DOCSLIB.ORG

Various Metallopheophorbides As Substrates for Chlorophyll

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Various Metallopheophorbides As Substrates for Chlorophyll Various Metallopheophorbides as Substrates for Chlorophyll Synthetase Michael Helfrich and Wolfhart Rüdiger Botanisches Institut, Universität München, Menzinger Straße 67, D-W-8000 München 19 Z. Naturforsch. 47c, 231-238 (1992); received January 29, 1992 Chlorophyllide, Zincpheophorbide a, Copperpheophorbide a, Cobaltpheophorbide a, Nickel- pheophorbide a Pheophorbide a was prepared from a mixture of chlorophylls a and b by differential extrac­ tion with HC1 and saponification. The insertion of the following metal ions was investigated: Mg, Zn, Co, Cu, Ni. In the enzyme test with chlorophyll synthetase, the metallopheophorbides fall into two categories: the Mg- and Zn-complexes are good substrates, the Co-, Cu- and Ni-complexes are neither substrates nor competitive inhibitors for the enzyme reaction. This corresponds to two categories of complex structures: Mg- and Zn-porphyrins prefer penta- coordinate square-pyramidal structures, Co-, Cu- and Ni-porphyrins prefer tetracoordinate square-planar structures. A model for substrate binding to chlorophyll synthetase is proposed. Introduction Since chemical reactions of chlorophyllides, e.g. The last step of chlorophyll biosynthesis is the modifications of the side chains, result easily in a prenylation of chlorophyllide with either geranyl- loss of the central magnesium, we investigated the geranyl diphosphate or phytyl diphosphate [1]. insertion of several metal ions into pheophorbide a The activity of chlorophyll synthetase - the en­ and the possible acceptance of the resulting metal zyme which catalyzes this step - was at first de­ complexes as substrates or competitive inhibitors tected in dark-grown (“etiolated”) seedlings [1 a, 2] of chlorophyll synthetase. but was later also described in green plants [3, 4]. Chlorophyll synthetase activity does not depend Materials and Methods on light whereas the previous biosynthetic step, Thin-layer chromatography (TLC) was per­ hydrogenation of protochlorophyllide to chloro­ formed on silica gel RP8 F254 plates (Merck) with phyllide requires continuous irradiation in An- methanol/acetone/water (64:20:16, v:v:v). For giosperms. Etiolated Angiosperm seedlings accu­ preparative separations by column chromatogra­ mulate protochlorophyllide in the dark. Proto­ phy, silica gel C-l8 (reverse phase, 55-105|i chlorophyllide is neither a substrate nor a 125 Ä, Waters) was used with the elution solvent competitive inhibitor for chlorophyll synthetase. 65% acetone containing 2 m M Hepes-KOH and Broken etioplasts prepared from dark-grown oat 1 m M Na2S20 4. Electronic absorption spectra were seedlings which contain protochlorophyllide and measured with a Lambda 2 spectrophotometer chlorophyll synthetase have therefore been incu­ (Perkin Elmer). !H NMR spectra were recorded bated with various exogenous chlorophyllides in on a 360 MHz instrument (Bruker). FAB mass order to test the substrate specificity of the enzyme spectra were obtained with a CH7a instrument [5]. It was found in these experiments that struc­ (Varian MAT). tural variations of substituents at ring A and the All operations were carried out under dim light. isocyclic ring are tolerated by the enzyme. Remov­ The solvents were saturated with argon before use. al of the central magnesium ion, i.e. formation Oxygen was removed from all reaction vessels with of pheophorbide led to nearly complete loss of argon or nitrogen. acceptance as a substrate [5]. Preparation of pheophorbide a (1) Abbreviations: Hepes, 2-[4-(2-hydroxyethyl)-l-piper- Green leaves of spinach ( Spinacea oleracea L.) azino]ethane sulfonic acid; HPLC, high performance or pea ( Pisum sativum L.) were used for isolation liquid