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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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2
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Perez-Ortiz G, Sidda JD, Peate J, Ciccarelli D, Ding Y, Barry SM. Production of copropophyrin III, biliverdin and bilirubin by the rufomycin producer, Streptomyces atratus. Front Microbiol 2023; 14:1092166. [PMID: 37007481 PMCID: PMC10060970 DOI: 10.3389/fmicb.2023.1092166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/31/2023] [Indexed: 03/18/2023] Open
Abstract
Heme is best known for its role as a versatile prosthetic group in prokaryotic and eukaryotic proteins with diverse biological functions including gas and electron transport, as well as a wide array of redox chemistry. However, free heme and related tetrapyrroles also have important roles in the cell. In several bacterial strains, heme biosynthetic precursors and degradation products have been proposed to function as signaling molecules, ion chelators, antioxidants and photoprotectants. While the uptake and degradation of heme by bacterial pathogens is well studied, less is understood about the physiological role of these processes and their products in non-pathogenic bacteria. Streptomyces are slow growing soil bacteria known for their extraordinary capacity to produce complex secondary metabolites, particularly many clinically used antibiotics. Here we report the unambiguous identification of three tetrapyrrole metabolites from heme metabolism, coproporphyrin III, biliverdin and bilirubin, in culture extracts of the rufomycin antibiotic producing Streptomyces atratus DSM41673. We propose that biliverdin and bilirubin may combat oxidative stress induced by nitric oxide production during rufomycin biosynthesis, and indicate the genes involved in their production. This is, to our knowledge, the first report of the production of all three of these tetrapyrroles by a Streptomycete.
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Affiliation(s)
| | | | | | | | | | - Sarah M. Barry
- Department of Chemistry, Faculty of Natural & Mathematical Sciences, King’s College London, London, United Kingdom
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Jung W, Lee DY, Moon E, Jon S. Nanoparticles derived from naturally occurring metal chelators for theranostic applications. Adv Drug Deliv Rev 2022; 191:114620. [PMID: 36379406 DOI: 10.1016/j.addr.2022.114620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/31/2022] [Accepted: 11/07/2022] [Indexed: 11/15/2022]
Abstract
Metals are indispensable for the activities of all living things, from single-celled organisms to higher organisms, including humans. Beyond their intrinsic quality as metal ions, metals help creatures to maintain requisite biological processes by forming coordination complexes with endogenous ligands that are broadly distributed in nature. These types of naturally occurring chelating reactions are found through the kingdoms of life, including bacteria, plants and animals. Mimicking these naturally occurring coordination complexes with intrinsic biocompatibility may offer an opportunity to develop nanomedicine toward clinical applications. Herein, we introduce representative examples of naturally occurring coordination complexes in a selection of model organisms and highlight such bio-inspired metal-chelating nanomaterials for theranostic applications.
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Affiliation(s)
- Wonsik Jung
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea; Center for Precision Bio-Nanomedicine, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Dong Yun Lee
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Seoul 05505, Republic of Korea; Translational Biomedical Research Group, Biomedical Research Center, Asan Institute for Life Science, Asan Medical Center, 88 Olympic-ro 43-gil, Seoul 05505, Republic of Korea.
| | - Eugene Moon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea; Center for Precision Bio-Nanomedicine, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Sangyong Jon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea; Center for Precision Bio-Nanomedicine, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Daejeon 34141, Republic of Korea.
