DOCSLIB.ORG

UC San Diego Electronic Theses and Dissertations

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
UC San Diego Electronic Theses and Dissertations UC San Diego UC San Diego Electronic Theses and Dissertations Title Vanadium-dependent bromoperoxidase in a marine Synechococcus / Permalink https://escholarship.org/uc/item/34x4t8rp Author Johnson, Todd Laurel Publication Date 2013 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO Vanadium-dependent bromoperoxidase in a marine Synechococcus A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Marine Biology by Todd L. Johnson Committee in charge: Brian Palenik, Chair Bianca Brahamsha, Co-Chair Lihini Aluwihare James Golden Jens Mühle Bradley Moore 2013 Copyright Todd L. Johnson, 2013 All rights reserved. The dissertation of Todd L. Johnson is approved, and it is acceptable in quality and form for publication on microfilm and electronically: ________________________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________ Co-Chair ________________________________________________________ Chair University of California, San Diego 2013 iii DEDICATION To Janet, Tim, and Andrew Johnson, for unconditional love and support. iv TABLE OF CONTENTS Signature Page……………………………………………………………………………iii Dedication ………………………………………………………………………………..iv Table of Contents………………………………………………………………………….v List of Abbreviations………………………………………………………………......…vi List of Figures………………………………………………………………………...…viii List of Tables…………………………………………………………..…………………xi Acknowledgements………………………………………….…………………….……xiii Vita……………………………………………………….………………………...……xiv Abstract…………………....……………………………………………………...…...…xv Chapter 1: Introduction………..………………………………………………….….……1 Chapter 2: Characterization of a functional vanadium-dependent bromoperoxidase in the marine cyanobacterium Synechococcus sp. CC9311 ..…………………………..………10 Chapter 3: Expression patterns of vanadium-dependent bromoperoxidase in Synechococcus sp. CC9311 as a response to physical agitation and a bacterial assemblage …………..………………………………………………………………………………..27 Chapter 4: Halomethane production by vanadium-dependent bromoperoxidase in marine Synechococcus………………………………………………………………………….107 Chapter 5: Conclusions………………..………………….………………….…………149 Appendix 1……………………………………………………………………………...154 v LIST OF ABBREVIATIONS VBPO – vanadium-dependent bromoperoxidase bp – base pair kDa – kilodalton °C – degrees Celsius DNA – deoxyribonucleic acid PCR – polymerase chain reaction MES - 2-(N-morpholino)ethanesulfonic acid Na3VO4 – sodium orthovanadate H2O2 – hydrogen peroxide hr - hour min – minute μmol - micromole μM - micromolar nM – nanomolar ppt – parts per trillion SDS-PAGE – sodium dodecyl sulfate - polyacrylamide gel electrophoresis Br- – bromide I- - iodide Cl- - chloride ppt – parts per trillion mTorr – millitorr VHOC – volatile halogenated organic compounds vi CH3Br – methyl bromide CH3I – methyl iodide CH3Cl – methyl chloride CH2Br2 - dibromomethane CH2Cl2 - dichloromethane CHBr3 - bromoform CHCl3 - chloroform vii LIST OF FIGURES Figure 1: SDS-PAGE gels of total proteins from Synechococcus strains WH8102, CC9311, and VBPO from Corallina officinialis (Co VBPO, Sigma) stained with Sypro Ruby (left) and with phenol red (right) for bromoperoxidase activity. The migrations of molecular mass standards are indicated on the left in kDa………………...…………….13 Figure 2: Amino acid alignment of VBPO from Synechococcus sp. strain CC9311 and strain WH8020. Active site is shown by the solid bar while vanadium-coordinating residues are shown in bold, as determined by homology to Ascophyllum nodosom. Arrows indicate residues used for the design of environmental probes ………………...14 Figure 3: Neighbor-joining tree of known bromoperoxidase sequences and related genes. Amino acid sequences obtained from NCBI using Synechococcus sp. strain CC9311 (YP_731869.1) in a BLASTp. Asterisk (*) indicates only node with less than 50% bootstrap support. Accession numbers are shown in Supplementary Table 1……..