chromatography; MS, mass spectrum; TLC, thin- layer chromatography. of a mixture of chlorophylls a + b according to Iri- yama et al. [6]. Briefly, 1 kg of leaves were frozen Verlag der Zeitschrift für Naturforschung, D-W-7400 Tübingen in liquid nitrogen, pulverized and extracted several 0939-5075/92/0300-0231 $01.30/0 times with acetone (total volume 4.5 1). The crude Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung This work has been digitalized and published in 2013 by Verlag Zeitschrift in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der für Naturforschung in cooperation with the Max Planck Society for the Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Advancement of Science under a Creative Commons Attribution Creative Commons Namensnennung 4.0 Lizenz. 4.0 International License. 232 M. Helfrich and W. Rüdiger • Metallopheophorbides as Substrates for Chlorophyll Synthetase extract was cleared by filtration and mixed with move the acetone, traces of acetic acid and excess dioxane (270 ml). Water was added slowly to this of Cu salt. Yield 2.3 jimol (51%) blue-green pig­ mixture at 0 °C until the absorption band of chlo­ ment, ?imax in CHC13 (relative absorption coeffi­ rophyll at 660 nm disappeared from the superna­ cients) = 400 (0.92), 424 (1.0), 507 (0.09), 656 tant (usually 800-900 ml H20 were needed). The (0.80) nm. TLC revealed 4 components with precipitate which consisted of mainly chlorophylls R f = 0.29, 0.33, 0.36 and 0.40. a + b was left in the suspension at 0 °C for 90 min. Ni complex: Pheophorbide a (4.5 jimol) was It was then removed by fast filtration at 0 °C with dissolved in 2 ml dimethylformamide and heated a precooled glass frit. The precipitate was dis­ under stirring with the saturated solution of solved in a few ml diethyl ether. A typical yield was NiCl2-6 H 20 in 1 ml dimethylformamide to 340 |imol chlorophyll a and 120 [imol chlorophyll 70-90 °C until no further spectral change oc­ b (61 % of the chlorophylls in the crude extract). curred (ca. 5 h). Workup with diethyl ether/water The preparation of pheophorbide a (1) was per­ as usual yielded 2.0 |amol (44%) green pigment. formed according to Hynninen and Lötjönen [7]. A.max in CHCI3 (relative absorption coefficients) = The mixture of chlorophylls a + b (300 |xmol) was 395 (1.02), 421 (1.0), 653 (1.04) nm. TLC revealed dissolved in 500 ml ice-cold diethyl ether. Ice-cold 1 main product (—90%) with RF = 0.28 and 3 by­ 30% aqueous HC1 (148 ml) was added to the solu­ products with R F = 0.24, 0.43 and 0.51. tion. Within 1 h under occasional shaking, pheo­ Co complex: Pheophorbide a (4.5 ^imol) was dis­ phorbide a accumulated in the lower (HC1) phase solved in 2 ml dimethylformamide and heated to whereas pheophytin b remained in the upper di­ 60 °C under stirring. The saturated solution of ethyl ether phase. After separation of the phases, CoCl 2 • 6 H20 in 1 ml dimethylformamide was the diethyl ether phase was reextracted three times added and the mixture heated to 60 °C for further with 30% HC1 (40 ml each). The combined HC1 10 min. Workup with diethyl ether/water yielded phases were diluted in a separatory funnel with the 1.9 |imol (42%) green pigment. A,max in CHC1 3 (re­ same volume (ca. 350 ml) ice-water. Ice-cold di­ lative absorption coefficients) = 405 (1.0), 641 ethyl ether (350 ml) was added. The pH value was (0.56) nm. TLC revealed 4 products with RF = 0, increased by drop wise addition of ice-cold 25% 0.20, 0.25 and 0.31. aqueous N H 3 until all pheophorbide a was trans­ Zn complex: Pheophorbide a (52 |amol) was dis­ ferred into the diethyl ether phase. The pigment solved in 10 ml CH 2C12 and heated to 35 °C. The was reextracted into 16% aqueous HC1 and from saturated solution of Zn(OAc )2 • 2 H 20 in 3 ml this phase into fresh diethyl ether after dilution of methanol was added. The mixture was refluxed for the