yellow tetrapyrroles. The deduced main process, a retro-Dieckmann reaction, cleaves open its ring E moiety, the α-methoxycarbonyl-cyclopentanone unit characteristic of the Chls and of the natural Chl-derived PBs. This readily occurring reaction of the PiCC represents an unprecedented skeletal transformation of a PB, furnishing a cross-conjugated biladiene with a basic structure more similar to the heme-derived bilins.
Graphical abstract
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Zentgraf U, Andrade-Galan AG, Bieker S. Specificity of H 2O 2 signaling in leaf senescence: is the ratio of H 2O 2 contents in different cellular compartments sensed in Arabidopsis plants? Cell Mol Biol Lett 2022; 27:4. [PMID: 34991444 PMCID: PMC8903538 DOI: 10.1186/s11658-021-00300-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/17/2021] [Indexed: 01/21/2023] Open
Abstract
Leaf senescence is an integral part of plant development and is driven by endogenous cues such as leaf or plant age. Developmental senescence aims to maximize the usage of carbon, nitrogen and mineral resources for growth and/or for the sake of the next generation. This requires efficient reallocation of the resources out of the senescing tissue into developing parts of the plant such as new leaves, fruits and seeds. However, premature senescence can be induced by severe and long-lasting biotic or abiotic stress conditions. It serves as an exit strategy to guarantee offspring in an unfavorable environment but is often combined with a trade-off in seed number and quality. In order to coordinate the very complex process of developmental senescence with environmental signals, highly organized networks and regulatory cues have to be in place. Reactive oxygen species, especially hydrogen peroxide (H2O2), are involved in senescence as well as in stress signaling. Here, we want to summarize the role of H2O2 as a signaling molecule in leaf senescence and shed more light on how specificity in signaling might be achieved. Altered hydrogen peroxide contents in specific compartments revealed a differential impact of H2O2 produced in different compartments. Arabidopsis lines with lower H2O2 levels in chloroplasts and cytoplasm point to the possibility that not the actual contents but the ratio between the two different compartments is sensed by the plant cells.
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Affiliation(s)
- Ulrike Zentgraf
- ZMBP (Centre of Plant Molecular Biology), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany.
| | - Ana Gabriela Andrade-Galan
- ZMBP (Centre of Plant Molecular Biology), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
| | - Stefan Bieker
- ZMBP (Centre of Plant Molecular Biology), University of Tübingen, Auf der Morgenstelle 32, 72076, Tübingen, Germany
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Research Progress in the Interconversion, Turnover and Degradation of Chlorophyll. Cells 2021; 10:cells10113134. [PMID: 34831365 PMCID: PMC8621299 DOI: 10.3390/cells10113134] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 01/01/2023] Open
Abstract
Chlorophylls (Chls, Chl a and Chl b) are tetrapyrrole molecules essential for photosynthetic light harvesting and energy transduction in plants. Once formed, Chls are noncovalently bound to photosynthetic proteins on the thylakoid membrane. In contrast, they are dismantled from photosystems in response to environmental changes or developmental processes; thus, they undergo interconversion, turnover, and degradation. In the last twenty years, fruitful research progress has been achieved on these Chl metabolic processes. The discovery of new metabolic pathways has been accompanied by the identification of enzymes associated with biochemical steps. This article reviews recent progress in the analysis of the Chl cycle, turnover and degradation pathways and the involved enzymes. In addition, open questions regarding these pathways that require further investigation are also suggested.
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Karg CA, Wang S, Al Danaf N, Pemberton RP, Bernard D, Kretschmer M, Schneider S, Zisis T, Vollmar AM, Lamb DC, Zahler S, Moser S. Tetrapyrrolische Pigmente aus dem Häm‐ und Chlorophyllabbau interagieren mit Aktin. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Cornelia A. Karg
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Shuaijun Wang
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Nader Al Danaf
- Center for Nanoscience (CeNS) und Nanosystems Initiative Munich (NIM) Department Chemie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Ryan P. Pemberton
- Atomwise Inc. 717 Market Street, Suite 800 San Francisco CA 94103 USA
| | - Denzil Bernard
- Atomwise Inc. 717 Market Street, Suite 800 San Francisco CA 94103 USA
| | - Maibritt Kretschmer
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Sabine Schneider
- Department Chemie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Themistoklis Zisis
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Angelika M. Vollmar
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Don C. Lamb
- Center for Nanoscience (CeNS) und Nanosystems Initiative Munich (NIM) Department Chemie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Stefan Zahler
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
| | - Simone Moser
- Pharmazeutische Biologie Department Pharmazie Ludwig-Maximilians-Universität München Butenandtstraße 5–13 81377 München Deutschland
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Karg CA, Wang S, Al Danaf N, Pemberton RP, Bernard D, Kretschmer M, Schneider S, Zisis T, Vollmar AM, Lamb DC, Zahler S, Moser S. Tetrapyrrolic Pigments from Heme- and Chlorophyll Breakdown are Actin-Targeting Compounds. Angew Chem Int Ed Engl 2021; 60:22578-22584. [PMID: 34310831 PMCID: PMC8519017 DOI: 10.1002/anie.202107813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/22/2021] [Indexed: 11/11/2022]
Abstract
Chlorophyll and heme are among the "pigments of life", tetrapyrrolic structures, without which life on Earth would not be possible. Their catabolites, the phyllobilins and the bilins, respectively, share not only structural features, but also a similar story: Long considered waste products of detoxification processes, important bioactivities for both classes have now been demonstrated. For phyllobilins, however, research on physiological roles is sparse. Here, we introduce actin, the major component of the cytoskeleton, as the first discovered target of phyllobilins and as a novel target of bilins. We demonstrate the inhibition of actin dynamics in vitro and effects on actin and related processes in cancer cells. A direct interaction with G-actin is shown by in silico studies and confirmed by affinity chromatography. Our findings open a new chapter in bioactivities of tetrapyrroles-especially phyllobilins-for which they form the basis for broad implications in plant science, ecology, and physiology.
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Affiliation(s)
- Cornelia A. Karg
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Shuaijun Wang
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Nader Al Danaf
- Center for Nanoscience (CeNS) and Nanosystems Initiative Munich (NIM)Department of ChemistryLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | | | - Denzil Bernard
- Atomwise Inc.717 Market Street, Suite 800San FranciscoCA94103USA
| | - Maibritt Kretschmer
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Sabine Schneider
- Department of ChemistryLudwig-Maximilians University MunichButenandtstrasse 5–1381377MunichGermany
| | - Themistoklis Zisis
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Angelika M. Vollmar
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Don C. Lamb
- Center for Nanoscience (CeNS) and Nanosystems Initiative Munich (NIM)Department of ChemistryLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Stefan Zahler
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Simone Moser
- Pharmaceutical BiologyDepartment of PharmacyLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
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15
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Domínguez F, Cejudo FJ. Chloroplast dismantling in leaf senescence. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5905-5918. [PMID: 33959761 PMCID: PMC8760853 DOI: 10.1093/jxb/erab200] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/03/2021] [Indexed: 05/02/2023]
Abstract
In photosynthetic plant cells, chloroplasts act as factories of metabolic intermediates that support plant growth. Chloroplast performance is highly influenced by environmental cues. Thus, these organelles have the additional function of sensing ever changing environmental conditions, thereby playing a key role in harmonizing the growth and development of different organs and in plant acclimation to the environment. Moreover, chloroplasts constitute an excellent source of metabolic intermediates that are remobilized to sink tissues during senescence so that chloroplast dismantling is a tightly regulated process that plays a key role in plant development. Stressful environmental conditions enhance the generation of reactive oxygen species (ROS) by chloroplasts, which may lead to oxidative stress causing damage to the organelle. These environmental conditions trigger mechanisms that allow the rapid dismantling of damaged chloroplasts, which is crucial to avoid deleterious effects of toxic by-products of the degradative process. In this review, we discuss the effect of redox homeostasis and ROS generation in the process of chloroplast dismantling. Furthermore, we summarize the structural and biochemical events, both intra- and extraplastid, that characterize the process of chloroplast dismantling in senescence and in response to environmental stresses.