….…14 Figure 4: Neighbor-Joining tree of environmental VBPO sequences. Nucleotide sequences were trimmed to a conserved region of approximately 180-bp (alignment shown in Supplementary Figure 2). “Pier#” samples were obtained from a degenerate primer (PierF and PierR) clone library from the Scripps Pier in La Jolla, CA………..…15 Fig. S1: Alignment of the well-conserved region between cyanobacterial and eukaryotic algal vanadium-dependent bromoperoxidases (VBPOs) used to construct the phylogenetic tree shown in Figure 3. Sequences were obtained from the National Center for Biotechnology Information’s nr protein database……………………………………20 Fig. S2: Nucleotide alignment of the Scripps Pier clone library to metagenomic sequences (see “Materials and Methods”). This alignment was used for the neighbor- joining analysis and phylogenetic tree construction shown in Figure 4…………………23 Figure 3.1: A diagram of the insertional gene inactivation of VBPO (sync_2681) in Synechococcus CC9311 (shown in A) to form the VMUT genotype (shown in B). Steps: 1. PCR amplification of gene fragment, 2. Clone into TOPO vector to form pTOP2681, 3. Excise new fragment with EcoRI and cloned into pMUT100 form pVBR1, 4………....84 Figure 3.2: Mutant genotyping, a 1% agarose gel showing PCR products from boiling DNA extraction of stock cultures using A) RPOC1 primers (303 bp) and B) verifications primers (750 bp). Lanes left to right: 1 Kb Plus Ladder (bp); CC9311; VMUT; VMUT2; no DNA control…………………………………………………………………………..85 Figure 3.3: Mutant growth curves showing the cell counts (lines) comparing the growth of CC9311 and the original mutant, VMUT, under stirred and still conditions over the first three growth curves (A-C) as well as CC9311 and VMUT2 (D-F). VBPO specific activities (bars) are also shown comparing CC9311 to VMUT2 (D-F) over three……...86 viii Figure 3.4: VBPO specific activity of proteins harvested from cultures of A) CC9311 and B) VMUT2 at different phases of growth. VBPO activities of biological triplicates are shown from cultures grown under still conditions (white bars), cultures grown under still conditions and subjected to a short term (4 hr) period of stirring (grey bars), and ……..87 Figure 3.5: Genotype of VMUT after disappearance of stir-sensitive phenotype. PCR products from boiling DNA extraction shown on 1% agarose gels. Panel A: verifications primers (750 bp) lanes left to right: 1) 1 Kb Plus Ladder (bp); 2) CC9311; 3) VMUT stir; 4) VMUT still; 5) no DNA control. Panel B: RPOC1 primers (303 bp) ………………..88 Figure 3.6: Duplicate SDS-PAGE of proteins extracted from CC9311 and VMUT2 in stationary phase; grown still, still with only four hours of stirring, or constant stirring. Each lane was loaded with 55 μg protein and stained with A) sypro ruby or B) phenol-red in the presence of Na3VO4, KBr, and H2O2 for VBPO activity. Lanes left to right….....89 Figure 3.7: Induction and persistence of VBPO with stirring. A) Cell counts from cultures of CC9311 used to test the induction of VBPO with stirring over time. Vertical solid line shows when stirring was either initiated or halted in cultures. Growth rates of the cultures after the vertical line are 0.56 d-1 for the culture that was stirred from inoculation……..90 Figure 3.8: VBPO and cell resistance to hydrogen peroxide. Phycoerythrin autofluorescence of CC9311 and VMUT cultures after the addition of hydrogen peroxide. Solid lines represent cultures that have been preconditioned with stirring while dotted lines represent cultures that have been grown still from inoculation. Top left: Trial 1….91 Figure 3.9: VBPO specific activities of CC9311 cultures exposed to A) 25 μM hydrogen peroxide and b) 0.1 μM methyl viologen (MV)………………………………………....92 Figure 3.10: Cell counts of Acaryochloris marina cultures tested for VBPO activity (trial 2). ……………………………………………………………………………..