DOCSLIB.ORG

Investigating the Life-Cycle of Photosystem II Using Mass Spectrometry Daniel Avram Weisz Washington University in St

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Investigating the Life-Cycle of Photosystem II Using Mass Spectrometry Daniel Avram Weisz Washington University in St Washington University in St. Louis Washington University Open Scholarship Arts & Sciences Electronic Theses and Dissertations Arts & Sciences Winter 12-15-2016 Investigating the Life-cycle of Photosystem II Using Mass Spectrometry Daniel Avram Weisz Washington University in St. Louis Follow this and additional works at: https://openscholarship.wustl.edu/art_sci_etds Recommended Citation Weisz, Daniel Avram, "Investigating the Life-cycle of Photosystem II Using Mass Spectrometry" (2016). Arts & Sciences Electronic Theses and Dissertations. 1009. https://openscholarship.wustl.edu/art_sci_etds/1009 This Dissertation is brought to you for free and open access by the Arts & Sciences at Washington University Open Scholarship. It has been accepted for inclusion in Arts & Sciences Electronic Theses and Dissertations by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY Department of Chemistry Dissertation Examination Committee: Michael L. Gross, Co-chair Himadri B. Pakrasi, Co-chair Robert E. Blankenship Dewey Holten Joseph Jez Investigating the Life-cycle of Photosystem II Using Mass Spectrometry by Daniel Avram Weisz A dissertation presented to The Graduate School of Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy December, 2016 Saint Louis, Missouri © 2016, Daniel Weisz Table of Contents List of Figures………………………………………………………………………......................v List of Tables……………………………………………………………………………………viii Abbreviations……………………………………………………………………………………..ix Acknowledgements……………………………………………………………………………….xi Dedication……………………………………………………………………………………….xiv Abstract…………………………………………………………………………………………..xv Chapter 1: Introduction: The use of advanced mass spectrometry to dissect the life-cycle of Photosystem II……..………………………………………..……..….1 Summary………………………….……………………………………………….2 Introduction……………………………………….……………………………….2 Composition of PSII complexes…………………………………………………..7 MS-based methods to study the composition of PSII complexes………....7 PSII life-cycle application: Composition of subcomplexes……………...13 PSII life-cycle application: Identification of accessory proteins………...20 PSII life-cycle application: Identification of PTMs……………………...22 Dynamics: Quantitative or semi-quantitative changes in PSII proteins and PTMs……………………………………………………………………………..27 MS-based methods to study PSII dynamics……………………………...27 PSII life-cycle application: Measuring changes in phosphorylation levels……………………………………………………………………..32 PSII life-cycle application: Measuring changes in oxidation levels……..34 PSII life-cycle application: Measuring the temporal dynamics of life- cycle events using isotopic labeling……………………………………...35 Structure: Determining protein-protein interactions in PSII complexes…………37 MS-based methods to study PSII structure………………………………37 PSII life-cycle application: Cross-linking and footprinting to determine interactions among PSII subunits….……………………………………..40 This work………………………………………………………………………...47 References…..……………………………………………………………………51 ii Chapter 2: Structural analysis of Photosystem II: Mass spectrometry-based cross-linking study shows that the Psb28 protein binds to cytochrome b559…..72 Summary………………………………………………………………………....73 Introduction………………………………………………………………………74 Results……………………………………………………………………………76 Discussion………………………………………………………………………..84 Materials and Methods……………………………………………………..…….93 References…………………………………………………………………........100 Supplementary Results and Discussion…………………………………….…..106 Chapter 3: Oxidative modifications of PSII detected by mass spectrometry……….