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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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Synthesis, Characterization and Applications of Schiff Base Chemosensor for Determination of Cr(III) Ions. J Fluoresc 2022; 32:1889-1898. [PMID: 35749029 DOI: 10.1007/s10895-022-02990-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 05/31/2022] [Indexed: 10/17/2022]
Abstract
The development of a highly sensitive, selective, and efficient sensor for the determination and detection of Cr(III) ions remains a great challenge. Recently, some fluorescent chemosensors have been developed for the recognition of Cr(III) ions. But, the main drawbacks of the reported fluorescent chemosensors are the lack of selectivity and interference of anions and other trivalent cations. Herein, we designed and synthesized a novel thiazole-based fluorescent and colorimetric Schiff base chemosensor SB2 for the detection of Cr(III) ion by chemodosimetric approach. Using different analytical techniques including UV-vis, 13C-NMR, 1H-NMR, and FT-IR analysis the chemosensor SB2 was structurally characterized. The fully characterized chemosensor SB2 was used for the spectrofluorimetric and colorimetric detection of Cr(III) ions. Interestingly, chemosensor SB2 upon interaction with various metal cations including Ni2+, Na+, Cd2+, Ag+, Mn2+, K+, Zn2+, Cu2+, Hg2+, Co2+, Pb2+, Mg2+, Sn2+, Al3+ and Cr3+ displays highly selective and sensitive fluorescent (turn-on) and colorimetric (yellow to colorless) response toward Cr(III) ions. The fluorescence and UV-vis techniques confirmed the selective hydrolysis of azomethine group (-C = N-) of Schiff base chemosensor SB2 by Cr(III) ions. As a result, the fluorescence enhancement was observed that is corresponding to 2-hydroxy-1-nepthaldehyde (fluorophore). The chemosensor SB2 exhibits high interference performance towards Cr(III) ions over other metal cations in a wide pH range. Mover, the quite low detection limit was calculated to be 0.027 µg ml-1 (0.5 µM) (3σ/slop), lower than the maximum tolerable limits of Cr(III ions (10 µM) in drinking water permitted by the United States Environmental Protection Agency (EPA). These results show that chemosensor SB2 has great potential to detect selectively Cr(III) ions in the agricultural, environmental and biological analysis system.
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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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Cp*Ir complex with mesobiliverdin ligand isolated from Thermoleptolyngbya sp. O-77. J Organomet Chem 2022. [DOI: 10.1016/j.jorganchem.2022.122302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Tomat E, Curtis CJ. Biopyrrin Pigments: From Heme Metabolites to Redox-Active Ligands and Luminescent Radicals. Acc Chem Res 2021; 54:4584-4594. [PMID: 34870973 DOI: 10.1021/acs.accounts.1c00613] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox-active ligands in coordination chemistry not only modulate the reactivity of the bound metal center but also serve as electron reservoirs to store redox equivalents. Among many applications in contemporary chemistry, the scope of redox-active ligands in biology is exemplified by the porphyrin radicals in the catalytic cycles of multiple heme enzymes (e.g., cytochrome P450, catalase) and the chlorophyll radicals in photosynthetic systems. This Account reviews the discovery of two redox-active ligands inspired by oligopyrrolic fragments found in biological settings as products of heme metabolism.Linear oligopyrroles, in which pyrrole heterocycles are linked by methylene or methine bridges, are ubiquitous in nature as part of the complex, multistep biosynthesis and degradation of hemes and chlorophylls. Bile pigments, such as biliverdin and bilirubin, are common and well-studied tetrapyrroles with characteristic pyrrolin-2-one rings at both terminal positions. The coordination chemistry of these open-chain pigments is less developed than that of porphyrins and other macrocyclic oligopyrroles; nevertheless, complexes of biliverdin and its synthetic analogs have been reported, along with fluorescent zinc complexes of phytobilins employed as bioanalytical tools. Notably, linear conjugated tetrapyrroles inherit from porphyrins the ability to stabilize unpaired electrons within their π system. The isolated complexes, however, present helical structures and generally limited stability.Smaller biopyrrins, which feature three or two pyrrole rings and the characteristic oxidized termini, have been known for several