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Affiliation(s)
- Fernando Domínguez
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla and Consejo Superior de Investigaciones Científicas, Avda. Américo Vespucio 49, 41092-Sevilla, Spain
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16
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Aubry S, Christ B, Kräutler B, Martinoia E, Thomas H, Zipfel C. An evergreen mind and a heart for the colors of fall. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4625-4633. [PMID: 33860301 PMCID: PMC8219035 DOI: 10.1093/jxb/erab162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 04/11/2021] [Indexed: 06/01/2023]
Abstract
With the finest biochemical and molecular approaches, convincing explorative strategies, and long-term vision, Stefan Hörtensteiner succeeded in elucidating the biochemical pathway responsible for chlorophyll degradation. After having contributed to the identification of key chlorophyll degradation products in the course of the past 25 years, he gradually identified and characterized most of the crucial players in the PAO/phyllobilin degradation pathway of chlorophyll. He was one of the brightest plant biochemists of his generation, and his work opened doors to a better understanding of plant senescence, tetrapyrrole homeostasis, and their complex regulation. He sadly passed away on 5 December 2020, aged 57.
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Affiliation(s)
- Sylvain Aubry
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Bastien Christ
- Berries and Medicinal Plants, Plant Production Systems, Agroscope, Conthey, Switzerland
| | - Bernhard Kräutler
- Institute of Organic Chemistry & Center of Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - Enrico Martinoia
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
| | - Howard Thomas
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth, Wales, UK
| | - Cyril Zipfel
- Department of Plant and Microbial Biology, University of Zürich, Zürich, Switzerland
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17
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Li C, Podewitz M, Kräutler B. A Blue Zinc Complex of a Dioxobilin‐Type Pink Chlorophyll Catabolite Exhibiting Bright Chelation‐Enhanced Red Fluorescence. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100206] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry University of Innsbruck Innrain 80/82 6020 Innsbruck Austria
- Center of Molecular Biosciences University of Innsbruck (CMBI) Innrain 80/82 6020 Innsbruck Austria
- Present address: Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry & Molecular Engineering East China University of Science & Technology Meilong Rd 130 200237 Shanghai China
| | - Maren Podewitz
- Center of Molecular Biosciences University of Innsbruck (CMBI) Innrain 80/82 6020 Innsbruck Austria
- Institute of General Inorganic and Theoretical Chemistry University of Innsbruck Innrain 80/82 6020 Innsbruck Austria
| | - Bernhard Kräutler
- Institute of Organic Chemistry University of Innsbruck Innrain 80/82 6020 Innsbruck Austria
- Center of Molecular Biosciences University of Innsbruck (CMBI) Innrain 80/82 6020 Innsbruck Austria
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18
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Karg CA, Doppler C, Schilling C, Jakobs F, Dal Colle MCS, Frey N, Bernhard D, Vollmar AM, Moser S. A yellow chlorophyll catabolite in leaves of Urtica dioica L.: An overlooked phytochemical that contributes to health benefits of stinging nettle. Food Chem 2021; 359:129906. [PMID: 33962192 DOI: 10.1016/j.foodchem.2021.129906] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 03/19/2021] [Accepted: 04/16/2021] [Indexed: 10/21/2022]
Abstract
Stinging nettle is appreciated for its antioxidant and anti-inflammatory properties, which renders the plant a popular ingredient in a healthy diet in form of salads or smoothies. The most common use, presumably, is of dried leaves as ingredient in tea mixtures. The plant's health benefits are attributed primarily to phenolic phytochemicals. Here we describe the characterization and quantification of a phylloxanthobilin (PxB), a yellow chlorophyll catabolite, in nettle tea. Despite their abundance in the plant kingdom, chlorophyll catabolites have been overlooked as phytochemicals and as part of human nutrition. Our investigations of tea reveal that one cup of nettle tea contains about 50 µg of PxB with large variations depending on the supplier. When investigating the bioactivities of PxB, our observations show that PxB has antioxidative and anti-inflammatory activities comparable to known bioactive small molecules found in nettle, indicating the phylloxanthobilin to be an overlooked ingredient of nettle tea.
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Affiliation(s)
- Cornelia A Karg
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany
| | - Christian Doppler
- Division of Pathophysiology, Institute of Physiology and Pathophysiology, Medical Faculty, Johannes-Kepler-University Linz, Krankenhausstrasse 7a, A-4020 Linz, Austria
| | - Charlotte Schilling
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany
| | - Franziska Jakobs
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany; Department of Chemistry, High Point University, One University Parkway High Point, NC 27268, United States
| | - Marlene C S Dal Colle
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany; Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Nadine Frey
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany
| | - David Bernhard
- Division of Pathophysiology, Institute of Physiology and Pathophysiology, Medical Faculty, Johannes-Kepler-University Linz, Krankenhausstrasse 7a, A-4020 Linz, Austria
| | - Angelika M Vollmar
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany
| | - Simone Moser
- Department of Pharmacy, Center for Drug Research, Pharmaceutical Biology, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, D-81377 München, Germany.
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19
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Oetama VSP, Pentzold S, Boland W. The fate of chlorophyll in phytophagous insects goes beyond nutrition. Z NATURFORSCH C 2021; 76:1-9. [PMID: 32887212 DOI: 10.1515/znc-2020-0060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Chlorophyll (Chl) is a natural compound that is found in all autotrophic plants. Since phytophagous insects ingest the photosynthetically active material with the plant leaves, the question arises if and how herbivores deal with Chl and its degradation products. Here we review findings on Chl degradation in phytophagous insects and highlight the role of these ubiquitous plant metabolites for plant-feeding insects. Due to the anaerobic gut of many insects, the degradation is limited to the removal of the peripheral substituents, while the tetrapyrrole core remains intact. Proteins, such as red fluorescent protein, P252 (a novel 252-kDa protein), and chlorophyllide binding protein have been reported to occur in the insect gut and might be indirectly connected to Chl degradation. Besides of an nutritional value, e.g., by taking up Mg2+ ions or by sequestration of carbon from the phytol side chain, the Chl degradation products may serve the insect, after binding to certain proteins, as antimicrobial, antifungal, and antiviral factors. The protein complexes may also confer protection against reactive oxygen species. The antibiotic potential of proteins and degradation products does not only benefit phytophagous insects but also human being in medical application of cancer treatment for instance. This review highlights these aspects from a molecular, biochemical, and ecological point of view.