…….121 Summary………………………………………………………………………..122 Introduction……………………………………………………………………..122 Results and Discussion…………………………………………………………124 Materials and Methods……………………………………………………….…144 References………………………………………………………………………147 Chapter 4: Structural localization of PsbQ in Photosystem II using chemical cross-linking and mass spectrometry…...………………………………………149 Summary………………………………………………………………………..150 Introduction……………………………………………………………………..150 Results…………………………………………………………………………..152 Discussion………………………………………………………………………169 Materials and Methods………………………………………………………….178 References………………………………………………………………………183 Chapter 5: Conclusions, future directions, and additional work………………………......194 Summary and conclusions of this work………………………………………...195 Future directions for MS contributions to PSII life-cycle research…………….197 General conclusion…………………………….………………………………..199 Additional work: Preliminary characterization of a PSII complex lacking the RC subunits…………………………………………………………………201 iii Results and Discussion…………………………………………………201 Materials and Methods………………………………………………….204 References………………………………………………………………205 iv List of figures Chapter 1: Introduction: The use of advanced mass spectrometry to dissect the life-cycle of Photosystem II Figure 1 Publications that use MS for PSII research, 1979-2015……………...…………..4 Figure 2 A schematic of the PSII life-cycle……………………………...………………..14 Chapter 2: Structural analysis of Photosystem II: Mass spectrometry-based cross-linking study shows that the Psb28 protein binds to cytochrome b559 Figure 1 Screening of mutant strains for elevated Psb28 content, characterization of the ΔpsbO PSII monomer, and quantification of Psb28 content in ΔpsbO PSII………………………………………………………………………………77 Figure 2 Immunoblot comparing ΔpsbO-PSII before and after cross-linking with 50, 100, and 300 molar excess BS3:PSII…………..……………………..………79 Figure 3 Mass spectrometric data showing a cross-link between (A) Psb28-K8 and PsbE-S2 and (B) Psb28-K8 and PsbF-A2…………...…………..............……….82 Figure 4 Binding model of Psb28 to RC47 based on cross-linking results……...………...86 Figure 5 A schematic of the PSII assembly process………………..……………………..92 Figure S1 Distribution of linear (Euclidean) distances between C-α’s of cross-linked residues in ΔpsbO-PSII........................................................................................113 Figure S2 Mass spectrometric data showing a cross-link between Psb28-A2 and PsbF- A2…………………………………………………………………………….....114 Figure S3 Intact-mass spectra of PsbE, PsbF, and Psb28……….…………………………115 Figure S4 PsbE-Psb28 cross-link detected in His47 sample………………………………116 Figure S5 PsbF-Psb28 cross-link detected in His47 sample……………………………….117 Figure S6 Isotope-encoded PsbF-Psb28 cross-link detected in His47 sample….…………118 Figure S7 Top docked conformations of Psb28 to RC47……………….…………………119 Figure S8 Psb28 binding above the PSII cytosolic-surface cavity……………….………..120 Chapter 3: Oxidative modifications of PSII detected by mass spectrometry Figure 1 Examples of MS/MS spectra detected that identify oxidative modifications of PSII residues……………...…......……...……………………………………126 v Figure 2 Residues with oxidative modifications detected in this study………...………..134 Figure 3 Cytosolic-side oxidative modifications detected in this study………………….135 Figure 4 Lumen-side oxidized residues detected in this study………………...…………137 Figure 5 Comparison of the lumen-side oxidative modified residues with channels previously identified in PSII by computational studies……...…….….139 Figure 6 Comparison of lumen-side oxidized residues detected by Frankel et al. (2012) and the current study……………………………………...141 Chapter 4: Structural localization of PsbQ in Photosystem II using chemical cross-linking and mass spectrometry Figure 1 Phylogenetic tree showing evolutionary relationship between PsbQ protein sequences from selected cyanobacterial species……...