decades following their initial isolation as urinary pigments and heme metabolites. Although their coordination chemistry has remained largely unexplored, these compounds are structurally similar to the well-established tripyrrin and dipyrrin ligands employed in a broad variety of metal complexes. In this context, our study of the coordination chemistry of tripyrrin-1,14-dione and dipyrrin-1,9-dione was motivated by the potential to retain on these compact, versatile platforms the reversible ligand-based redox chemistry of larger tetrapyrrolic systems.The tripyrrindione ligand coordinates several divalent transition metals (i.e., Pd(II), Ni(II) Cu(II), Zn(II)) to form neutral complexes in which an unpaired electron is delocalized over the conjugated π system. These compounds, which are stable at room temperature and exposed to air, undergo reversible one-electron processes to access different redox states of the ligand system without affecting the oxidation state and coordination geometry of the metal center. We also characterized ligand-based radicals on the dipyrrindione platform in both homoleptic and heteroleptic complexes. In addition, this study documented noncovalent interactions (e.g., interligand hydrogen bonds with the pyrrolinone carbonyls, π-stacking of ligand-centered radicals) as important aspects of this coordination chemistry. Furthermore, the fluorescence of the zinc-bound tripyrrindione radical and the redox-switchable emission of a dipyrrindione BODIPY-type fluorophore showcased the potential interplay of redox chemistry and luminescence in these compounds. Supported by computational analyses, the portfolio of properties revealed by this investigation takes the tripyrrindione and dipyrrindione motifs of heme metabolites to the field of redox-active ligands, where they are positioned to offer new opportunities for catalysis, sensing, supramolecular systems, and functional materials.
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Affiliation(s)
- Elisa Tomat
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0041, United States
| | - Clayton J. Curtis
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721-0041, United States
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Ghidinelli S, Abbate S, Mazzeo G, Boiadjiev SE, Lightner DA, Longhi G. Biliverdin chiral derivatives as chiroptical switches for pH and metal cation sensing. Phys Chem Chem Phys 2021; 23:20138-20151. [PMID: 34551042 DOI: 10.1039/d1cp02571f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of six optically active derivatives of the bile pigment biliverdin, namely (βS,β'S)-dimethylmesobiliverdin-XIIIα, cyclic esters of linear diols [HO(CH2)nOH] where n = 1-6, have been investigated by vibrational circular dichroism (VCD) and density functional theory (DFT) calculations. The results were correlated with the length (n) of the diester belt, the verdin helicity and an M ⇄ P conformational equilibrium - as previously shown by electronic circular dichroism (ECD). Furthermore, ECD spectra have been found to be quite sensitive to solvent nature and pH. TD-DFT calculations of the protonated/deprotonated verdins with n = 1 and 2 diester belts respectively have allowed one, moreover, to explain the spectroscopic data in terms of a change in the M ⇄ P equilibrium. Finally, the set of investigated compounds, together with other chirally functionalized "non-belted" biliverdin analogs, has also been found to be sensitive to the presence of metal ions, with which the verdins chelate. On the basis of ECD and VCD data, we propose that the spectroscopic changes observed are consistent with self-association (dimerization) of the verdin molecules promoted by the metal cations, as bolstered by DFT calculations, and for which a dimerization constant of 73 000 M-1 is evaluated. We envision the use of current chiroptical spectroscopies in connection with chiral biliverdin derivatives as natural sensors or probes of the micro-environmental conditions, such as pH or the presence of metal ions.
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Affiliation(s)
- Simone Ghidinelli
- Università di Brescia, Dipartimento di Medicina Molecolare e Traslazionale, Viale Europa 11, 25123 Brescia, Italy.
| | - Sergio Abbate
- Università di Brescia, Dipartimento di Medicina Molecolare e Traslazionale, Viale Europa 11, 25123 Brescia, Italy. .,Istituto Nazionale di Ottica (INO), C.N.R., Research Unit of Brescia, via Branze 45, 25123 Brescia, Italy
| | - Giuseppe Mazzeo
- Università di Brescia, Dipartimento di Medicina Molecolare e Traslazionale, Viale Europa 11, 25123 Brescia, Italy.