…………93 Figure 3.11: Native PAGE Gel of Synechococcus sp. CC9311 and Acaryochloris marina proteins, 21 μg protein per lane, from still and stirred cultures. Gel in panel A was stained with Sypro Ruby for total proteins, Gel in panel B was stained with phenol red for VBPO activity. Lanes left to right A) 1. Benchmark Protein ladder; 2. CC9311, still……......…94 Figure 3.12: SDS-PAGE of Synechococcus CC9311 and Acaryochloris marina proteins, 26.5 μg protein per lane. Gel in panel A was stained with Sypro Ruby for total proteins, Gel in panel B was stained with phenol red for VBPO activity. Lanes left to right A) 1. Benchmark Protein ladder; 2. CC9311, still; 3. CC9311, stirred; 4. A. marina. …..……95 ix Figure 3.13: Neighbor-joining tree showing the 16S gene library constructed of the bacterial assemblage that induces VBPO in Synechococcus CC9311, the 19 isolates, as well known sequences. TJ# refers to a clone from the 16S rRNA gene library and PTB# refers to a strain isolated from the Pteridomonas enrichment. ………………….……....96 Figure 3.14: Alignment of the 421 bp fragment of the 16s rRNA genes from the PTB enrichment clone library (TJ#), 19 isolated strains (PTB#) and known sequences……...97 Figure 4.1: Experimental design used to measure halomethane production in Synechococcus cultures……………………………………………………………….. 140 Figure 4.2: Cell concentrations of cultures (1.5 L) used in the purge-and-trap experiment (solid lines days 2-7). Vertical solid line at day seven indicates when CC9311 (Black) and VMUT2 (light grey) cultures
Load more

Recommended publications
  • Methods and Compositions for the Treatment of Infection and Control of Flora Using Haloperoxidase
    Europaisches Patentamt 19 European Patent Office Office europeen des brevets © Publication number : 0 500 387 A2 12 EUROPEAN PATENT APPLICATION (2j) Application number : 92301448.4 6i) int. ci.5: A61K 37/50 (22) Date of filing : 21.02.92 (30) Priority: 21.02.91 US 660994 (72) Inventor : Allen, Robert Charles 3215 Woodcrest San Antonio, Texas 78209 (US) (43) Date of publication of application 26.08.92 Bulletin 92/35 @) Representative : Sheard, Andrew Gregory et al Kilburn & Strode 30, John Street @ Designated Contracting States : London WC1N 2DD (GB) AT BE CH DE DK ES FR GB GR IT LI LU MC NL PT SE © Applicant : EXOXEMIS, INC. 18585 Sigma Road, Suite 100 San Antonio, Texas 78209 (US) (54) Methods and compositions for the treatment of infection and control of flora using haloperoxidase. (57) Haloperoxidases are used to selectively bind to and, in the presence of peroxide and halide, inhibit the growth of target microbes without eliminating desirable microbes or significantly damaging other components, such as host cells, in the environment of the target microbe. When a target microbe, e.g., a pathogenic microbe, has a binding capacity for haloperoxidase greater than that of a desired microbe, e.g., members of the normal flora, the target microbe selectively binds the haloperoxidase with little or no binding of the haloperoxidase by the desired microbe. In the presence of peroxide and halide, the target bound haloperoxidase catalyzes halide oxidation and facilitates the disproportionation of peroxide to singlet molecular oxygen at the surface of the target microbe. The lifetime of singlet molecular oxygen restricts damage to the surface resulting in selective killing of the target microbe with a minimum of collateral damage to the desired microbe or physiological medium.