lower phase with ice-water. The diethyl ether 10 min, cooled and poured into diethyl ether. phase was then washed with water until it was Workup with diethyl ether/water yielded 51 nmol acid-free, and dried with Na2S04. The yield of (98%) green pigment. Xmax in CHC1 3 (relative ab­ pheophorbide a (1) was 174 jxmol (78%). Analysis sorption coefficients) = 427 (1.0), 571 (0.09), 613 by HPLC (on a reverse phase C-l 8 column with (0.17), 659 (0.76) nm. TLC revealed 3 products 70% acetone) revealed minor amounts of pheo­ with R F = 0.39, 0.45 and 0.53. phorbide b (less than 2%) as the only contamina­ The mixture was separated by column chroma­ tion. tography. Pure products were obtained from the first and the last fraction. The most polar fraction proved to be 132-hydroxy-zinc-pheophorbide a Preparation of metallopheophorbides a (3a). A.max in CHC13 (relative absorption coeffi­ Various methods were applied for preparation cients) = 428 (1.0), 570 (0.08), 613 (0.15), 660 of various metallopheophorbides. (0.78) nm. MS: m/z 670 (59%, M +), 653 (100%), Cu complex [see ref. 8]: Pheophorbide a 611 (33%, M+-COOCH3) for MZn. The unpolar (4.5 (imol) was dissolved in 3 ml glacial acetic acid fraction was zinc-pheophorbide a (3). A.max in CHC1 3 and refluxed with 2 g Cu(II)acetate. After evapo­ (relative absorption coefficients) = 427 (1.0), 567 ration of the solvent, the residue was dissolved in (0.08), 611 (0.16), 659 (0.80) nm. MS: m/z 654 acetone/diethyl ether. The diethyl ether phase was (100%, M +), 595 (18%, M + -C O O C H 3), 577 washed several times with water in order to re­ (18%) for 64Zn. M. Helfrich and W. Rüdiger • Metallopheophorbides as Substrates for Chlorophyll Synthetase 233 Mg-complex: a) according to Strell and Urumov ments was obtained. The excess of 2,6-di-/-butyl- [9]: Pheophorbide a (3 ^imol) was dissolved in 5 ml 4-methylphenol was extracted with hexane.
Load more

Recommended publications
  • Chlorophyll Biosynthesis
    Chlorophyll Biosynthesis: Various Chlorophyllides as Exogenous Substrates for Chlorophyll Synthetase Jürgen Benz and Wolfhart Rüdiger Botanisches Institut, Universität München, Menziger Str. 67, D-8000 München 19 Z. Naturforsch. 36 c, 51 -5 7 (1981); received October 10, 1980 Dedicated to Professor Dr. H. Merxmüller on the Occasion of His 60th Birthday Chlorophyllides a and b, Protochlorophyllide, Bacteriochlorophyllide a, 3-Acetyl-3-devinylchlo- rophyllide a, Pyrochlorophyllide a, Pheophorbide a The esterification of various chlorophyllides with geranylgeranyl diphosphate was investigated as catalyzed by the enzyme chlorophyll synthetase. The enzyme source was an etioplast membrane fraction from etiolated oat seedlings ( Avena sativa L.). The following chlorophyllides were prepared from the corresponding chlorophylls by the chlorophyllase reaction: chlorophyllide a (2) and b (4), bacteriochlorophyllide a (5), 3-acetyl-3-devinylchlorophyllide a (6), and pyro­ chlorophyllide a (7). The substrates were solubilized with cholate which reproducibly reduced the activity of chlorophyll synthetase by 40-50%. It was found that the following compounds were good substrates for chlorophyll synthetase: chlorophyllide a and b, 3-acetyl-3-devinylchloro- phyllide a, and pyrochlorophyllide a. Only a poor or no reaction was found with protochloro­ phyllide, pheophorbide a, and bacteriochlorophyllide. This difference of reactivity was not due to distribution differences of the substrates between solution and pelletable membrane fraction. Furthermore, no interference between good and poor substrate was detected. Structural features necessary for chlorophyll synthetase substrates were discussed. Introduction Therefore no exogenous 2 was applied. The only substrate was 2 formed by photoconversion of endo­ The last steps of chlorophyll a (Chi a) biosynthe­ genous Protochlide (1) in the etioplast membrane.