| | - Stefan E Boiadjiev
- Regional Health Inspectorate, 7 Prince Al. Battenberg I Str., 5800 Pleven, Bulgaria
| | - David A Lightner
- Chemistry Department, University of Nevada, Reno, NV, 89557, USA
| | - Giovanna Longhi
- Università di Brescia, Dipartimento di Medicina Molecolare e Traslazionale, Viale Europa 11, 25123 Brescia, Italy. .,Istituto Nazionale di Ottica (INO), C.N.R., Research Unit of Brescia, via Branze 45, 25123 Brescia, Italy
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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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Sobolevsky T, Ahrens B. Measurement of urinary cobalt as its complex with 2-(5-chloro-2-pyridylazo)-5-diethylaminophenol by liquid chromatography-tandem mass spectrometry for the purpose of anti-doping control. Drug Test Anal 2021; 13:1145-1157. [PMID: 33484083 DOI: 10.1002/dta.3004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 01/23/2023]
Abstract
Cobalt is well known for its ability to stimulate erythropoiesis via stabilization of hypoxia-inducible factors. In sports, this can provide a competitive benefit to athletes, so the World Anti-Doping Agency prohibits the use of cobalt in any form except its cobalamin vitamers. As of now, cobalt in biological fluids is detected by inductively coupled plasma mass spectrometry (ICP-MS), a technique which has very limited availability in anti-doping laboratories. Therefore, a quantitative method based on liquid chromatography-tandem mass spectrometry capable of measuring urinary cobalt in the form of its complex with 2-(5-chloro-2-pyridylazo)-5-diethylaminophenol (5-Cl-PADAP) has been developed and validated. A cobalt complex with deuterium-labeled 5-Cl-PADAP was used as internal standard. The method was found linear over the concentration range of 5-500 ng/ml with a combined standard uncertainty less than 10% at 15, 200, and 450 ng/ml. Stability of cobalt ions in urine was investigated over the course of 2 months; the concentration of free Co2+ was observed to decline by approximately 50% but restored upon hydrolysis with hydrochloric acid. Unlike ICP-MS, this method is practically unaffected by the presence of cyanocobalamin as the latter is resistant to acid hydrolysis. Notwithstanding the lack of formalized threshold concentration of cobalt in urine, it is highly desirable that more anti-doping laboratories engage in testing for cobalt levels to better understand the prevalence of cobalt misuse in athletes. Given that cobalt salts are inexpensive and easily obtainable, the risk of such abuse should not be underestimated.
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Affiliation(s)
- Tim Sobolevsky
- UCLA Olympic Analytical Laboratory, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, California, Los Angeles, USA
| | - Brian Ahrens
- UCLA Olympic Analytical Laboratory, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, California, Los Angeles, USA
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Diana R, Panunzi B. The Role of Zinc(II) Ion in Fluorescence Tuning of Tridentate Pincers: A Review. Molecules 2020; 25:molecules25214984. [PMID: 33126503 PMCID: PMC7662684 DOI: 10.3390/molecules25214984] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/20/2020] [Accepted: 10/25/2020] [Indexed: 12/17/2022] Open
Abstract
Tridentate ligands are simple low-cost pincers, easy to synthetize, and able to guarantee stability to the derived complexes. On the other hand, due to its unique mix of structural and optical properties, zinc(II) ion is an excellent candidate to modulate the emission pattern as desired. The present work is an overview of selected articles about zinc(II) complexes showing a tuned fluorescence response with respect to their tridentate ligands. A classification of the tridentate pincers was carried out according to the binding donor atom groups, specifically nitrogen, oxygen, and sulfur donor atoms, and depending on the structure obtained upon coordination. Fluorescence properties of the ligands and the related complexes were compared and discussed both in solution and in the solid state, keeping an eye on possible applications.