……..…………..153 Figure 2 Native-gel and SDS-PAGE analysis of HT3-PSII and Q-His-PSII…………...………...154 Figure 3 Chemical cross-linking of PsbQ with other PSII subunits…………...………………….156 Figure 4 Product-ion (MS/MS) spectra obtained for cross-linked peptides……...……...………..158 Figure 5 Gel electrophoresis and immunoblot analysis of HT3-PSII, HT3-∆Q-PSII, and HT3-∆O-PSII…………...….…………………………………………………………….161 Figure 6 Isolation of two kinds of PSII complexes from the Q-His strain of Synechocystis 6803………...….…...…………………………………………….163 Figure 7 Polypeptide compositions of Complex 1 and Complex 2……………………….164 Figure 8 Two-dimensional Blue-Native-PAGE and immunoblot analysis of Complex 1 and Complex 2………………………………………………….………………...……..166 Figure 9 Relative quantification of the PsbQ protein in Complex 1 and Complex 2…………......168 Figure 10 Schematic model for the binding of PsbQ to the interface of dimeric PSII………..……170 Figure 11 A schematic model for PSII assembly and repair………………………………………..177 Figure S1 Phylogenetic tree showing evolutionary relationship between PsbQ sequences from different cyanobacterial species…………… …..….…………………...…………188 Figure S2 BS3-induced cross-links between PsbQ and PsbO determined by tandem LC-MS and a subsequent database search using MassMatrix…......…………………....189 Figure S3 Mass spectrometric data showing an intermolecular PsbQ-PsbQ cross-linked peptide...190 Figure S4 Structural and electrostatic-potential comparison of PsbO from Synechocystis 6803 and T. ulcanus……......……………………...…………………......191 Figure S5 EDC-induced cross-links between PsbQ and CP47 determined by tandem LC-MS/MS and a subsequent database search in MassMatrix…..……………..…...…..192 vi Figure S6 Distance between K96 and K120 in the Synechocystis 6803 PsbQ crystal structure…...193 Chapter 5: Conclusions, future directions, and additional work Figure 1 Glycerol gradient ultracentrifugation of purified PSII complexes reveals an unidentified subcomplex in the ΔpsbO-His47-PSII sample………….……........202
Load more

Recommended publications
  • Title Hydrogen Atom Formation from the Photodissociation of Water Ice at 193 Nm Author(S)
    Hydrogen atom formation from the photodissociation of water Title ice at 193 nm Yabushita, A; Hashikawa, Y; Ikeda, A; Kawasaki, M; Author(s) Tachikawa, H JOURNAL OF CHEMICAL PHYSICS (2004), 120(11): 5463- Citation 5468 Issue Date 2004-03-15 URL http://hdl.handle.net/2433/39757 Copyright 2004 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires Right prior permission of the author and the American Institute of Physics. Type Journal Article Textversion none; publisher Kyoto University JOURNAL OF CHEMICAL PHYSICS VOLUME 120, NUMBER 11 15 MARCH 2004 Hydrogen atom formation from the photodissociation of water ice at 193 nm Akihiro Yabushita, Yuichi Hashikawa, Atsushi Ikeda, and Masahiro Kawasaki Department of Molecular Engineering, and Graduate School of Global Environmental Studies, Kyoto University, Kyoto 615-8510, Japan Hiroto Tachikawa Department of Molecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan ͑Received 21 April 2003; accepted 27 August 2003͒ The TOF spectra of photofragment hydrogen atoms from the 193 nm photodissociation of amorphous ice at 90–140 K have been measured. The spectra consist of both a fast and a slow ϭ Ϯ components that are characterized by average translational energies of 2kBTtrans 0.39 0.04 eV (2300Ϯ200 K) and 0.02 eV (120Ϯ20 K), respectively. The incident laser power dependency of the hydrogen atom production suggests one-photon process. The electronic excitation energy of a branched cluster, (H2O)6ϩ1 , has been theoretically calculated, where (H2O)6ϩ1 is a (H2O)6 cyclic cluster attached by a water molecule with the hydrogen bond.