    [Show full text]
  • Antibacterial Photosensitization Through Activation of PNAS PLUS Coproporphyrinogen Oxidase
    Antibacterial photosensitization through activation of PNAS PLUS coproporphyrinogen oxidase Matthew C. Surdela, Dennis J. Horvath Jr.a, Lisa J. Lojeka, Audra R. Fullena, Jocelyn Simpsona, Brendan F. Dutterb,c, Kenneth J. Sallenga, Jeremy B. Fordd, J. Logan Jenkinsd, Raju Nagarajane, Pedro L. Teixeiraf, Matthew Albertollec,g, Ivelin S. Georgieva,e,h, E. Duco Jansend, Gary A. Sulikowskib,c, D. Borden Lacya,d, Harry A. Daileyi,j,k, and Eric P. Skaara,1 aDepartment of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232; bDepartment of Chemistry, Vanderbilt University, Nashville, TN 37232; cVanderbilt Institute for Chemical Biology, Nashville, TN 37232; dDepartment of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232; eVanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN 37232; fBiomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN 37203; gDepartment of Biochemistry, Vanderbilt University, Nashville, TN 37232; hDepartment of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN 37232; iBiomedical and Health Sciences Institute, University of Georgia, Athens, GA 30602; jDepartment of Microbiology, University of Georgia, Athens, GA 30602; and kDepartment of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602 Edited by Ferric C. Fang, University of Washington School of Medicine, Seattle, WA, and accepted by Editorial Board Member Carl F. Nathan June 26, 2017 (received for review January 10, 2017) Gram-positive bacteria cause the majority of skin and soft tissue Small-molecule VU0038882 (‘882) was previously identified in infections (SSTIs), resulting in the most common reason for clinic a screen for activators of the S. aureus heme-sensing system two- visits in the United States.
    [Show full text]
  • Phyllobilins – the Abundant Bilin-Type Tetrapyrrolic Catabolites Of
    Chemical Society Reviews Phyllobilins – the Abundant Bilin -Type Tetrapyrrolic Catabolites of the Green Plant Pigment Chlorophyll Journal: Chemical Society Reviews Manuscript ID: CS-TRV-02-2014-000079.R1 Article Type: Tutorial Review Date Submitted by the Author: 02-May-2014 Complete List of Authors: Krautler, Bernhard; University of Innsbruck, Institute of Organic Chemistry Page 1 of 30 Chemical Society Reviews Phyllobilins-TutRev-BKräutler 2-May-14 1 Phyllobilins – the Abundant Bilin-type Tetrapyrrolic Catabolites of the Green Plant Pigment Chlorophyll Bernhard Kräutler Institute of Organic Chemistry and Centre of Molecular Biosciences, University of Innsbruck, Innrain 80/82, A-6020 Innsbruck, Austria E-mail: [email protected] Abstract . The seasonal disappearance of the green plant pigment chlorophyll in the leaves of deciduous trees has long been a fascinating biological puzzle. In the course of the last two and a half decades, important aspects of the previously enigmatic breakdown of chlorophyll in higher plants were elucidated. Crucial advances in this field were achieved by the discovery and structure elucidation of tetrapyrrolic chlorophyll catabolites, as well as by complementary biochemical and plant biological studies. Phyllobilins, tetrapyrrolic, bilin-type chlorophyll degradation products, are abundant chlorophyll catabolites, which occur in fall leaves and in ripe fruit. This tutorial review outlines ‘how’ chlorophyll is degraded in higher plants, and gives suggestions as to ‘why’ the plants dispose of their valuable green pigments during senescence and ripening. Insights into chlorophyll breakdown help satisfy basic human curiosity and enlighten school teaching. They contribute to fundamental questions in plant biology and may have practical consequences in agriculture and horticulture.