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Fathi P, Pan D. Current trends in pyrrole and porphyrin-derived nanoscale materials for biomedical applications. Nanomedicine (Lond) 2020; 15:2493-2515. [PMID: 32975469 PMCID: PMC7610151 DOI: 10.2217/nnm-2020-0125] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 08/14/2020] [Indexed: 02/01/2023] Open
Abstract
This article is written to provide an up-to-date review of pyrrole-based biomedical materials. Porphyrins and other tetrapyrrolic molecules possess unique magnetic, optical and other photophysical properties that make them useful for bioimaging and therapy. This review touches briefly on some of the synthetic strategies to obtain porphyrin- and tetrapyrrole-based nanoparticles, as well as the variety of applications in which crosslinked, self-assembled, porphyrin-coated and other nanoparticles are utilized. We explore examples of these nanoparticles' applications in photothermal therapy, drug delivery, photodynamic therapy, stimuli response, fluorescence imaging, photoacoustic imaging, magnetic resonance imaging, computed tomography and positron emission tomography. We anticipate that this review will provide a comprehensive summary of pyrrole-derived nanoparticles and provide a guideline for their further development.
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Affiliation(s)
- Parinaz Fathi
- Departments of Bioengineering, Materials Science & Engineering & Beckman Institute, University of Illinois, Urbana, IL 61801, USA
- Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL 61801, USA
| | - Dipanjan Pan
- Departments of Bioengineering, Materials Science & Engineering & Beckman Institute, University of Illinois, Urbana, IL 61801, USA
- Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, IL 61801, USA
- Departments of Diagnostic Radiology & Nuclear Medicine & Pediatrics, University of Maryland Baltimore, Health Sciences Facility III, 670 W Baltimore St., Baltimore, MD 21201, USA
- Department of Chemical, Biochemical & Environmental Engineering, University of Maryland Baltimore County, Interdisciplinary Health Sciences Facility, 1000 Hilltop Circle Baltimore, MD 21250, USA
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Roca M, Pérez-Gálvez A. Profile of Chlorophyll Catabolites in Senescent Leaves of Epipremnun aureum Includes a Catabolite Esterified with Hydroxytyrosol 1- O-Glucoside. JOURNAL OF NATURAL PRODUCTS 2020; 83:873-880. [PMID: 32134654 DOI: 10.1021/acs.jnatprod.9b00546] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Despite the fact that chlorophyll degradation is a physiological phenomenon occurring daily in all photosynthetic tissues, chlorophyll catabolites are not fully identified. Three new forms (1, 3, and 4) of linear chlorophyll catabolites (phyllobilins) have been characterized in senescent leaves of Epipremnun aureum with spectroscopic data. Compound 1 is a hypermodified blue fluorescent chlorophyll catabolite (hmFCC) esterified with the potent antioxidant hydroxytyrosol. The sequestration of this phenol by a chlorophyll catabolite could explain the physiological meaning of the persistence of hmFCCs in some senescent plants. Compound 3, a yellow chlorophyll catabolite (YCC) originated from the oxidation at C-15 of 1. YCCs have been identified previously and are exclusively formed in the plant vacuole from the final nonfluorescent chlorophyll catabolites (NCCs). The presence of 3 in leaves implies a new reaction in chlorophyll catabolism, as the characterization of 3 implies that YCCs can be also be oxidized in the cytosol from FCCs. Finally, phyllobilin 4 represents a new type of YCC characterized by an inflexible bicyclo glucosyl moiety linked through an intramolecular esterification of the propionic acid residue with the C-3 hydroxy group. The corresponding NCC precursor was recently identified and now the characterization of 4 shows that even this rigid structure can be further oxidized. Undoubtedly, the characterization of phyllobilins is essential to completely comprehend chlorophyll degradation.