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Affiliation(s)
- Vincensius S P Oetama
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knvll-Stra_e 8, 07745 Jena, Germany
| | - Stefan Pentzold
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knvll-Stra_e 8, 07745 Jena, Germany.,Friedrich Schiller University Jena, University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - Wilhelm Boland
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knvll-Stra_e 8, 07745 Jena, Germany
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20
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Ritter M, Oetama VSP, Schulze D, Muetzlaff K, Meents AK, Seidel RA, Görls H, Westerhausen M, Boland W, Pohnert G. Pyrrolic and Dipyrrolic Chlorophyll Degradation Products in Plants and Herbivores. Chemistry 2020; 26:6205-6213. [PMID: 31971638 PMCID: PMC7318184 DOI: 10.1002/chem.201905236] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/21/2020] [Indexed: 12/21/2022]
Abstract
The degradation of chlorophyll, the omnipresent green pigment, has been investigated intensively over the last 30 years resulting in many elucidated tetrapyrrolic degradation products. With a comparison to the degradation of the structurally similar heme, we hereby propose a novel additional chlorophyll degradation mechanism to mono- and dipyrrolic products. This is the first proof of the occurrence of a family of mono- and dipyrrols in leaves that are previously only known as heme degradation products. This product family is also found in spit and feces of herbivores with specific metabolomic patterns reflecting the origin of the samples. Based on chromatographic and mass spectrometric evidence as well as on mechanistic considerations we also suggest several tentative new degradation products. One of them, dihydro BOX A, was fully confirmed as a novel natural product by synthesis and comparison of its spectroscopic data.
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Affiliation(s)
- Marcel Ritter
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryLessingstr. 807743JenaGermany
| | | | - Daniel Schulze
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryHumboldtstr. 807743JenaGermany
| | - Katrin Muetzlaff
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryLessingstr. 807743JenaGermany
| | - Anja K. Meents
- Max Planck Institute for Chemical EcologyHans-Knöll-Str. 807745JenaGermany
| | - Raphael A. Seidel
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryLessingstr. 807743JenaGermany
| | - Helmar Görls
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryHumboldtstr. 807743JenaGermany
| | - Matthias Westerhausen
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryHumboldtstr. 807743JenaGermany
| | - Wilhelm Boland
- Max Planck Institute for Chemical EcologyHans-Knöll-Str. 807745JenaGermany
| | - Georg Pohnert
- Friedrich Schiller University JenaInstitute of Inorganic and Analytical ChemistryLessingstr. 807743JenaGermany
- Max Planck Institute for Chemical EcologyHans-Knöll-Str. 807745JenaGermany
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21
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Monitoring of Canopy Stress Symptoms in New Zealand Kauri Trees Analysed with AISA Hyperspectral Data. REMOTE SENSING 2020. [DOI: 10.3390/rs12060926] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The endemic New Zealand kauri trees (Agathis australis) are under threat by the deadly kauri dieback disease (Phytophthora agathidicida (PA)). This study aimed to identify spectral index combinations for characterising visible stress symptoms in the kauri canopy. The analysis is based on an aerial AISA hyperspectral image mosaic and 1258 reference crowns in three study sites in the Waitakere Ranges west of Auckland. A field-based assessment scheme for canopy stress symptoms (classes 1–5) was further optimised for use with RGB aerial images. A combination of four indices with six bands in the spectral range 450–1205 nm resulted in a correlation of 0.93 (mean absolute error 0.27, RMSE 0.48) for all crown sizes. Comparable results were achieved with five indices in the 450–970 nm region. A Random Forest (RF) regression gave the most accurate predictions while a M5P regression tree performed nearly as well and a linear regression resulted in slightly lower correlations. Normalised Difference Vegetation Indices (NDVI) in the near-infrared / red spectral range were the most important index combinations, followed by indices with bands in the near-infrared spectral range from 800 to 1205 nm. A test on different crown sizes revealed that stress symptoms in smaller crowns with denser foliage are best described in combination with pigment-sensitive indices that include bands in the green and blue spectral range. A stratified approach with individual models for pre-segmented low and high forest stands improved the overall performance. The regression models were also tested in a pixel-based analysis. A manual interpretation of the resulting raster map with stress symptom patterns observed in aerial imagery indicated a good match. With bandwidths of 10 nm and a maximum number of six bands, the selected index combinations can be used for large-area monitoring on an airborne multispectral sensor. This study establishes the base for a cost-efficient, objective monitoring method for stress symptoms in kauri canopies, suitable to cover large forest areas with an airborne multispectral sensor.
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Silva JB, Maciel-Silva AS, Santos NDD. The response of the moss Campylopus lamellatus (Leucobryaceae Schimp.) post El Niño: a case study in the Caatinga. RODRIGUÉSIA 2020. [DOI: 10.1590/2175-7860202071129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract Biological soil crusts (biocrusts) are important biological components in arid and semi-arid regions because they can serve as ecological facilitators for the vascular flora. Biocrusts of rocky outcrops of the Caatinga biome in the semiarid region of Northeast Brazil are comprised mainly of populations of the pioneer moss Campylopus lamellatus. Meanwhile, the Caatinga is undergoing progressive desertification, which is likely to continue for the next 100 years. Therefore, the physiological responses of C. lamellatus to climate change should be included in predictions regarding the future of the flora of these rocky environments. We evaluated a population of C. lamellatus during a prolonged drought brought about by El Niño, and during the first subsequent rainy season. We used biomass (dry mass) and proportion of chlorophyll as measures of tolerance. We identified decreased investment in biomass allocation and the degradation of photosynthetic pigments during the drought event. In contrast, we observed a rapid increase of chlorophyll during the rainy season, which represents biomass investment via chlorophyll regeneration. We conclude that the resilience of C. lamellatus is rapid, even for a photophilic plant, and should ensure its facilitative function under conditions of water saturation of the environment.
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23
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Perea R, Fernandes GW, Dirzo R. Early plant development depends on embryo damage location: the role of seed size in partial seed predation. OIKOS 2019. [DOI: 10.1111/oik.06912] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Ramón Perea
- Dept of Biology, Stanford Univ. 371 Serra Mall Stanford CA 94305 USA
- Depto de Sistemas y Recursos Naturales, Univ. Politécnica de Madrid Madrid Spain
| | - G. Wilson Fernandes
- Dept of Biology, Stanford Univ. 371 Serra Mall Stanford CA 94305 USA
- Depto de Biologia Geral, Univ. Federal de Minas Gerais Belo Horizonte MG Brazil
| | - Rodolfo Dirzo
- Dept of Biology, Stanford Univ. 371 Serra Mall Stanford CA 94305 USA
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24
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Karg CA, Wang P, Vollmar AM, Moser S. Re-opening the stage for Echinacea research - Characterization of phylloxanthobilins as a novel anti-oxidative compound class in Echinacea purpurea. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 60:152969. [PMID: 31153733 DOI: 10.1016/j.phymed.2019.152969] [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: 03/31/2019] [Revised: 05/19/2019] [Accepted: 05/22/2019] [Indexed: 05/07/2023]
Abstract
BACKGROUND Phylloxanthobilins are tetrapyrrolic natural products that arise from the degradation of chlorophyll. Phylloxanthobilins have been discovered roughly 10 years ago in the leaves of deciduous trees, and are now considered a compound class with high and still unexplored potential of bioactivities. To date, however, there are no reports on the occurrence of phylloxanthobilins in parts of a medicinal plant used for pharmaceutical preparations. PURPOSE The relevance of Echinacea purpurea as medicinal plant is undoubtedly high, and a large variety of pharmaceutical preparations is available on the market, mostly for the treatment of the common cold. Nevertheless, its phytochemical profiling has been limited to analysis for previously characterized substances, and this has not explained all its pharmacological efficacies. We therefore set out to investigate the occurrence of phylloxanthobilins in Echinacea purpurea. METHODS Phylloxanthobilins in leaf extracts of Echinacea purpurea were detected using analytical HPLC. Identified phyllobilins were purified from plant material and characterized by UV/Vis, mass spectrometry, MS/MS, and confirmed by co-injections with previously published phyllobilins from different sources. The anti-oxidant activity of selected isolated phylloxanthobilins was assessed by an in vitro ferric reducing antioxidant power (FRAP) assay; in addition, the ability to scavenge ROS in cells caused by hydrogen peroxide stimulation was determined by measuring H2DCF-DA fluorescence and by assessing cellular GSH levels. RESULTS In extracts of Echinacea purpurea leaves, an unprecedented diversity of phylloxanthobilins was detected; surprisingly, not only in senescent yellow leaves, but also in green leaves with no visible chlorophyll degradation. Six phylloxanthobilins were identified and structurally characterized. The uptake of phylloxanthobilins by human endothelial kidney cells was demonstrated. When investigating the anti-oxidative activity of these natural products, a potent in vitro activity was demonstrated; in addition, phylloxanthobilins possess intracellular ROS scavenging ability and can prevent oxidative stress as assessed by total cellular GSH levels. CONCLUSION Phylloxanthobilins are important constituents of Echinacea purpurea extracts, and our first exploratory studies hint towards promising bioactivities of these natural products, which may be relevant for understanding Echinacea efficacies.