    [Show full text]
  • Arxiv:1106.3917V2 [Astro-Ph.IM] 9 Feb 2015
    van Dishoeck & Visser: Molecular Photodissociation 1 published as a chapter in Laboratory Astrochemistry From Molecules through Nanoparticles to Grains eds. S. Schlemmer, T. Giesen, H. Mutschke, and C. Jäger 2015, Weinheim: Wiley-VCH 4 Molecular photodissociation Ewine F. van Dishoeck1;2 & Ruud Visser3;4 1Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, the Netherlands 2Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany 3Department of Astronomy, University of Michigan, 1085 S. University Ave, Ann Arbor, MI 48109-1107, USA 4European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748, Garching, Germany 4.1 Introduction Photodissociation is the dominant process by which molecules are removed in any region exposed to intense ultraviolet (UV) radiation. Such clouds of gas and dust are indicated by astronomers with the generic title ‘photon-dominated region’, or PDR. Originally, the term PDR referred mostly to dense molecular clouds close to bright young stars such as found in the Orion nebula. There are many other regions in space, however, in which photodissociation plays a crucial role in the chemistry: this includes diffuse and translucent interstellar clouds, high velocity shocks, the surface layers of protoplanetary disks, and cometary and exoplanetary atmospheres. In the simplest case, a molecule ABC absorbs a UV photon, which promotes it in- to an excited electronic state, and subsequently dissociates to AB + C. In reality, the arXiv:1106.3917v2 [astro-ph.IM] 9 Feb 2015 situation is much more complex because there are many electronic states that can be excited, with only a fraction of the absorptions leading to dissociation. Also, there are many possible photodissociation products, each of which can be produced in dif- ferent electronic, vibrational and rotational states depending on the wavelength of the incident photons.
    [Show full text]
  • In Vivo H NMR Methods to Study Dynamics of Chloroplast Water and Thylakoid Membrane Lipids in Leaves and in Photosynthetic Microorganisms
    In vivo 1H NMR methods to study dynamics of chloroplast water and thylakoid membrane lipids in leaves and in photosynthetic microorganisms Shanthadevi Pagadala Thesis committee Promotor Prof. Dr H. Van Amerongen Professor of Biophysics Wageningen University & Research Co-promotor Dr H. Van As Associate professor, Laboratory of Biophysics Wageningen University & Research Other members Prof. Dr L. F. M. Marcelis, Wageningen University & Research Prof. Dr J. A. Killian, Utrecht University, The Netherlands Dr C. P. M. Van Mierlo, Wageningen University & Research Dr A. Pandit, Leiden University, The Netherlands This research was conducted under the auspices of the Graduate School Experimental Plant Sciences. 1 In vivo H NMR methods to study dynamics of chloroplast water and thylakoid membrane lipids in leaves and in photosynthetic microorganisms Shanthadevi Pagadala Thesis submitted in fulfilment of the requirements for the degree of doctor at Wageningen University by the authority of the Rector Magnificus Prof. Dr. A. P. J. Mol, in the presence of the Thesis Committee appointed by the Academic Board to be defended in public on Tuesday 6 June 2017 at 11.00 a.m. in the Aula. Shanthadevi Pagadala In vivo 1H NMR methods to study dynamics of chloroplast water and thylakoid membrane lipids in leaves and in photosynthetic microorganisms 130 pages. PhD thesis, Wageningen University, Wageningen, NL (2017) With references, with summary in English ISBN: 978-94-6343-156-9 DOI: 10.18174/411095 Contents 1. Introduction 1 2. Chloroplast water in leaves as viewed by 1H DOSY and 13 DRCOSY NMR 3. The effect of dehydration on leaf cellular compartments 45 in relation to the water buffering role of subepidermal cells studied by 1H DOSY 4.