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Affiliation(s)
- María Roca
- Food Phytochemistry Department, Instituto de la Grasa (CSIC), University Campus, Building 46, 41013 Sevilla, Spain
| | - Antonio Pérez-Gálvez
- Food Phytochemistry Department, Instituto de la Grasa (CSIC), University Campus, Building 46, 41013 Sevilla, Spain
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15
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Dimitrijević MS, Bogdanović Pristov J, žiŽić M, Stanković DM, Bajuk-Bogdanović D, Stanić M, Spasić S, Hagen W, Spasojević I. Biliverdin-copper complex at physiological pH. Dalton Trans 2019; 48:6061-6070. [PMID: 30734795 DOI: 10.1039/c8dt04724c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Biliverdin (BV), a product of heme catabolism, is known to interact with transition metals, but the details of such interactions under physiological conditions are scarce. Herein, we examined coordinate/redox interactions of BV with Cu2+ in phosphate buffer at pH 7.4, using spectrophotometry, HESI-MS, Raman spectroscopy, 1H NMR, EPR, fluorimetry, and electrochemical methods. BV formed a stable coordination complex with copper in 1 : 1 stoichiometry. The structure of BV was more planar and energetically stable in the complex. The complex showed strong paramagnetic effects that were attributed to an unpaired delocalized e-. The delocalized electron may come from BV or Cu2+, so the complex is formally composed either of BV radical cation and Cu1+ or of BV radical anion and Cu3+. The complex underwent oxidation only in the presence of both O2 and an excess of Cu2+, or a strong oxidizing agent, and it was resistant to reducing agents. The biological effects of the stable BV metallocomplex containing a delocalized unpaired electron should be further examined, and may provide an answer to the long-standing question of high energy investment in the catabolism of BV, which represents a relatively harmless molecule per se.
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Affiliation(s)
- Milena S Dimitrijević
- Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11030 Belgrade, Serbia.
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16
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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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17
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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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18
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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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19
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Gautam R, Petritis SJ, Astashkin AV, Tomat E. Paramagnetism and Fluorescence of Zinc(II) Tripyrrindione: A Luminescent Radical Based on a Redox-Active Biopyrrin. Inorg Chem 2018; 57:15240-15246. [PMID: 30418755 DOI: 10.1021/acs.inorgchem.8b02532] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability of bilins and other biopyrrins to form fluorescent zinc complexes has been known for more than a century; however, the exact identity of the emissive species remains uncertain in many cases. Herein, we characterize the hitherto elusive zinc complex of tripyrrin-1,14-dione, an analogue of several orange urinary pigments. As previously observed for its Pd(II), Cu(II), and Ni(II) complexes, tripyrrindione binds Zn(II) as a dianionic radical and forms a paramagnetic complex carrying an unpaired electron on the ligand π-system. This species is stable at room temperature and undergoes quasi-reversible ligand-based redox chemistry. Although the complex is isolated as a coordination dimer in the solid state, optical absorption and electron paramagnetic resonance spectroscopic studies indicate that the monomer is prevalent in a tetrahydrofuran solution. The paramagnetic Zn(II) tripyrrindione complex is brightly fluorescent (λabs = 599 nm, λem = 644 nm, ΦF = 0.23 in THF), and its study provides a molecular basis for the observation, made over several decades since the 1930s, of fluorescent behavior of tripyrrindione pigments in the presence of zinc salts. The zinc-bound tripyrrindione radical is thus a new addition to the limited number of stable radicals that are fluorescent at room temperature.
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Affiliation(s)
- Ritika Gautam
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Steven J Petritis
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Andrei V Astashkin
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Elisa Tomat
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
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20
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Li C, Wurst K, Berghold J, Podewitz M, Liedl KR, Kräutler B. Pyro-Phyllobilins: Elusive Chlorophyll Catabolites Lacking a Critical Carboxylate Function of the Natural Chlorophylls. Chemistry 2018; 24:2987-2998. [PMID: 29244236 PMCID: PMC5861670 DOI: 10.1002/chem.201705331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Indexed: 11/17/2022]
Abstract
A β-keto ester grouping is a characteristic of ring E of the chlorophylls (Chls). Its presence has also reinforced the original identification of nonfluorescent Chl catabolites (NCCs) as colorless, amphiphilic phyllobilins (PBs). Polar NCCs were also detected in higher plants, in which a free carboxyl group replaced the ring E ester group. Such NCCs are surprisingly resistant to loss of this carboxyl unit, and NCCs lacking the latter, that is, pyro-NCCs (pyNCCs), have not been reported. Intrigued by the question of the natural occurrence of pyro-phyllobilins (pyPBs), we have prepared a representative pyNCC by decarboxylation of a natural NCC. We also converted the pyNCC into its yellow oxidation product, a pyro-YCC (pyYCC). The solution structures of pyNCC and of pyYCC, and a crystal structure of the pyYCC methyl ester (pyYCC-Me) were obtained. pyYCC-Me features the same remarkable H-bonded and π-stacked dimer structure as the corresponding natural yellow Chl catabolite (YCC) with the ring E methyl ester group. Indeed, the latter substituent has little effect on the structure, as well as on the unique self-assembly and photoswitch behavior of yellow PBs.