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Affiliation(s)
- Cornelia A Karg
- Pharmaceutical Biology, Department Pharmacy, Ludwig-Maximilians University of Munich, Butenandtstraße 5-13, Munich 81377, Germany
| | - Pengyu Wang
- Pharmaceutical Biology, Department Pharmacy, Ludwig-Maximilians University of Munich, Butenandtstraße 5-13, Munich 81377, Germany
| | - Angelika M Vollmar
- Pharmaceutical Biology, Department Pharmacy, Ludwig-Maximilians University of Munich, Butenandtstraße 5-13, Munich 81377, Germany
| | - Simone Moser
- Pharmaceutical Biology, Department Pharmacy, Ludwig-Maximilians University of Munich, Butenandtstraße 5-13, Munich 81377, Germany.
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25
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Moser S, Kräutler B. In Search of Bioactivity - Phyllobilins, an Unexplored Class of Abundant Heterocyclic Plant Metabolites from Breakdown of Chlorophyll. Isr J Chem 2019; 59:420-431. [PMID: 31244492 PMCID: PMC6582504 DOI: 10.1002/ijch.201900012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/30/2019] [Accepted: 03/31/2019] [Indexed: 12/04/2022]
Abstract
The fate of the green plant pigment chlorophyll (Chl) in de-greening leaves has long been a fascinating biological puzzle. In the course of the last three decades, various bilin-type products of Chl breakdown have been identified, named phyllobilins (PBs). Considered 'mere' leftovers of a controlled biological Chl detoxification originally, the quest for finding relevant bioactivities of the PBs has become a new paradigm. Indeed, the PBs are abundant in senescent leaves, in ripe fruit and in some vegetables, and they display an exciting array of diverse heterocyclic structures. This review outlines briefly which types of Chl breakdown products occur in higher plants, describes basics of their bio-relevant structural and chemical properties and gives suggestions as to 'why' the plants produce vast amounts of uniquely 'decorated' heterocyclic compounds. Clearly, it is worthwhile to consider crucial metabolic roles of PBs in plants, which may have practical consequences in agriculture and horticulture. However, PBs are also part of our plant-based nutrition and their physiological and pharmacological effects in humans are of interest, as well.
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Affiliation(s)
- Simone Moser
- Pharmaceutical Biology, Pharmacy DepartmentLudwig-Maximilians University of MunichButenandtstraße 5–1381377MunichGermany
| | - Bernhard Kräutler
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of Innsbruck. Innrain 80/826020InnsbruckAustria
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Li C, Kräutler B. A pink colored dioxobilin-type phyllobilin from breakdown of chlorophyll. MONATSHEFTE FUR CHEMIE 2019. [DOI: 10.1007/s00706-019-02396-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Li C, Erhart T, Liu X, Kräutler B. Yellow Dioxobilin-Type Tetrapyrroles from Chlorophyll Breakdown in Higher Plants-A New Class of Colored Phyllobilins. Chemistry 2019; 25:4052-4057. [PMID: 30688378 PMCID: PMC6563717 DOI: 10.1002/chem.201806038] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Indexed: 11/11/2022]
Abstract
In senescent leaves chlorophyll (Chl) catabolites typically accumulate as colorless tetrapyrroles, classified as formyloxobilin-type (or type-I) or dioxobilin-type (type-II) phyllobilins (PBs). Yellow type-I Chl catabolites (YCCs) also occur in some senescent leaves, in which they are generated by oxidation of colorless type-I PBs. A yellow type-II PB was recently proposed to occur in extracts of fall leaves of grapevine (Vitis vinifera), tentatively identified by its mass and UV/Vis absorption characteristics. Here, the first synthesis of a yellow type-II Chl catabolite (DYCC) from its presumed natural colorless type-II precursor is reported. A homogenate of a Spatiphyllum wallisii leaf was used as "green" means of effective and selective oxidation. The synthetic DYCC was fully characterized and identified with the yellow grapevine leaf pigment. As related yellow type-I PBs do, the DYCC functions as a reversible photoswitch by undergoing selective photo-induced Z/E isomerization of its C15=C16 bond.
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Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry & Centre of, Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
- Present address: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular EngineeringEast China University of Science & TechnologyMeilong Rd 130200237ShanghaiChina
| | - Theresia Erhart
- Institute of Organic Chemistry & Centre of, Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Xiujun Liu
- Institute of Organic Chemistry & Centre of, Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
- Present address: Research Center of Analysis and TestEast China University of Science & TechnologyMeilong Rd 130200237ShanghaiChina
| | - Bernhard Kräutler
- Institute of Organic Chemistry & Centre of, Molecular Biosciences Innsbruck (CMBI)University of InnsbruckInnrain 80/826020InnsbruckAustria
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Abstract
Phytol, the prenyl side chain of chlorophyll, is derived from geranylgeraniol by reduction of three double bonds. Recent results demonstrated that the conversion of geranylgeraniol to phytol is linked to chlorophyll synthesis, which is catalyzed by protein complexes associated with the thylakoid membranes. One of these complexes contains light harvesting chlorophyll binding like proteins (LIL3), enzymes of chlorophyll synthesis (protoporphyrinogen oxidoreductase, POR; chlorophyll synthase, CHLG) and geranylgeranyl reductase (GGR). Phytol is not only employed for the synthesis of chlorophyll, but also for tocopherol (vitamin E), phylloquinol (vitamin K) and fatty acid phytyl ester production. Previously, it was believed that phytol is derived from reduction of geranylgeranyl-diphosphate originating from the 4-methylerythritol-5-phosphate (MEP) pathway. The identification and characterization of two kinases, VTE5 and VTE6, involved in phytol and phytyl-phosphate phosphorylation, respectively, indicated that most phytol employed for tocopherol synthesis is derived from reduction of geranylgeranylated chlorophyll to (phytol-) chlorophyll. After hydrolysis from chlorophyll, free phytol is phosphorylated by the two kinases, and phytyl-diphosphate employed for the synthesis of tocopherol and phylloquinol. The reason why some chloroplast lipids, i.e. chlorophyll, tocopherol and phylloquinol, are derived from phytol, while others, i.e. carotenoids and tocotrienols (in some plant species) are synthesized from geranylgeraniol, remains unclear.