    [Show full text]
  • Uva-DARE (Digital Academic Repository)
    UvA-DARE (Digital Academic Repository) Pharmacological and physiological functions of polyspecific drug transporters Jonker, J.W. Publication date 2003 Link to publication Citation for published version (APA): Jonker, J. W. (2003). Pharmacological and physiological functions of polyspecific drug transporters. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:01 Oct 2021 Chapterr 4 Thee breast cancer resistance protein protects against a major chlorophyll-derivedd dietary phototoxin andd protoporphyria Johann W. Jonker, Marije Buitelaar, Els Wagenaar, Martin A. van der Valk, Georgee L. Scheffer, Rik J. Scheper, Torsten Plösch, Folkert Kuipers, Ronaldd P.J. Oude Elferink, Hilde Rosing, Jos H. Beijnen and Alfred H. Schinkel Proc.Proc. Natl. Acad. Set. USA (2002) 99: 15649-J5654 BCRPBCRP protects against a dietary phototo.xin Thee breast cancer resistance protein protects against aa major chlorophyll-derived dietary phototoxin andd protoporphyria Johann W.
    [Show full text]
  • Three Thioredoxin Targets in the Inner Envelope Membrane of Chloroplasts Function in Protein Import and Chlorophyll Metabolism
    Three thioredoxin targets in the inner envelope membrane of chloroplasts function in protein import and chlorophyll metabolism Sandra Bartsch*, Julie Monnet†, Kristina Selbach†, Franc¸oise Quigley†, John Gray‡, Diter von Wettstein§¶, Steffen Reinbothe†, and Christiane Reinbothe*†¶ *Lehrstuhl fu¨r Pflanzenphysiologie, Universita¨t Bayreuth, Universita¨tsstrasse 30, D-95447 Bayreuth, Germany; †Unite´Mixte de Recherche 5575, Centre d’Etudes et de Recherches sur les Macromole´cules Organiques, Universite´Joseph Fourier et Centre National de la Recherche Scientifique, BP53, F-38041 Grenoble Cedex 9, France; ‡Department of Biological Sciences, University of Toledo, 2801 West Bancroft Street, Toledo, OH 43606; and §Department of Crop and Soil Sciences and School of Molecular Biosciences, Washington State University, Pullman WA 99164-6420 Contributed by Diter von Wettstein, January 16, 2008 (sent for review December 11, 2007) Thioredoxins (Trxs) are ubiquitous small proteins with a redox- of Trxs in dark/light regulation of protein translocation and active disulfide bridge. In their reduced form, they constitute very chlorophyll (Chl) metabolism and provoke a scenario of deter- efficient protein disulfide oxidoreductases. In chloroplasts, two rence to pigment-sensitized oxidative stress in chloroplasts. types of Trxs (f and m) coexist and play central roles in the regulation of the Calvin cycle and other processes. Here, we Results identified a class of Trx targets in the inner plastid envelope Affinity Purification of Plastid Envelope Proteins Interacting with Trx membrane of chloroplasts that share a CxxC motif Ϸ73 aa from f and Trx m. Chloroplast Trxs contain two neighboring Cys their carboxyl-terminal end. Members of this group belong to a residues in a conserved motif, Trp-Cys-Gly-Pro-Cys (in some superfamily of Rieske iron–sulfur proteins involved in protein cases Trp-Cys-Pro-Pro-Cys), that is referred to as the Trx translocation and chlorophyll metabolism.