    [Show full text]
  • Haloperoxidase Mediated Quorum Quenching by Nitzschia Cf Pellucida: Study of the Metabolization of N-Acyl Homoserine Lactones by a Benthic Diatom
    Mar. Drugs 2014, 12, 352-367; doi:10.3390/md12010352 OPEN ACCESS marine drugs ISSN 1660-3397 www.mdpi.com/journal/marinedrugs Article Haloperoxidase Mediated Quorum Quenching by Nitzschia cf pellucida: Study of the Metabolization of N-Acyl Homoserine Lactones by a Benthic Diatom Michail Syrpas 1, Ewout Ruysbergh 1, Lander Blommaert 2, Bart Vanelslander 2, Koen Sabbe 2, Wim Vyverman 2,*, Norbert De Kimpe 1 and Sven Mangelinckx 1,* 1 Department of Sustainable Organic Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent B-9000, Belgium; E-Mails: [email protected] (M.S.); [email protected] (E.R.); [email protected] (N.D.K.) 2 Laboratory of Protistology and Aquatic Ecology, Department of Biology, Ghent University, Krijgslaan 281-S8, Ghent B-9000, Belgium; E-Mails: [email protected] (L.B.); [email protected] (B.V.); [email protected] (K.S.) * Authors to whom correspondence should be addressed; E-Mails: [email protected] (S.M.); [email protected] (W.V.); Tel.: +32-(0)9-264-59-51 (S.M.); Fax: +32-(0)9-264-62-21 (S.M.); Tel.: +32-(0)9-264-85-01 (W.V.); Fax: +32-(0)9-264-85-99 (W.V.). Received: 5 November 2013; in revised form: 16 December 2013 / Accepted: 23 December 2013 / Published: 17 January 2014 Abstract: Diatoms are known to produce a variety of halogenated compounds, which were recently shown to have a role in allelopathic interactions between competing species. The production of these compounds is linked to haloperoxidase activity.
    [Show full text]
  • Bacterialdye-Decolorizingperoxidases
    DE GRUYTER Physical Sciences Reviews. 2016; 20160051 Chao Chen / Tao Li Bacterial dye-decolorizing peroxidases: Biochemical properties and biotechnological opportunities DOI: 10.1515/psr-2016-0051 1 Introduction In biorefineries, processing biomass begins with separating lignin fromcellulose and hemicellulose. Thelatter two are depolymerized to give monosaccharides (e.g. glucose and xylose), which can be converted to fuels or chemicals. In contrast, lignin presents a challenging target for further processing due to its inherent heterogene- ity and recalcitrance. Therefore it has only been used in low-value applications. For example, lignin is burnt to recover energy in cellulosic ethanol production. Valorization of lignin is critical for biorefineries as it may generate high revenue. Lignin is the obvious candidate to provide renewable aromatic chemicals [1, 2]. As long as it can be depolymerized, the phenylpropane units can be converted into useful phenolic chemicals, which are currently derived from fossil fuels. In nature, lignin is efficiently depolymerized by rot fungi that secrete heme- and copper-containing oxidative enzymes [3]. Although lignin valorization is an important objective, industrial depolymerization by fungal enzymes would be difficult, largely due to difficulties in protein expression and genetic manipulation infungi. In recent years, however, there is a growing interest in identifying ligninolytic bacteria that contain lignin- degrading enzymes. So far, several bacteria have been characterized to be lignin degraders [4, 5]. These bacteria, including actinobacteria and proteobacteria, have a unique class of dye-decolorizing peroxidases (DyPs, EC 1.11.1.19, PF04261) [6, 7]. These enzymes are equivalent to the fungal oxidases in lignin degradation, but they are much easier to manipulate as their functional expression does not involve post translational modification.