    [Show full text]
  • You Light up My Life
    Chapter 7: Photosynthesis Electromagnetic Spectrum Shortest Gamma rays wavelength X-rays UV radiation Visible light Infrared radiation Microwaves Longest Radio waves wavelength Photons • Packets of light energy • Each type of photon has fixed amount of energy • Photons having most energy travel as shortest wavelength (blue-violet light) Visible Light shortest range of most radiation range of heat escaping longest wavelengths reaching Earth’s surface from Earth’s surface wavelengths (most energetic) (lowest energy) gamma x ultraviolet near-infrared infrared microwaves radio rays rays radiation radiation radiation waves VISIBLE LIGHT 400 450 500 550 600 650 700 Wavelengths of light (nanometers) • Wavelengths humans perceive as different colors • Violet (380 nm) to red (750 nm) • Longer wavelengths, lower energy Fig. 7-2, p.108 Pigments • Colors you can see are the wavelengths not absorbed • These light catching particles capture energy from the various wavelengths. Variety of Pigments Chlorophylls a and b Carotenoids - orange Anthocyanins - purple/red Phycobilins - red Xanthophylls - yellow Chlorophylls chlorophyll a chlorophyll b Wavelength absorption (%) absorption Wavelength Wavelength (nanometers) Accessory Pigments Carotenoids, Phycobilins, Anthocyanins beta-carotene phycoerythrin (a phycobilin) percent of wavelengths absorbed wavelengths (nanometers) Pigments Fig. 7-3a, p.109 Pigments Fig. 7-3b, p.109 Pigments Fig. 7-3c, p.109 Pigments Fig. 7-3d, p.109 http://www.youtube.com/watch?v=fwGcOg PB10o&feature=fvsr Fig. 7-3e, p.109 Pigments Fig. 7-3e, p.109 Pigments in Photosynthesis • Bacteria – Pigments in plasma membranes • Plants – Pigments and proteins organized in chloroplast membranes T.E. Englemann’s Experiment Background • Certain bacterial cells will move toward places where oxygen concentration is high • Photosynthesis produces oxygen T.E.
    [Show full text]
  • SCHELVIS CV Profile 2010
    Curriculum vitae: Johannes Schelvis 09/7/2010 PERSONAL INFORMATION Johannes P. M. Schelvis, Associate Professor Montclair State University Department of Chemistry and Biochemistry 1 Normal Avenue Montclair, NJ 07043 EDUCATION B.S., Physics, 1985, Free University, Amsterdam, Netherlands Ph.D., Biophysics, 1995, University of Leiden, Leiden, Netherlands PROFESSIONAL EXPERIENCE Associate Professor Montclair State University September 2007 – present Assistant Professor New York University September 2000 – August 2007 Postdoctoral Researcher Michigan State University March 1995 - August 2000 HONORS AND AWARDS • Institute Fellow, Margaret and Herman Sokol Institute for the Pharmaceutical Life Sciences at Montclair State University, September 2008 - present • Goddard Fellowship, New York University, 2004 • Whitehead Fellowship for Junior Faculty in Biomedical or Biological Sciences, New York University, 2003. GRANTS AWARDED ACTIVE • "Molecular Mechanisms of Photolyase and Cryptochrome" National Science Foundation, MCB-0920013, August 2009 – July 2012 , $419,453 t.c. (PI) • "Binding of ICER to Its Own Promoter as a Mode of Cooperative Regulation" Margaret and Herman Sokol Institute for Pharmaceutical Life Sciences, September 2008 – August 2011 (1-year no cost extension), $100,000 (PI with Dr. Carlos Molina) • "Light-Driven Damage and Repair of DNA", Faculty Scholarship Program, Montclair State University, 2008 – 2012 , 6 TCH (PI) COMPLETED • "Fingerprinting DNA Damage" Margaret and Herman Sokol Faculty/Student Research Grant Program, July 2008
    [Show full text]
  • Genetically Engineered Mutant of the Cyanobacterium Synechocystis
    Proc. Natl. Acad. Sci. USA Vol. 83, pp. 9474-9477, December 1986 Botany Genetically engineered mutant of the cyanobacterium Synechocystis 6803 lacks the photosystem II chlorophyll-binding protein CP-47 (photosynthesis/cartridge mutagenesis/reaction center/chlorophyll fluorescence) WIM F. J. VERMAAS*t, JOHN G. K. WILLIAMS*, A. WILLIAM RUTHERFORDt, PAUL MATHISt, AND CHARLES J. ARNTZEN* *Central Research and Development Department, E. I. du Pont de Nemours and Co., Inc., Wilmington, DE 19898; and tCentre d'Etudes Nucleaires de Saclay, Departement de Biologie, Service de Biophysique, 91191 Gif-sur-Yvette Cedex, France Contributed by Charles J. Arntzen, August 29, 1986 ABSTRACT CP-47 is absent in a genetically engineered also be found in an analogous location in the D1 and D2 mutant of cyanobacterium Synechocystis 6803, in which the proteins. psbB gene [encoding the chlorophyll-binding photosystem U To obtain more information on the role of CP-47 (and (PSII) protein CP-47] was interrupted. Another chlorophyll- thereby possibly to localize P680), a well-defined mutant of binding PSI1 protein, CP-43, is present in the mutant, and the cyanobacterium Synechocystis 6803 was constructed. In functionally inactive PSII-enriched particles can be isolated this mutant (9) the only change was an interruption of the from mutant thylakoids. We interpret these data as indicating psbB gene (encoding CP-47) by a piece ofDNA containing the that the PSII core complex of the mutant still assembles in the gene for aminoglycoside-3'-phosphotransferase, conferring absence of CP-47. The mutant lacks a 77 K fluorescence kanamycin resistance. This mutant is no longer capable of emission maximum at 695 nm, suggesting that the PSII reaction PSII electron transport (9).