    [Show full text]
  • Photosensitizer Hydrogels For
    Synthesis and Characterization of Temperature- sensitive and Chemically Cross-linked Poly(N- isopropylacrylamide)/Photosensitizer Hydrogels for Applications in Photodynamic Therapy Simin Belali,†‡ Huguette Savoie,§ Jessica M. O’Brien† Atillio A. Cafolla, Barry O’Connell,┴ Ali Reza Karimi,‡ Ross W. Boyle,§* and Mathias O Senge†#* † School of Chemistry, SFI Tetrapyrrole Laboratory, Trinity Biomedical Science Institute, Trinity College Dublin, the University of Dublin, 152-160 Pearse Street, Dublin 2, Ireland. ‡ Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran. § Department of Chemistry, University of Hull, Cottingham Road, Kingston-upon-Hull, HU6 7RX, United Kingdom. School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland. ┴ Nano Research Facility, Dublin City University, Glasnevin, Dublin 9, Ireland. # Medicinal Chemistry, Trinity Translational Medicine Institute, Trinity Centre for Health Sciences, Trinity College Dublin, the University of Dublin, St. James’s Hospital, Dublin 8, Ireland. 1 KEYWORDS. Protoporphyrin IX – Hydrogels – Photodynamic therapy – Poly(N- isopropylacrylamide) – Photosensitizer – Pheophorbide a. ABSTRACT. A novel poly(N-isopropylacrylamide) (PNIPAM) hydrogel containing different photosensitizers (protoporphyrin IX (PpIX), pheophorbide a (Pba) and protoporphyrin IX dimethyl ester (PpIX-DME)) has been synthesized with a significant improvement in water- solubility and potential for PDT applications compared to the individual photosensitizers (PSs). Conjugation of PpIX, Pba and PpIX-DME to the poly(N-isopropylacrylamide) chain was achieved using the dispersion polymerization method. This study describes how the use of nanohydrogel structures to deliver a photosensitizer with low water-solubility and high aggregation tendencies in polar solvents overcomes these limitations. FT-IR spectroscopy, UV- Visible spectroscopy, 1H NMR, fluorescence spectroscopy, SEM and DLS analysis were used to characterize the PNIPAM-photosensitizer nanohydrogels.
    [Show full text]
  • Nomenclature of Tetrapyrroles
    Pure & Appi. Chem. Vol.51, pp.2251—2304. 0033-4545/79/1101—2251 $02.00/0 Pergamon Press Ltd. 1979. Printed in Great Britain. PROVISIONAL INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY and INTERNATIONAL UNION OF BIOCHEMISTRY JOINT COMMISSION ON BIOCHEMICAL NOMENCLATURE*t NOMENCLATURE OF TETRAPYRROLES (Recommendations, 1978) Prepared for publication by J. E. MERRITT and K. L. LOENING Comments on these proposals should be sent within 8 months of publication to the Secretary of the Commission: Dr. H. B. F. DIXON, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK. Comments from the viewpoint of languages other than English are encouraged. These may have special significance regarding the eventual publication in various countries of translations of the nomenclature finally approved by IUPAC-IUB. PROVISIONAL IUPAC—ITJB Joint Commission on Biochemical Nomenclature (JCBN), NOMENCLATUREOF TETRAPYRROLES (Recommendations 1978) CONTENTS Preface 2253 Introduction 2254 TP—O General considerations 2256 TP—l Fundamental Porphyrin Systems 1.1 Porphyrin ring system 1.2 Numbering 2257 1.3 Additional fused rings 1.4 Skeletal replacement 2258 1.5 Skeletal replacement of nitrogen atoms 2259 1.6Fused porphyrin replacement analogs 2260 1.7Systematic names for substituted porphyrins 2261 TP—2 Trivial names and locants for certain substituted porphyrins 2263 2.1 Trivial names and locants 2.2 Roman numeral type notation 2265 TP—3 Semisystematic porphyrin names 2266 3.1 Semisystematic names in substituted porphyrins 3.2 Subtractive nomenclature 2269 3.3 Combinations of substitutive and subtractive operations 3.4 Additional ring formation 2270 3.5 Skeletal replacement of substituted porphyrins 2271 TP—4 Reduced porphyrins including chlorins 4.1 Unsubstituted reduced porphyrins 4.2 Substituted reduced porphyrins.