    [Show full text]
  • An Antioxidant Nanozyme That Uncovers the Cytoprotective Potential of Vanadia Nanowires
    ARTICLE Received 22 Oct 2013 | Accepted 18 Sep 2014 | Published 21 Nov 2014 DOI: 10.1038/ncomms6301 An antioxidant nanozyme that uncovers the cytoprotective potential of vanadia nanowires Amit A. Vernekar1,*, Devanjan Sinha2,*, Shubhi Srivastava2, Prasath U. Paramasivam1, Patrick D’Silva2 & Govindasamy Mugesh1 Nanomaterials with enzyme-like properties has attracted significant interest, although limited information is available on their biological activities in cells. Here we show that V2O5 nanowires (Vn) functionally mimic the antioxidant enzyme glutathione peroxidase by using cellular glutathione. Although bulk V2O5 is known to be toxic to the cells, the property is altered when converted into a nanomaterial form. The Vn nanozymes readily internalize into mammalian cells of multiple origin (kidney, neuronal, prostate, cervical) and exhibit robust enzyme-like activity by scavenging the reactive oxygen species when challenged against intrinsic and extrinsic oxidative stress. The Vn nanozymes fully restore the redox balance without perturbing the cellular antioxidant defense, thus providing an important cytoprotection for biomolecules against harmful oxidative damage. Based on our findings, we envision that biocompatible Vn nanowires can provide future therapeutic potential to prevent ageing, cardiac disorders and several neurological conditions, including Parkinson’s and Alzheimer’s disease. 1 Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. 2 Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India. * These authors contributed equally to this work. Correspondence and requests for materials should be addressed to P.D. (email: [email protected]) or to G.M. (email: [email protected]). NATURE COMMUNICATIONS | 5:5301 | DOI: 10.1038/ncomms6301 | www.nature.com/naturecommunications 1 & 2014 Macmillan Publishers Limited.
    [Show full text]
  • Downloaded from Genbank
    Methylotrophs and Methylotroph Populations for Chloromethane Degradation Françoise Bringel1*, Ludovic Besaury2, Pierre Amato3, Eileen Kröber4, Stefen Kolb4, Frank Keppler5,6, Stéphane Vuilleumier1 and Thierry Nadalig1 1Université de Strasbourg UMR 7156 UNISTR CNRS, Molecular Genetics, Genomics, Microbiology (GMGM), Strasbourg, France. 2Université de Reims Champagne-Ardenne, Chaire AFERE, INR, FARE UMR A614, Reims, France. 3 Université Clermont Auvergne, CNRS, SIGMA Clermont, ICCF, Clermont-Ferrand, France. 4Microbial Biogeochemistry, Research Area Landscape Functioning – Leibniz Centre for Agricultural Landscape Research – ZALF, Müncheberg, Germany. 5Institute of Earth Sciences, Heidelberg University, Heidelberg, Germany. 6Heidelberg Center for the Environment HCE, Heidelberg University, Heidelberg, Germany. *Correspondence: [email protected] htps://doi.org/10.21775/cimb.033.149 Abstract characterized ‘chloromethane utilization’ (cmu) Chloromethane is a halogenated volatile organic pathway, so far. Tis pathway may not be representa- compound, produced in large quantities by terres- tive of chloromethane-utilizing populations in the trial vegetation. Afer its release to the troposphere environment as cmu genes are rare in metagenomes. and transport to the stratosphere, its photolysis con- Recently, combined ‘omics’ biological approaches tributes to the degradation of stratospheric ozone. A with chloromethane carbon and hydrogen stable beter knowledge of chloromethane sources (pro- isotope fractionation measurements in microcosms, duction) and sinks (degradation) is a prerequisite indicated that microorganisms in soils and the phyl- to estimate its atmospheric budget in the context of losphere (plant aerial parts) represent major sinks global warming. Te degradation of chloromethane of chloromethane in contrast to more recently by methylotrophic communities in terrestrial envi- recognized microbe-inhabited environments, such ronments is a major underestimated chloromethane as clouds.