    [Show full text]
  • Oriented Chlorine Atoms As a Probe of the Nonadiabatic Photodissociation Dynamics of Molecular Chlorine Andrew J
    JOURNAL OF CHEMICAL PHYSICS VOLUME 113, NUMBER 20 22 NOVEMBER 2000 Oriented chlorine atoms as a probe of the nonadiabatic photodissociation dynamics of molecular chlorine Andrew J. Alexander,a) Zee Hwan Kim, S. Alex Kandel,b) and Richard N. Zarec) Department of Chemistry, Stanford University, Stanford, California 94305 T. Peter Rakitzis Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 711 10 Heraklion—Crete, Greece Yukako Asano and Satoshi Yabushita Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan ͑Received 27 June 2000; accepted 1 September 2000͒ Molecular chlorine was photolyzed using circularly polarized radiation at 310 and 330 nm, and 2 orientation moments of the chlorine-atom Cl( P j) photofragment distributions were measured by resonance enhanced multiphoton ionization using circularly polarized light with Doppler resolution. The product atoms were found to be strongly oriented in the laboratory as a result of both incoherent and coherent dissociation mechanisms, and the orientation moments contributed by each of these mechanisms have been separately measured. The experimental results can be explained by 1⌸ ⍀ϭ nonadiabatic transitions from the C 1u state to higher states of 1u symmetry, induced by radial derivative coupling. Ab initio calculations indicate strong Rosen–Zener–Demkov noncrossing-type radial derivative couplings between states of 1u symmetry. The observed angular ͑␤ ͒ 2 distribution parameter indicates that 88% of Cl*( P1/2) fragments produced at 310 nm originate from a perpendicular transition to the C state. The orientation measurements suggest that 67Ϯ16% 35 2 3⌺ϩ Ϯ 3⌬ of Cl*( P1/2) atoms dissociate via the 1u( 1u) state, and 21 6% dissociate via the 1u( 1u) state.
    [Show full text]
  • Photolysis of Diatomic Molecules As a Source of Atoms in Planetary Exospheres?