    [Show full text]
  • "Bilin Metabolism in Plants: Structure, Function and Haem Oxygenase
    k Bilin Metabolism in Advanced article Article Contents Plants: Structure, • Introduction • Biosynthesis of Bilins Function and Haem • Phytochromobilin (PB) • Phycocyanobilin (PCB) Oxygenase Regulation of • Phycoerythrobilin (PEB) • Phycourobilin (PUB) Bilin Biosynthesis • HO Regulation in Bilin Biosynthesis • Biochemistry of Bilins Gyan Singh Shekhawat, Plant Biotechnology and Molecular Biology Labora- • Physiological Role of Bilins in Photosynthetic Organisms tory, Department of Botany, JNV University, Jodhpur, Rajasthan, India • Transcription Factors Involved in Bilin Signalling Suman Parihar, Plant Biotechnology and Molecular Biology Laboratory, Depart- • Phyllobilins – An Overlooked Class of Naturally Occurring Linear Tetrapyrroles ment of Botany, JNV University, Jodhpur, Rajasthan, India • Phyllobilins vs Bilins Lovely Mahawar, Plant Biotechnology and Molecular Biology Laboratory, • Conclusion and Future Prospects Department of Botany, JNV University, Jodhpur, Rajasthan, India Online posting date: 17th April 2019 Khushboo Khator, Plant Biotechnology and Molecular Biology Laboratory, Department of Botany, JNV University, Jodhpur, Rajasthan, India Neha Bulchandani, Plant Biotechnology and Molecular Biology Laboratory, Department of Botany, JNV University, Jodhpur, Rajasthan, India Bilins are open-chain tetrapyrroles with a wide structure and functions of bilins, this article k range of visible and nearly visible-light absorption also aims to recapitulate and discuss the current k and emission properties. The linear tetrapyr- progress in the field of bilins and to emphasise the role molecules function as chromophores of emerging areas. the light-harvesting phycobiliproteins and phytochrome-mediated light sensing in pho- tosynthetic organisms. They are derived from Introduction the cyclic precursor haem. The initial step in bilin biosynthesis is the conversion of haem into Bilins (bilichrome) are open-chain tetrapyrroles extensively dis- biliverdin (BV IX ) catalysed by haem oxygenase, tributed in all organisms excluding Archaea.
    [Show full text]
  • BINDING of PHEOPHORBIDE-A METHYL ESTER to NUCLEIC ACIDS of DIFFERENT SECONDARY STRUCTURES: a SPECTROSCOPIC STUDY
    BINDING OF PHEOPHORBIDE-a METHYL ESTER TO NUCLEIC ACIDS OF DIFFERENT SECONDARY STRUCTURES: A SPECTROSCOPIC STUDY О.А. Ryazanova 1, V.N. Zozulya 1, I.М. Voloshin 1, L.V. Dubey 2, I.Ya. Dubey 2 1Department of Molecular Biophysics, B. Verkin Institute for Low Temperature Physics and Engineering of NAS of Ukraine, 47 Nauky ave., 61103, Kharkiv, e-mail: [email protected] 2Department of Synthetic Bioregulators, Institute of Molecular Biology and Genetics of NAS of Ukraine, 150 Zabolotnogo str., 03680 Kyiv, Ukraine Binding of neutral Pheophorbide-a methyl ester (MePheo-a) to various synthetic polynucleotides, double-stranded poly(A)poly(U), poly(G)poly(C) and four-stranded poly(G), as well as to calf thymus DNA, was studied using the methods of absorption and polarized fluorescent spectroscopy. Measurements were performed in aqueous buffered solutions (pH 6.9) of low ionic strength (2 мM Na+) in a wide range of molar phosphate-to- dye ratios (P/D). Absorption and fluorescent characteristics of complexes formed between the dye and biopolymers were determined. Binding of MePheo-a to four-stranded poly(G) is shown to be accompanied by the most significant spectral transformations: hypochromism of dye absorption, large bathochromic shift of Soret absorption band (~26 nm) and fluorescence band (~9 nm) maxima, 48-fold enhancement of the dye emission intensity. In contrast, its binding to the double-stranded polynucleotides and native DNA induces only small shifts of absorption and fluorescence bands, as well as no more than 4-fold rise of fluorescence intensity. Substantial spectral changes and high value of fluorescence polarization degree (0.26) observed upon binding of MePheo-a to quadruplex poly(G) allow us to suggest the intercalation of the dye chromophore between guanine tetrads.