    [Show full text]
  • Halogenation Enzymes in Bacteria Associated with the Red-Banded Acorn Worm, Ptychodera Jamaicensis" (2011)
    San Jose State University SJSU ScholarWorks Master's Theses Master's Theses and Graduate Research Fall 2011 Halogenation Enzymes in Bacteria Associated with the Red- banded Acorn Worm, Ptychodera jamaicensis Milena May Lilles San Jose State University Follow this and additional works at: https://scholarworks.sjsu.edu/etd_theses Recommended Citation Lilles, Milena May, "Halogenation Enzymes in Bacteria Associated with the Red-banded Acorn Worm, Ptychodera jamaicensis" (2011). Master's Theses. 4099. DOI: https://doi.org/10.31979/etd.snbx-gv6x https://scholarworks.sjsu.edu/etd_theses/4099 This Thesis is brought to you for free and open access by the Master's Theses and Graduate Research at SJSU ScholarWorks. It has been accepted for inclusion in Master's Theses by an authorized administrator of SJSU ScholarWorks. For more information, please contact [email protected]. HALOGENATION ENZYMES IN BACTERIA ASSOCIATED WITH THE RED- BANDED ACORN WORM, PTYCHODERA JAMAICENSIS A Thesis Presented to The Faculty of the Department of Biology San José State University In Partial Fulfillment of the Requirements for the Degree Master of Science by Milena M. Lilles December 2011 © 2011 Milena M. Lilles ALL RIGHTS RESERVED The Designated Thesis Committee Approves the Thesis Titled HALOGENATION ENZYMES IN BACTERIA ASSOCIATED WITH THE RED- BANDED ACORN WORM, PTYCHODERA JAMAICENSIS by Milena M. Lilles APPROVED FOR THE DEPARTMENT OF BIOLOGY SAN JOSÉ STATE UNIVERSITY December 2011 Dr. Sabine Rech Department of Biology Dr. Brandon White Department of Biology Dr. Roy Okuda Department of Chemistry ABSTRACT HALOGENATION ENZYMES IN BACTERIA ASSOCIATED WITH THE RED- BANDED ACORN WORM, PTYCHODERA JAMAICENSIS by Milena M. Lilles Organohalogens have diverse biological functions in the environment.
    [Show full text]
  • LABORATORY EVOLUTION of CYTOCHROME P450 PEROXYGENASE ACTIVITY Thesis by Patrick C. Cirino in Partial Fulfillment of the Requirem
    LABORATORY EVOLUTION OF CYTOCHROME P450 PEROXYGENASE ACTIVITY Thesis by Patrick C. Cirino In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 2004 (Defended June 2, 2003) ii © 2004 Patrick C. Cirino All Rights Reserved iii ACKNOWLEDGEMENTS My tenure at Caltech has been a wonderful and rewarding experience. I leave this chapter of my life feeling enlightened because of what I have learned, and charmed because of the people that I have had the fortune to spend time with. I am forever indebted to these people for their contributions to my scientific and personal growth over the years. I wish to thank my advisor Frances Arnold. I thank her for having confidence in me and for giving me the opportunity to work in her lab. I thank her for her constant encouragement, support, and guidance. She has been incredibly patient and has given me the time to grow professionally and mature personally. My respect and admiration for Frances continues to grow, and she has become a source of inspiration as I begin my own academic career. I could not have had a better advisor and I will never be able to thank her enough for all that she has given me. I wish to acknowledge the entire Division of Chemistry and Chemical Engineering for their resources, their courses, and for providing such a supportive and inspiring work environment. In particular, the following faculty members have been extremely helpful: I thank Dave Tirrell for all his generosity. As Division Chair, Dave has provided invaluable services which I have been able to take advantage of.