    A&A 633, A39 (2020) Astronomy https://doi.org/10.1051/0004-6361/201936230 & c ESO 2020 Astrophysics Photolysis of diatomic molecules as a source of atoms in planetary exospheres? R. R. Valiev1,2, A. A. Berezhnoy3, I. S. Gritsenko4, B. S. Merzlikin5, V. N. Cherepanov4, T. Kurten1, and C. Wöhler6 1 University of Helsinki, Department of Chemistry, PO Box 55, A.I. Virtanens Plats 1, 00014 Helsinki, Finland e-mail: [email protected] 2 Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, Lenin Avenue 30, Tomsk 634050, Russia 3 Sternberg Astronomical Institute, Moscow State University, 13, Universitetskij pr., 119234 Moscow, Russia 4 Tomsk State University, 36 Lenin Avenue, 634050 Tomsk, Russia 5 Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Avenue, 634050 Tomsk, Russia 6 Image Analysis Group, Technical University of Dortmund, Otto-Hahn-Str. 4, 44227 Dortmund, Germany Received 3 July 2019 / Accepted 24 July 2019 ABSTRACT We calculated the cross sections of photolysis of OH, LiO, NaO, KO, HCl, LiCl, NaCl, KCl, HF, LiF, NaF, and KF molecules using quantum chemistry methods. The maximal values for photolysis cross sections of alkali metal monoxides are on the order of 10−18 cm2. The lifetimes of photolysis for quiet Sun at 1 astronomical unit are estimated as 2:0 × 105, 28, 5, 14, 2:1 × 105, 225, 42, 52, 2 × 106, 35 400, 486, and 30 400 s for OH, LiO, NaO, KO, HCl, LiCl, NaCl, KCl, HF, LiF, NaF, and KF, respectively. We performed a comparison between values of photolysis lifetimes obtained in this work and in previous studies.
    [Show full text]
  • Studies of the Two Redox Active Tyrosines in Photosystem II
    Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1527 Studies of the two redox active tyrosines in Photosystem II NIGAR AHMADOVA ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6214 ISBN 978-91-554-9933-4 UPPSALA urn:nbn:se:uu:diva-320916 2017 Dissertation presented at Uppsala University to be publicly examined in Room 2001, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, Wednesday, 14 June 2017 at 13:15 for the degree of Doctor of Philosophy. The examination will be conducted in English. Faculty examiner: Professor Robert Burnap (Oklahoma State University, USA). Abstract Ahmadova, N. 2017. Studies of the two redox active tyrosines in Photosystem II. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1527. 72 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-9933-4. Photosystem II is a unique enzyme which catalyzes light induced water oxidation. This process is driven by highly oxidizing ensemble of four Chl molecules, PD1, PD2, ChlD1 and ChlD2 called, + - - P680. Excitation of one of the Chls in P680 leads to the primary charge separation, P680 Pheo . Pheo transfers electrons sequentially to the primary quinone acceptor QA and the secondary quinone + acceptor QB. P680 in turn extracts electrons from Mn4CaO5 cluster, a site for the water oxidation. There are two redox active tyrosines, TyrZ and TyrD, found in PSII. They are symmetrically located on the D1 and D2 central proteins. Only TyrZ acts as intermediate electron carrier between P680 and Mn4CaO5 cluster, while TyrD does not participate in the linear electron flow and stays oxidized under light conditions.
    [Show full text]
  • Nonresonant Photons Catalyze Photodissociation of Phenol Kallie I
    Article Cite This: J. Am. Chem. Soc. 2019, 141, 1067−1073 pubs.acs.org/JACS Nonresonant Photons Catalyze Photodissociation of Phenol Kallie I. Hilsabeck,†,§ Jana L. Meiser,†,§ Mahima Sneha,†,§ John A. Harrison,†,‡ and Richard N. Zare*,† † Department of Chemistry, Stanford University, Stanford, California 94305, United States ‡ Chemistry, Institute of Natural and Mathematical Sciences, Massey University Auckland, Auckland 0632, New Zealand *S Supporting Information ABSTRACT: Phenol represents an ideal polyatomic system for demonstrating photon catalysis because of its large polarizability, well-characterized excited-state potential energy surfaces, and nonadiabatic dissociation dynamics. A non- resonant IR pulse (1064 nm) supplies a strong electric field (4 × 107 V/cm) during the photolysis of isolated phenol (C6H5OH) molecules to yield C6H5O + H near two known energetic thresholds: the S1/S2 conical intersection and the S1 − S0 origin. H-atom speed distributions show marked changes in the relative contributions of dissociative pathways in both cases, compared to the absence of the nonresonant IR pulse. Results indicate that nonresonant photons lower the activation barrier for some pathways relative to others by dynamically Stark shifting the excited-state potential energy surfaces rather than aligning molecules in the strong electric field. Theoretical calculations offer support for the experimental interpretation. ■ INTRODUCTION Previously reported observations of photon catalysis are almost exclusively limited to diatomic molecular systems. A catalyst is a species that promotes a reaction but is not 1,2 consumed throughout the course of the reaction. Even for Stolow and co-workers used time-resolved, ultrafast spec- fi thermodynamically favorable reactions, catalysts are often troscopy to con rm that application of a strong, nonresonant fi necessary to achieve appreciable yields because of unfavorable infrared (IR) eld led to substantial changes in the relative kinetics.