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Carella F, Aceto S, Mangoni O, Mollica MP, Cavaliere G, Trinchese G, Aniello F, De Vico G. Assessment of the Health Status of Mussels Mytilus galloprovincialis Along the Campania Coastal Areas: A Multidisciplinary Approach. Front Physiol 2018; 9:683. [PMID: 29946265 PMCID: PMC6005891 DOI: 10.3389/fphys.2018.00683] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/16/2018] [Indexed: 01/21/2023] Open
Abstract
The bivalve Mytilus galloprovincialis has a broad geographic distribution, represent an important species for the ecology of coastal waters, also constituting a major aquaculture species. In the present work, molecular and tissue biomarkers were examined in mussel populations (M. galloprovincialis) located in four different areas of the coastal water of the Campania Region. During an annual life cycle, we analyzed the expression patterns of several genes commonly used to estimate cellular stress response and damage, namely p53, p63, HSP70, MT-10, and MT-20, related tissue lesions (pathogens, inflammations, digestive tubules damage), oxidative stress indicators (H2O2, SOD specific activity) and associated environmental data. The computed Principal Component Analysis showed that the areas were discernible based on the environmental data and biomarker results. About animal health status, mussels from Gulf of Pozzuoli and Naples's harbor did show a thinnest epithelial cell of digestive tubules compared to mussels sampled from other sampling sites; moreover, high prevalence of cases of intersex in three of the examinated areas were observed. The presence of a potential zoonotic pathogen (Nocardia crassostreae) was identified, appearing as an important possible emerging disease. We also reported the OIE notifiable protozoa Marteilia refringens in three areas out of four. The likely impact of both observed pathogens on the mussel health and shellfish aquaculture needs to be urgently addressed. Results are discussed considering animal histopathological health parameters and biological effects.
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Affiliation(s)
- Francesca Carella
- Department of Biology, University of Naples Federico II, Naples, Italy
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Wani ZA, Ahmad T, Nalli Y, Ali A, Singh AP, Vishwakarma RA, Ashraf N, Riyaz-Ul-Hassan S. Porostereum sp., Associated with Saffron (Crocus sativus L.), is a Latent Pathogen Capable of Producing Phytotoxic Chlorinated Aromatic Compounds. Curr Microbiol 2018; 75:880-887. [DOI: 10.1007/s00284-018-1461-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 02/19/2018] [Indexed: 11/24/2022]
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Lu S, Lu F, You W, Wang Z, Liu Y, Omasa K. A robust vegetation index for remotely assessing chlorophyll content of dorsiventral leaves across several species in different seasons. PLANT METHODS 2018; 14:15. [PMID: 29449875 PMCID: PMC5812224 DOI: 10.1186/s13007-018-0281-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 02/09/2018] [Indexed: 05/16/2023]
Abstract
BACKGROUND Leaf chlorophyll content (LCC) provides valuable information about plant physiology. Most of the published chlorophyll vegetation indices at the leaf level have been based on the spectral characteristics of the adaxial leaf surface, thus, they are not appropriate for estimating LCC when both the adaxial and abaxial leaf surfaces influence the spectral reflectance. We attempted to address this challenge by measuring the spectral reflectance of the adaxial and abaxial leaf surfaces of several plant species at different growth stages using a portable field spectroradiometer. The relationships between more than 30 published reflectance indices with LCC were analyzed to determine which index estimated LCC most effectively. Additionally, since the relationships determined on one set of samples might have poor predictive performances when applied to other samples, a robust wavelength region is required to render the spectral index generally applicable, regardless of the leaf surface or plant species. RESULTS The Modified Datt (MDATT) index, which is the ratio of reflectance difference defined as (Rλ3 - Rλ1)/(Rλ3 - Rλ2), exhibited the strongest correlation (R2 = 0.856, RMSE = 6.872 μg/cm2), with LCC of all the indices tested when all the leaf samples from the adaxial and abaxial surfaces were combined. The optimal wavelength regions, which were derived from the contour maps of R2 between the MDATT index and LCC for the datasets of one side or both leaf surfaces of each plant species and their intersection, indicated that the red-edge to near-infrared wavelength (723-885 nm) was optimal for λ1, while the red-edge region (697-771 nm) was optimal for λ2 and λ3. In these optimal wavelength regions, when the MDATT index was used to estimate LCC, an R2 higher than 0.8 could be obtained. The correlation of the MDATT index with LCC was the same when the positions of λ2 and λ3 were exchanged in the index. CONCLUSIONS MDATT is proposed as an optimal index for the remote estimation of vegetation chlorophyll content across several plant species in different growth stages when reflectance from both leaf surfaces is considered. The red-edge to near-infrared wavelength (723-885 nm) for λ1, as well as the red-edge region (697-771 nm) for λ2 or λ3, are considered to be the most robust for constructing the MDATT index for estimating LCC, regardless of the leaf surface or plant species.
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Affiliation(s)
- Shan Lu
- School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Changchun, 130024 China
| | - Fan Lu
- School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Changchun, 130024 China
| | - Wenqiang You
- School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Changchun, 130024 China
| | - Zheyi Wang
- School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Changchun, 130024 China
| | - Yu Liu
- School of Geographical Sciences, Northeast Normal University, 5268 Renmin Street, Changchun, 130024 China
| | - Kenji Omasa
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo, 113-8657 Japan
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Otegui MS. Vacuolar degradation of chloroplast components: autophagy and beyond. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:741-750. [PMID: 28992297 DOI: 10.1093/jxb/erx234] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/10/2017] [Indexed: 05/21/2023]
Abstract
Chloroplast degradation during natural or stress-induced senescence requires the participation of both plastidic and extraplastidic degradative pathways. As part of the extraplastidic pathways, chloroplasts export stroma, envelope, and thylakoid proteins in membrane-bound organelles that are ultimately degraded in vacuoles. Some of these pathways, such as the formation of senescence-associated vacuoles (SAVs) and CV-containing vesicles (CCVs), do not depend on autophagy, whereas delivery of Rubisco-containing bodies (RCBs), ATI1-PS (ATG8-interacting Protein 1) bodies, and small starch-like granule (SSLG) bodies is autophagy dependent. In addition, autophagy of entire chloroplasts delivers damaged chloroplasts into the vacuolar lumen for degradation. This review summarizes the autophagy-dependent and independent trafficking mechanisms by which plant cells degrade chloroplast components in vacuoles.
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Affiliation(s)
- Marisa S Otegui
- Laboratory of Cell and Molecular Biology and Departments of Botany and Genetics, University of Wisconsin-Madison, WI, USA
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Kuai B, Chen J, Hörtensteiner S. The biochemistry and molecular biology of chlorophyll breakdown. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:751-767. [PMID: 28992212 DOI: 10.1093/jxb/erx322] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Chlorophyll breakdown is one of the most obvious signs of leaf senescence and fruit ripening. The resulting yellowing of leaves can be observed every autumn, and the color change of fruits indicates their ripening state. During these processes, chlorophyll is broken down in a multistep pathway, now termed the 'PAO/phyllobilin' pathway, acknowledging the core enzymatic breakdown step catalysed by pheophorbide a oxygenase, which determines the basic linear tetrapyrrole structure of the products of breakdown that are now called 'phyllobilins'. This review provides an update on the PAO/phyllobilin pathway, and focuses on recent biochemical and molecular progress in understanding phyllobilin-modifying reactions as the basis for phyllobilin diversity, on the evolutionary diversity of the pathway, and on the transcriptional regulation of the pathway genes.