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Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
- Present address: Key Laboratory for Advanced Materials and Institute of, Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyMeilong Rd. 130200237ShanghaiP.R. China
| | - Klaus Wurst
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Joachim Berghold
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Maren Podewitz
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Klaus R. Liedl
- Institute of General, Inorganic and Theoretical ChemistryUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
| | - Bernhard Kräutler
- Institute of Organic Chemistry and Centre of Molecular BiosciencesUniversity of InnsbruckInnrain 80/826020InnsbruckAustria
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21
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Sekhar AR, Sariki SK, Reddy RVR, Bisai A, Sahu PK, Tomar RS, Sankar J. Zwitterionic BODIPYs with large stokes shift: small molecular biomarkers for live cells. Chem Commun (Camb) 2017; 53:1096-1099. [PMID: 28054075 DOI: 10.1039/c6cc09325f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The two first examples of zwitterionic BODIPYs have been synthesized via a simple SN-Ar methodology. The molecules exhibit excellent optical behavior, such as a large Stokes shift in solution and therefore a very intense emission, and can thus avoid self-quenching. The zwitterionic nature of the molecules was unambiguously elucidated using single crystal XRD studies. The electronic conjugation was investigated by NMR, DFT (NICS (0)) and XRD analysis. Due to their inherent ionic nature, their enhanced solubility in aqueous conditions was exploited for their utility in bio-imaging and cell viability studies. These molecules demonstrate promising localization inside live yeast cells.
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Affiliation(s)
- Adiki Raja Sekhar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India.
| | - Santhosh Kumar Sariki
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India
| | - R V Ramana Reddy
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India.
| | - Alakesh Bisai
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India.
| | - Pushpendra Kumar Sahu
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India
| | - Raghuvir S Tomar
- Laboratory of Chromatin Biology, Department of Biological Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India
| | - Jeyaraman Sankar
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, 462066, India.
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22
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Abstract
“Non-fluorescent” chlorophyll catabolites (NCCs) were named “rusty pigments” originally, as they easily oxidized to yellow chlorophyll catabolites (YCCs) and other colored natural “phyllobilins.” In the present work, binding of Zn(II)-ions by YCC and its methyl ester YCC-Me, and structural investigations of the resulting Zn(II)-complexes are reported. Binding of Zn-ions to the weakly luminescent YCC or YCC-Me in DMSO produces orange-yellow complexes that exhibit strong green emission. The Zn-complex of YCC-Me was isolated and characterized by UV-vis-, fluorescence-, mass- and NMR-spectra. The data revealed a 2:1 complex, Zn(YCC-Me)[Formula: see text], in which YCC-Me serves as bidentate ligand. The Zn(II)-center in Zn(YCC-Me)[Formula: see text] is, thereby, deduced to be coordinated in a pseudo tetrahedral fashion. Formation of Zn(YCC-Me)[Formula: see text] (and of Zn(YCC)[Formula: see text] is compatible with an isomerization of the lactam form of ring D to the corresponding lactim tautomer in these neutral Zn(II)-complexes.