    [Show full text]
  • Design, Synthesis, and Characterization of Porphyrin
    Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2013 Design, synthesis, and characterization of porphyrin derivatives for biological applications Raja Gabadage Waruna Eranga Jinadasa Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Chemistry Commons Recommended Citation Jinadasa, Raja Gabadage Waruna Eranga, "Design, synthesis, and characterization of porphyrin derivatives for biological applications" (2013). LSU Doctoral Dissertations. 1482. https://digitalcommons.lsu.edu/gradschool_dissertations/1482 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. DESIGN, SYNTHESIS, AND CHARACTERIZATION OF PORPHYRIN DERIVATIVES FOR BIOLOGICAL APPLICATIONS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by R. G. Waruna Jinadasa B.Sc., University of Colombo, 2006 December 2013 Dedicated with love to my parents And my wife and son ii ACKNOWLEDGEMENTS First and foremost I offer my sincerest gratitude to my doctoral mentor, Professor Kevin M. Smith, who has supported me throughout my Ph.D study with his patience and unsurpassed knowledge whilst allowing me the room to work in my own way. I could not have imagined having a better advisor and mentor for my Ph.D studies. I also want give my sincere appreciations to Professor M.
    [Show full text]
  • Various Metallopheophorbides As Substrates for Chlorophyll Synthetase
    Various Metallopheophorbides as Substrates for Chlorophyll Synthetase Michael Helfrich and Wolfhart Rüdiger Botanisches Institut, Universität München, Menzinger Straße 67, D-W-8000 München 19 Z. Naturforsch. 47c, 231-238 (1992); received January 29, 1992 Chlorophyllide, Zincpheophorbide a, Copperpheophorbide a, Cobaltpheophorbide a, Nickel- pheophorbide a Pheophorbide a was prepared from a mixture of chlorophylls a and b by differential extrac­ tion with HC1 and saponification. The insertion of the following metal ions was investigated: Mg, Zn, Co, Cu, Ni. In the enzyme test with chlorophyll synthetase, the metallopheophorbides fall into two categories: the Mg- and Zn-complexes are good substrates, the Co-, Cu- and Ni-complexes are neither substrates nor competitive inhibitors for the enzyme reaction. This corresponds to two categories of complex structures: Mg- and Zn-porphyrins prefer penta- coordinate square-pyramidal structures, Co-, Cu- and Ni-porphyrins prefer tetracoordinate square-planar structures. A model for substrate binding to chlorophyll synthetase is proposed. Introduction Since chemical reactions of chlorophyllides, e.g. The last step of chlorophyll biosynthesis is the modifications of the side chains, result easily in a prenylation of chlorophyllide with either geranyl- loss of the central magnesium, we investigated the geranyl diphosphate or phytyl diphosphate [1]. insertion of several metal ions into pheophorbide a The activity of chlorophyll synthetase - the en­ and the possible acceptance of the resulting metal zyme
    [Show full text]
  • Pheophorbide A, a Chlorophyll Catabolite May Regulate Jasmonate Signalling During Dark-Induced Senescence in Arabidopsis
    bioRxiv preprint doi: https://doi.org/10.1101/486886; this version posted December 4, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Pheophorbide a, a chlorophyll catabolite may regulate jasmonate 2 signalling during dark-induced senescence in Arabidopsis 3 4 Sylvain Aubrya1, Niklaus Fankhauserb, Serguei Ovinnikova, Krzysztof Zienkiewiczc,d, 5 Ivo Feussnerc,d,e, Stefan Hörtensteinera1 6 7 aInstitute of Plant and Microbial Biology, University of Zürich, Zollikerstrasse 107, 8 8008 Zürich, Switzerland 9 bDepartment for Clinical Research, Clinical Trials Unit, University of Bern, 10 Finkenhubelweg 11, 3012 Bern, Switzerland 11 cDepartment of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, 12 University of Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany 13 dGöttingen Metabolomics and Lipidomics Laboratory, Göttingen Center for Molecular 14 Biosciences (GZMB), University of Göttingen, Justus-von-Liebig-Weg 11, 37077 15 Göttingen, Germany 16 eDepartment of Plant Biochemistry, Göttingen Center for Molecular Biosciences 17 (GZMB), University of Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, 18 Germany 19 20 1corresponding authors 21 22 Summary: Transcriptome and metabolite profiles of key chlorophyll breakdown 23 mutants reveal complex interplay between speed of chlorophyll degradation and 24 jasmonic acid signalling 25 26 List of author contributions 27 S.A. and S.H. conceived the original research plans; S.A. and S.O. performed most 28 of the experiments; K.Z. and I.F. analyzed jasmonic acid metabolites; S.A. and N.F. 29 analyzed the data; S.A.
    [Show full text]