    [Show full text]
  • The Crystal Structure of the C45S Mutant of Annelid Arenicola Marina
    JOBNAME: PROSCI 17#4 2008 PAGE: 1 OUTPUT: Wednesday March 5 15:35:56 2008 csh/PROSCI/152302/ps0733993 The crystal structure of the C45S mutant of annelid Arenicola marina peroxiredoxin 6 supports its assignment to the mechanistically typical 2-Cys subfamily without any formation of toroid-shaped decamers AUDE SMEETS,1 ELE´ ONORE LOUMAYE,2 ANDRE´ CLIPPE,2 JEAN-FRANCxOIS REES,2 2 1 BERNARD KNOOPS, AND JEAN-PAUL DECLERCQ 1Unit of Structural Chemistry (CSTR), Universite´ catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium 2Laboratory of Cell Biology, Institut des Sciences de la Vie, Universite´ catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium (RECEIVED December 10, 2007; FINAL REVISION January 24, 2008; ACCEPTED January 28, 2008) Abstract The peroxiredoxins (PRDXs) define a superfamily of thiol-dependent peroxidases able to reduce hydrogen peroxide, alkyl hydroperoxides, and peroxynitrite. Besides their cytoprotective antioxidant function, PRDXs have been implicated in redox signaling and chaperone activity, the latter depending on the formation of decameric high-molecular-weight structures. PRDXs have been mechanistically divided into three major subfamilies, namely typical 2-Cys, atypical 2-Cys, and 1-Cys PRDXs, based on the number and position of cysteines involved in the catalysis. We report the structure of the C45S mutant of annelid worm Arenicola marina PRDX6 in three different crystal forms determined at 1.6, 2.0, and 2.4 A˚ resolution. Although A. marina PRDX6 was cloned during the search of annelid homo- logs of mammalian 1-Cys PRDX6s, the crystal structures support its assignment to the mechanistically typical 2-Cys PRDX subfamily.
    [Show full text]
  • Haloperoxidase Zur Behandlung Von Infektionen Und Kontrolle Der Flora
    Title (en) Haloperoxidase for the treatment of infection and control of flora Title (de) Haloperoxidase zur Behandlung von Infektionen und Kontrolle der Flora Title (fr) Haloperoxidase pour le traitement des infections et le contrôle de la flore Publication EP 0923939 B1 20070620 (EN) Application EP 98122809 A 19920221 Priority • EP 92301448 A 19920221 • US 66099491 A 19910221 Abstract (en) [origin: EP0500387A2] Haloperoxidases are used to selectively bind to and, in the presence of peroxide and halide, inhibit the growth of target microbes without eliminating desirable microbes or significantly damaging other components, such as host cells, in the environment of the target microbe. When a target microbe, e.g., a pathogenic microbe, has a binding capacity for haloperoxidase greater than that of a desired microbe, e.g., members of the normal flora, the target microbe selectively binds the haloperoxidase with little or no binding of the haloperoxidase by the desired microbe. In the presence of peroxide and halide, the target bound haloperoxidase catalyzes halide oxidation and facilitates the disproportionation of peroxide to singlet molecular oxygen at the surface of the target microbe. The lifetime of singlet molecular oxygen restricts damage to the surface resulting in selective killing of the target microbe with a minimum of collateral damage to the desired microbe or physiological medium. The methods and compositions of the invention are highly useful in the therapeutic or prophylactic antiseptic treatment of human or animal subjects, since their use can be designed to be highly effective in combatting bacterial or fungal infections without significant damage to normal flora or host cells.