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Affiliation(s)
- Chengjie Li
- Institute of Organic Chemistry & Center of Molecular Biosciences, University of Innsbruck, Innrain 80/82, A-6020 Innsbruck, Austria
| | - Bernhard Kräutler
- Institute of Organic Chemistry & Center of Molecular Biosciences, University of Innsbruck, Innrain 80/82, A-6020 Innsbruck, Austria
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Mizutani T. Coupled oxidation of iron tetraarylporphyrins as a synthetic tool for linear tetrapyrroles. J PORPHYR PHTHALOCYA 2016. [DOI: 10.1142/s1088424616300044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Coupled oxidation of iron tetraphenylporphyrins was studied as a tool for preparation of various linear tetrapyrroles. We obtained two linear tetrapyrrole products, biladienone with the meso carbon retained and bilindione with one of the meso carbons eliminated. Biladienone was isolated as a 15-hydroxy derivative. Acid catalyzed elimination of water from biladienone yielded bilatrienone. Bilindione was converted to the zinc complex of 5-oxaporphyrin by reacting it with acetic anhydride and zinc acetate. The zinc complex of 5-oxaporphyrin was a labile electrophile, and readily reacted with a weak nucleophile such as methanol or ethanol. The nucleophilic ring cleavage was used to prepare a variety of bilinone derivatives with substituent at the terminal pyrrole ring. The zinc complex of 5-oxaporphyrin fluoresced red light with a quantum yield of 7%. Free base bilinone showed solvatochromism by forming proton-transferred hydrogen bonding with aprotic amide, which bears similarity to the red to far-red photochromism of phytochromes. The zinc complex of biladienone bearing long alkyl chains was used as an active layer of molecular switch, where flexible framework of linear tetrapyrrole and self-assembling properties lead to 103 fold electric current reduction by application of an external electric field. The zinc complex of biladienone showed allosteric binding to amines, where allosteric behavior was caused by its dimerization.
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Affiliation(s)
- Tadashi Mizutani
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
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Li C, Wurst K, Feng Y, Kräutler B. Synthesis, spectroscopic and crystallographic analysis of the Zn-complex of a di( β, β'-sulfoleno)pyrrin: model for Zn-complexes of bilirubin and of phylloxanthobilins. MONATSHEFTE FUR CHEMIE 2016; 147:1031-1036. [PMID: 27226652 PMCID: PMC4863038 DOI: 10.1007/s00706-016-1748-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 03/21/2016] [Indexed: 12/25/2022]
Abstract
ABSTRACT A high yield preparation, spectroscopic and crystallographic investigation of the crystalline Zn-complex of a di(β,β'-sulfoleno)pyrrin are reported here. In the brightly green fluorescent Zn-complex of the hardly luminescent di(β,β'-sulfoleno)pyrrin, the metal ion is bound by two di(β,β'-sulfoleno)pyrrin ligands, as revealed first by its mass spectra. The crystal structure of this Zn-complex of the di(β,β'-sulfoleno)pyrrin confirmed a regular 2:1 composition of the bidentate di(β,β'-sulfoleno)pyrrin ligand and the metal ion. The latter was coordinated in a distorted tetrahedral fashion, as found in other dipyrrin Zn-complexes. The here studied Zn-complex of a designed di(β,β'-sulfoleno)pyrrin ligand provides insights into the coordination properties of the proposed (2:1)- and (2:2)-complexes of phylloxanthobilin and bilirubin, respectively, which are two abundant natural bilin-type tetrapyrroles. GRAPHICAL ABSTRACT
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Affiliation(s)
- Chengjie Li
- />Institute of Organic Chemistry and Centre of Molecular Biosciences, University of Innsbruck, 6020 Innsbruck, Austria
- />School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Klaus Wurst
- />Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria
| | - Yaqing Feng
- />School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Bernhard Kräutler
- />Institute of Organic Chemistry and Centre of Molecular Biosciences, University of Innsbruck, 6020 Innsbruck, Austria
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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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26
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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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