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Affiliation(s)
- Benke Kuai
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai, China
| | - Junyi Chen
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Fudan University, Shanghai, China
| | - Stefan Hörtensteiner
- Institute of Plant and Microbial Biology, University of Zurich, Zollikerstrasse, Zurich, Switzerland
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Chlorophyll degradation in aqueous mediums induced by light and UV-B irradiation: An UHPLC-ESI-MS study. Radiat Phys Chem Oxf Engl 1993 2017. [DOI: 10.1016/j.radphyschem.2017.05.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Niu Y, Chen Z, Stevens M, Sun H. Divergence in cryptic leaf colour provides local camouflage in an alpine plant. Proc Biol Sci 2017; 284:20171654. [PMID: 28978734 PMCID: PMC5647307 DOI: 10.1098/rspb.2017.1654] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 08/31/2017] [Indexed: 11/12/2022] Open
Abstract
The efficacy of camouflage through background matching is highly environment-dependent, often resulting in intraspecific colour divergence in animals to optimize crypsis in different visual environments. This phenomenon is largely unexplored in plants, although several lines of evidence suggest they do use crypsis to avoid damage by herbivores. Using Corydalis hemidicentra, an alpine plant with cryptic leaf colour, we quantified background matching between leaves and surrounding rocks in five populations based on an approximate model of their butterfly enemy's colour perception. We also investigated the pigment basis of leaf colour variation and the association between feeding risk and camouflage efficacy. We show that plants exhibit remarkable colour divergence between populations, consistent with differences in rock appearances. Leaf colour varies because of a different quantitative combination of two basic pigments-chlorophyll and anthocyanin-plus different air spaces. As expected, leaf colours are better matched against their native backgrounds than against foreign ones in the eyes of the butterfly. Furthermore, improved crypsis tends to be associated with a higher level of feeding risk. These results suggest that divergent cryptic leaf colour may have evolved to optimize local camouflage in various visual environments, extending our understanding of colour evolution and intraspecific phenotype diversity in plants.
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Affiliation(s)
- Yang Niu
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan, China
| | - Zhe Chen
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Martin Stevens
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Penryn TR10 9FE, UK
| | - Hang Sun
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan, China
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Us-Camas R, Castillo-Castro E, Aguilar-Espinosa M, Limones-Briones V, Rivera-Madrid R, Robert-Díaz ML, De-la-Peña C. Assessment of molecular and epigenetic changes in the albinism of Agave angustifolia Haw. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 263:156-167. [PMID: 28818371 DOI: 10.1016/j.plantsci.2017.07.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 06/09/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
Albinism in plants is a rare phenomenon that occurs in nature and is characterized by the total or partial loss of photosynthetic pigments. Although progress has been made in understanding the nature of this phenomenon, the precise causes and biological basis are still unexplored. Here, we study the genetic and epigenetic differences between green (G), variegated (V) and albino (A) A. angustifolia Haw. plantlets obtained by in vitro propagation in order to present new insights into albinism from a plant system that offers a unique set of biological phenotypic characteristics. Low transcript levels of genes involved in carotenoids and photosynthesis such as PSY, PDS, LCYƐ, rubS, PEPCase and LHCP suggest a disruption in these processes in albino plants. Due to a high level of genetic similarity being found between the three phenotypes, we analyzed global DNA methylation and different histone marks (H3K4me2, H3K36me2, H3K9ac, H3K9me2 and H3K27me3). Although no significant differences in global 5-methyl deoxicytidine were found, almost a 2-4.5-fold increase in H3K9ac was observed in albino plants in comparison with variegated or green plants, suggesting a change in chromatin compaction related to A. angustifolia albinism.
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Affiliation(s)
- Rosa Us-Camas
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Eduardo Castillo-Castro
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Margarita Aguilar-Espinosa
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Verónica Limones-Briones
- Unidad de Recursos Naturales, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Renata Rivera-Madrid
- Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Manuel L Robert-Díaz
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico
| | - Clelia De-la-Peña
- Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130 x 32 y 34. Col. Chuburná de Hidalgo, 97205 Mérida, Yucatán, Mexico.
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Bhattacharya R, Osburn CL. Multivariate Analyses of Phytoplankton Pigment Fluorescence from a Freshwater River Network. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:6683-6690. [PMID: 28510426 DOI: 10.1021/acs.est.6b05880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Monitoring phytoplankton classes in river networks is critical to understanding phytoplankton dynamics and to predicting the ecosystem response to changing land-use and seasons. Applicability of phytoplankton fluorescence as a quick and effective ecological monitoring approach is relatively unexplored in freshwater ecosystems. We used multivariate analyses of fluorescence from pigment extracted in 90% acetone to assess the variability in phytoplankton classes, herbivory, and organic matter quality in a freshwater river network. A total of four models developed by the parallel factor analysis (PARAFAC) of fluorescence excitation and emission matrices identified six components: Model 1 (pheophytin-A and chlorophyll-A), Model 2 (chlorophyll-B and chlorophyll-C), Model 3 (pheophytin-B), and Model 4 (pheophytin-C). Redundancy analyses revealed that in the summer, urban and agricultural streams were abundant in chlorophylls, fresh organic matter, and organic nitrogen, whereas in winter, streams were high in phaeopigments. A slow-moving, light-limited wetland stream was an exception as high phaeopigment abundance was observed in both seasons. The PARAFAC components were used to develop a partial least-squares regression-based model (r2 = 0.53; Nash-Sutcliffe efficiency = 0.5; n = 147) that successfully predicted chlorophyll-A concentrations from an external subset of river water samples (r2 = 0.41; p < 0.0001; n = 75). Thus, combining multivariate analyses and fluorescence spectroscopy is useful for monitoring and predicting phytoplankton dynamics in large river networks.
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Affiliation(s)
- Ruchi Bhattacharya
- Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University , Raleigh, North Carolina 27606, United States
| | - Christopher L Osburn
- Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University , Raleigh, North Carolina 27606, United States
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Dobrikova AG, Yotsova EK, Börner A, Landjeva SP, Apostolova EL. The wheat mutant DELLA-encoding gene (Rht-B1c) affects plant photosynthetic responses to cadmium stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 114:10-18. [PMID: 28246038 DOI: 10.1016/j.plaphy.2017.02.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/18/2017] [Accepted: 02/16/2017] [Indexed: 05/03/2023]
Abstract
Тhe sensitivity to cadmium (Cd) stress of two near-isogenic wheat lines with differences at the Rht-B1 locus, Rht-B1a (tall wild type, encoding DELLA proteins) and Rht-B1c (dwarf mutant, encoding modified DELLA proteins), was investigated. The effects of 100 μM CdCl2 on plant growth, pigment content and functional activity of the photosynthetic apparatus of wheat seedlings grown on a nutrient solution were evaluated through a combination of PAM chlorophyll fluorescence, oxygen evolution, oxidation-reduction kinetics of P700 and 77 K fluorescence. The results showed that the wheat mutant (Rht-B1c) was more tolerant to Cd stress compared to the wild type (Rht-B1a), as evidenced by the lower reductions in plant growth and pigment content, lower inhibition of photosystem I (PSI) and photosystem II (PSII) photochemistry and of the oxygen evolution measured with Clark-type and Joliot-type electrodes. Furthermore, the enhanced Cd tolerance was accompanied by increased Cd accumulation within mutant plant tissues. The molecular mechanisms through which the Rht-B1c mutation improves plant tolerance to Cd stress involve structural alterations in the mutant photosynthetic membranes leading to better protection of the Mn cluster of oxygen-evolving complex and increased capacity for PSI cyclic electron transport, protecting photochemical activity of the photosynthetic apparatus under stress. This study suggests a role for the Rht-B1c-encoded DELLA proteins in protective mechanisms and tolerance of the photosynthetic apparatus in wheat plants exposed to heavy metals stress.