    [Show full text]
  • The Photodissociation Wavelength of Ozone Is 320 Nm. This Means That Ozone Efficiently Absorbs Light Below This Wavelength
    The photodissociation wavelength of ozone is 320 nm. This means that ozone efficiently absorbs light below this wavelength and breaks apart according to the following photochemical reaction. O3 + h O2 + O Any excess energy above the dissociation energy will be carried away by the kinetic energy of O2 and O. Assuming that the kinetic energy is shared equally by O2 and O calculate the velocity of O2 and O when ozone is photodissociated by a photon with a wavelength of 250 nm. Solution: The photodissociation of a molecule can be treated conceptually in the same way that one treats an ionization process. The atom has a binding energy in the molecule. If the incident photon has a greater energy then the bond is broken and the atom can leave. Any excess energy is carried away as kinetic energy. The difference in the case of atoms is that the kinetic energy is not simple. For an electron we assume that the all of the kinetic energy is in the electron (because its mass is so small). For atoms and molecules we cannot assume that only one of the species will carry away all of the kinetic energy. This problem simplifies the matter by stating that the kinetic energy will be carried away by both species (O2 and O) equally. MKS units. The energy of a 250 nm photon is: E = hc/ = (6.626 x 10-34 Js)(2.99 x 108 m/s)/(250 x 10-9 m) = 7.92 x 10-19 J The energy of the O-O bond in ozone is: E = hc/ = (6.626 x 10-34 Js)(2.99 x 108 m/s)/(320 x 10-9 m) = 6.19 x 10-19 J Therefore the energy of a 250 nm photon is greater than the threshold needed to break a bond by: E = E(250 nm photon) – E(320 nm threshold energy) = 1.73 x 10-19 J This is the total kinetic energy of the photodissociated ozone molecule.
    [Show full text]
  • Evolution of Oxygenic Photosynthesis
    EA44CH24-Fischer ARI 17 May 2016 19:44 ANNUAL REVIEWS Further Click here to view this article's online features: • Download figures as PPT slides • Navigate linked references • Download citations Evolution of Oxygenic • Explore related articles • Search keywords Photosynthesis Woodward W. Fischer, James Hemp, and Jena E. Johnson Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125; email: wfi[email protected] Annu. Rev. Earth Planet. Sci. 2016. 44:647–83 Keywords First published online as a Review in Advance on Great Oxidation Event, photosystem II, chlorophyll, oxygen evolving May 11, 2016 complex, molecular evolution, Precambrian The Annual Review of Earth and Planetary Sciences is online at earth.annualreviews.org Abstract This article’s doi: The origin of oxygenic photosynthesis was the most important metabolic 10.1146/annurev-earth-060313-054810 innovation in Earth history. It allowed life to generate energy and reducing Copyright c 2016 by Annual Reviews. power directly from sunlight and water, freeing it from the limited resources All rights reserved of geochemically derived reductants. This greatly increased global primary productivity and restructured ecosystems. The release of O2 as an end prod- Access provided by California Institute of Technology on 07/14/16. For personal use only. Annu. Rev. Earth Planet. Sci. 2016.44:647-683. Downloaded from www.annualreviews.org uct of water oxidation led to the rise of oxygen, which dramatically altered the redox state of Earth’s atmosphere and oceans and permanently changed all major biogeochemical cycles. Furthermore, the biological availability of O2 allowed for the evolution of aerobic respiration and novel biosynthetic pathways, facilitating much of the richness we associate with modern biology, including complex multicellularity.
    [Show full text]