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Affiliation(s)
- Anelia G Dobrikova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
| | - Ekaterina K Yotsova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Andreas Börner
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Stadt Seeland, OT Gatersleben, Germany
| | - Svetlana P Landjeva
- Institute of Plant Physiology and Genetics, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Emilia L Apostolova
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
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Li C, Wurst K, Jockusch S, Gruber K, Podewitz M, Liedl KR, Kräutler B. Chlorophyll-Derived Yellow Phyllobilins of Higher Plants as Medium-Responsive Chiral Photoswitches. Angew Chem Int Ed Engl 2016; 55:15760-15765. [PMID: 27891749 PMCID: PMC5248603 DOI: 10.1002/anie.201609481] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Indexed: 11/20/2022]
Abstract
The fall colors are signs of chlorophyll breakdown, the biological process in plants that generates phyllobilins. Most of the abundant natural phyllobilins are colorless, but yellow phyllobilins (phylloxanthobilins) also occur in fall leaves. As shown here, phylloxanthobilins are unique four-stage photoswitches. Which switching mode is turned on is controlled by the molecular environment. In polar media, phylloxanthobilins are monomeric and undergo photoreversible Z/E isomerization, similar to that observed for bilirubin. Unlike bilirubin, however, the phylloxanthobilin Z isomers photodimerize in apolar solvents by regio- and stereospecific thermoreversible [2+2] cycloadditions from self-assembled hydrogen-bonded dimers. X-ray analysis revealed the first stereostructure of a phylloxanthobilin and its hydrogen-bonded self-templating architecture, helping to rationalize its exceptional photoswitch features. The chemical behavior of phylloxanthobilins will play a seminal role in identifying biological roles of phyllobilins.
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Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of Innsbruck6020InnsbruckAustria
| | - Klaus Wurst
- Institute of General, Inorganic & Theoretical ChemistryUniversity of InnsbruckAustria
| | | | - Karl Gruber
- Institute of Molecular BiosciencesUniversity of GrazAustria
| | - Maren Podewitz
- Institute of General, Inorganic & Theoretical Chemistry and Centre of Molecular BiosciencesUniversity of InnsbruckAustria
| | - Klaus R. Liedl
- Institute of General, Inorganic & Theoretical Chemistry and Centre of Molecular BiosciencesUniversity of InnsbruckAustria
| | - Bernhard Kräutler
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of Innsbruck6020InnsbruckAustria
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Li C, Wurst K, Jockusch S, Gruber K, Podewitz M, Liedl KR, Kräutler B. Von Chlorophyll abstammende gelbe Phyllobiline höherer Pflanzen als umgebungsgesteuerte, chirale Photoschalter. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201609481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Chengjie Li
- Institut für Organische Chemie und Centrum für Molekulare Biowissenschaften; Universität Innsbruck; 6020 Innsbruck Österreich
| | - Klaus Wurst
- Institut für Allgemeine, Anorganische & Theoretische Chemie; Universität Innsbruck; Österreich
| | | | - Karl Gruber
- Institut für Molekulare Biowissenschaften; Universität Graz; Österreich
| | - Maren Podewitz
- Institut für Allgemeine, Anorganische & Theoretische Chemie und Centrum für Molekulare Biowissenschaften; Universität Innsbruck; Österreich
| | - Klaus R. Liedl
- Institut für Allgemeine, Anorganische & Theoretische Chemie und Centrum für Molekulare Biowissenschaften; Universität Innsbruck; Österreich
| | - Bernhard Kräutler
- Institut für Organische Chemie und Centrum für Molekulare Biowissenschaften; Universität Innsbruck; 6020 Innsbruck Österreich
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Erhart T, Mittelberger C, Vergeiner C, Scherzer G, Holzner B, Robatscher P, Oberhuber M, Kräutler B. Chlorophyll Catabolites in Senescent Leaves of the Plum Tree (Prunus domestica). Chem Biodivers 2016; 13:1441-1453. [PMID: 27533340 PMCID: PMC5123584 DOI: 10.1002/cbdv.201600181] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/10/2016] [Indexed: 12/28/2022]
Abstract
In cold extracts of senescent leaves of the plum tree (Prunus domestica ssp. domestica), six colorless non-fluorescent chlorophyll catabolites (NCCs) were characterized, named Pd-NCCs. In addition, several minor NCC fractions were tentatively classified. The structure of the most polar one of the NCCs, named Pd-NCC-32, featured an unprecedented twofold glycosidation pattern. Three of the NCCs are also functionalized at their 32 -position by a glucopyranosyl group. In addition, two of these glycosidated NCCs carry a dihydroxyethyl group at their 18-position. In the polar Pd-NCC-32, the latter group is further glycosidated at the terminal 182 -position. Four other major Pd-NCCs and one minor Pd-NCC were identified with five NCCs from higher plants known to belong to the 'epi'-series. In addition, tentative structures were derived for two minor fractions, classified as yellow chlorophyll catabolites, which represented (formal) oxidation products of two of the observed Pd-NCCs. The chlorophyll catabolites in leaves of plum feature the same basic structural pattern as those found in leaves of apple and pear trees.
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Affiliation(s)
- Theresia Erhart
- Institute of Organic Chemistry and Center of Molecular BiosciencesUniversity of InnsbruckInnrain 80/82AT‐6020Innsbruck
| | - Cecilia Mittelberger
- Laimburg Research Centre for Agriculture and ForestryLaimburg 6 – Pfatten (Vadena)IT‐39040Auer (Ora)BZ
| | - Clemens Vergeiner
- Institute of Organic Chemistry and Center of Molecular BiosciencesUniversity of InnsbruckInnrain 80/82AT‐6020Innsbruck
| | - Gerhard Scherzer
- Institute of Organic Chemistry and Center of Molecular BiosciencesUniversity of InnsbruckInnrain 80/82AT‐6020Innsbruck
| | - Barbara Holzner
- Laimburg Research Centre for Agriculture and ForestryLaimburg 6 – Pfatten (Vadena)IT‐39040Auer (Ora)BZ
| | - Peter Robatscher
- Laimburg Research Centre for Agriculture and ForestryLaimburg 6 – Pfatten (Vadena)IT‐39040Auer (Ora)BZ
| | - Michael Oberhuber
- Laimburg Research Centre for Agriculture and ForestryLaimburg 6 – Pfatten (Vadena)IT‐39040Auer (Ora)BZ
| | - Bernhard Kräutler
- Institute of Organic Chemistry and Center of Molecular BiosciencesUniversity of InnsbruckInnrain 80/82AT‐6020Innsbruck
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Thomas H, Ougham H. Introduction to a Virtual Issue on plant senescence. THE NEW PHYTOLOGIST 2016; 212:531-536. [PMID: 27735076 DOI: 10.1111/nph.14248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Howard Thomas
- IBERS, Aberystwyth University, Edward Llwyd Building, Aberystwyth, Ceredigion, SY23 3DA, UK.
| | - Helen Ougham
- IBERS, Aberystwyth University, Edward Llwyd Building, Aberystwyth, Ceredigion, SY23 3DA, UK
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45
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Engaging with the Canopy—Multi-Dimensional Vegetation Mark Visualisation Using Archived Aerial Images. REMOTE SENSING 2016. [DOI: 10.3390/rs8090752] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Sozzi GO, Fraschina AA, Castro MA. Ripening-Associated Microstructural Changes in Antisense ACC Synthase Tomato Fruit. FOOD SCI TECHNOL INT 2016. [DOI: 10.1106/marw-6nur-gu3h-d2el] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The ultrastructural impact of low ethylene biosynthesis (less than 0.5% of normal levels) was evaluated in transgenic (A11.1) tomatoes ( Lycopersicon esculentumMill.) expressing an antisense 1-aminocyclopropane-1-carboxylic acid synthase (ACC-S) transgene by means of transmission and environmental scanning electron microscopy. In 48-day mature green fruit, no significant ultrastructural differences were found between transgenic and control tomatoes. In 78-day control fruit, which were overripe and showed deteriorated texture, many areas of the cytoplasm were devoid of structures, and micrographs showed cell collapse with folding and dissolution of the cell wall. On the other hand, in 90-day transgenic fruit, which were firm and not ripe, the cytoplasm showed a relatively high electron density. Plastids retained remnants of chloroplast thylakoids along with significant amounts of osmiophylic plastoglobuli, but lycopene was not detected. Conspicuous starch granules were observed in mature green transgenic tomatoes, but were not detected in 90-day chlorochromoplasts. Electron-dense regions reflecting the integrity of the middle lamella alternated with other partially degraded regions. This incipient dissolution of the middle lamella pectic polymers may be attributable to nonenzymatic deaggregation or to cell-wall hydrolases which could be ethylene independent or responsive to very low levels of ethylene. Besides, cells were attached along extended contact areas and appeared turgid. This feature may provide an explanation of firmness retention that does not solely involve cell walls. Disruption of the middle lamella and development of lycopene crystalloids were observed when exogenous ethylene (12 ppm) was applied.
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Affiliation(s)
- G. O. Sozzi
- Cátedra de Bioquímica, Departamento de Biología Aplicada y Alimentos, Facultad de Agronomía, Universidad de Buenos Aires, Avda. San Martín 4453, C1417 DSE, Buenos Aires, Argentina
| | - A. A. Fraschina
- Cátedra de Bioquímica, Departamento de Biología Aplicada y Alimentos, Facultad de Agronomía, Universidad de Buenos Aires, Avda. San Martín 4453, C1417 DSE, Buenos Aires, Argentina
| | - M. A. Castro
- Laboratorio de Anatomía Vegetal, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, C1428 EHA, Buenos Aires, Argentina
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Kräutler B. Breakdown of Chlorophyll in Higher Plants--Phyllobilins as Abundant, Yet Hardly Visible Signs of Ripening, Senescence, and Cell Death. Angew Chem Int Ed Engl 2016; 55:4882-907. [PMID: 26919572 PMCID: PMC4950323 DOI: 10.1002/anie.201508928] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Indexed: 01/06/2023]
Abstract
Fall colors have always been fascinating and are still a remarkably puzzling phenomenon associated with the breakdown of chlorophyll (Chl) in leaves. As discovered in recent years, nongreen bilin-type Chl catabolites are generated, which are known as the phyllobilins. Collaborative chemical-biological efforts have led to the elucidation of the key Chl-breakdown processes in senescent leaves and in ripening fruit. Colorless and largely photoinactive phyllobilins are rapidly produced from Chl, apparently primarily as part of a detoxification program. However, fluorescent Chl catabolites accumulate in some senescent leaves and in peels of ripe bananas and induce a striking blue glow. The structural features, chemical properties, and abundance of the phyllobilins in the biosphere suggest biological roles, which still remain to be elucidated.
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Affiliation(s)
- Bernhard Kräutler
- Institute of Organic Chemistry & Center of Molecular Biosciences (CMBI), University of Innsbruck, 6020, Innsbruck, Austria.
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Kräutler B. Der Chlorophyllabbau in höheren Pflanzen - Phyllobiline als weitverbreitete, aber kaum sichtbare Zeichen von Reifung, Seneszenz und Zelltod. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201508928] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Bernhard Kräutler
- Institut für Organische Chemie & Centrum für MolekulareBiowissenschaften (CMBI); Universität Innsbruck; 6020 Innsbruck Österreich
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Li C, Kräutler B. Transition metal complexes of phyllobilins - a new realm of bioinorganic chemistry. Dalton Trans 2016; 44:10116-27. [PMID: 25923782 PMCID: PMC4447063 DOI: 10.1039/c5dt00474h] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Phyllobilins may function as natural ligand molecules for biologically important transition metal ions, giving complexes with remarkable chemical and photophysical properties.
Natural cyclic tetrapyrroles feature outstanding capacity for binding transition metal ions, furnishing Nature with the important metallo-porphyrinoid ‘Pigments of Life’, such as heme, chlorophyll (Chl) and vitamin B12. In contrast, linear tetrapyrroles are not generally ascribed a biologically relevant ability for metal-binding. Indeed, when heme or Chl are degraded to natural linear tetrapyrroles, their central Fe- or Mg-ions are set free. Some linear tetrapyrroles are, however, effective multi-dentate ligands and their transition metal complexes have remarkable chemical properties. The focus of this short review is centred on such complexes of the linear tetrapyrroles derived from natural Chl-breakdown, called phyllobilins. These natural bilin-type compounds are massively produced in Nature and in highly visible processes. Colourless non-fluorescing Chl-catabolites (NCCs) and the related dioxobilin-type NCCs, which typically accumulate in leaves as ‘final’ products of Chl-breakdown, show low affinity for transition metal-ions. However, NCCs are oxidized in leaves to give less saturated coloured phyllobilins, such as yellow or pink Chl-catabolites (YCCs or PiCCs). YCCs and PiCCs are ligands for various biologically relevant transition metal-ions, such as Zn(ii)-, Ni(ii)- and Cu(ii)-ions. Complexation of Zn(ii)- and Cd(ii)-ions by the effectively tridentate PiCC produces blue metal-complexes that exhibit an intense red fluorescence, thus providing a tool for the sensitive detection of these metal ions. Outlined here are fundamental aspects of structure and metal coordination of phyllobilins, including a comparison with the corresponding properties of bilins. This knowledge may be valuable in the quest of finding possible biological roles of the phyllobilins. Thanks to their capacity for metal-ion coordination, phyllobilins could, e.g., be involved in heavy-metal transport and detoxification, and some of their metal-complexes could act as sensitizers for singlet oxygen or as plant toxins against pathogens.
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Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry & Centre of Molecular Biosciences, University of Innsbruck, Innrain 80/82, A-6020 Innsbruck, Austria.
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Remote Sensing Based Simple Models of GPP in Both Disturbed and Undisturbed Piñon-Juniper Woodlands in the Southwestern U.S. REMOTE SENSING 2015. [DOI: 10.3390/rs8010020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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