    [Show full text]
  • Marine Haloperoxidases
    chem. Rev. 1998, 93, 1937-1944 Marine Haloperoxidases Alison Butler’ and J. V. Walker oepemnmt of ~%~II/SIIY. (~vasllyof cawom$. anta &&am. CaBlanh, 93106 Reodved A@ 20, 1993 (Revlsed Manusmt Racslved May 20, 1993) Contents I. Introduction 1937 A. Halogenated Compounds in the Marine 1937 Envlronment p: ? E. Marine Habperoxidases 1938 6 1. Types of Marine Haioperoxidases 1938 8. 2. Standard Assay of Habperoxidase 1939 Activity 11. Vanadium Bromoperoxidase 1939 A. Characterlstics of V-ErPO 1939 1. Isoiatlon and Purlflcation of VgrpO 1939 2. The Vanadium Sne 1939 .... .. ...:.;.. .. E. Reactivity Of V-ErpO 1940 . :. .. :. [.. 1. Halogenation and HalldeAssisted 1940 AII~~utler received her &A. from Reed College in 1977 and her Disproportionation of Hydrogen P~.D.from the University of California. San Diego. in 1962. Alter Peroxide pwMoaaal stays at UC Los Angeles and Caitech. she joked the 2. Specific Activltles 1941 faculty at UC Santa Barbara in 1986. She is a recent reciplent of an American Cancer Society. Junior Faculty Research Award, 1941 3. Enzyme Kinetics an Alfred P. Sbn Foundatlon Fellowship, and the UCSE PIOUS 4. Peroxide Selectivity 1941 TeacherlSchoiar Award. Her research interestsarein bioinaganic 5. Mechanistic Considerations 1941 chemistry and metalloblochemistry. including that of the marlne environment. C. Stability of V-ErPO 1942 D. Comment on the Putative Non-i-bma Iron 1942 Eromoperoxidases 111. Fell“ Bromoperoxidase 1942 A. Characteristics of FeHeme 1942 Eromoperoxbse E. Reactivity of FeHeme Bromoperoxidase 1942 1. Biosynthetic Investigations 1943 2. Other FeHema Haloperoxidases 1943 1V. Future Directions 1944 I. Introductlon A. Halogenated Compounds in the Msrlne Environment Jenylalne Vanessa Walker was born in St.
    [Show full text]
  • Master Thesis the Haloperoxidase-DABCO System
    UNIVERSITY OF COPENH AGEN FACULTY OF SCIENCE Master Thesis Valentin Waschulin The Haloperoxidase-DABCO System Exploring a Novel Method of Enzymatic Pulp Bleaching Name of department: Department of Geosciences and Natural Resource Management, Forest, Nature and Biomass Author: Valentin Waschulin Title / Subtitle: The Haloperoxidase-DABCO System: Exploring a Novel Method of Enzymatic Pulp Bleaching Academic advisor: Prof. Claus Felby Industrial advisors: Pedro Loureiro Submitted: 18. September 2016 2/79 Acknowledgements I want to express my thanks to Prof. Claus Felby for the opportunity of performing my Master Thesis at his chair, and Henrik Lund for providing me with the possibility of performing the thesis work at the Technical Industries department at Novozymes A/S, Denmark. I want to thank Pedro Loureiro for providing supervision, detailed expertise and great scientific discussions throughout the time of the thesis. I also want to thank all the scientists and associates at the department for discussion, advice and hands-on help in the laboratory; in particular Owik Herold-Majumdar for guidance and discussion concerning the model compound work. Finally, I want to thank my parents Susanne and Georg and my sister Laura for supporting me throughout my studies in Denmark. 3/79 Abstract A novel approach for cellulosic pulp bleaching and hexenuronic acid (HexA) removal using a haloperoxidase (Hap) and a tertiary amine catalyst (DABCO) was tested on oxygen-delignified eucalypt kraft pulp. In a buffered system (pH 4,5, 60°C), high brightness gain, good response to peroxide-reinforced alkaline extraction and more than 80% HexA removal were achieved, while preserving cellulose integrity. In an optimized, but non-buffered system, Hap/DABCO was compared to the non-enzymatic HOCl treatment and an inferior performance of the former was found.
    [Show full text]
  • Download (1364Kb)
    Short-Lived Trace Gases in the Surface Ocean and the Atmosphere 1 Peter S. Liss, Christa A. Marandino, Elizabeth E. Dahl, Detlev Helmig, Eric J. Hintsa, Claire Hughes, Martin T. Johnson, Robert M. Moore, John M.C. Plane, Birgit Quack, Hanwant B. Singh, Jacqueline Stefels, Roland von Glasow, and Jonathan Williams Abstract The two-way exchange of trace gases between the ocean and the atmosphere is important for both the chemistry and physics of the atmosphere and the biogeochemistry of the oceans, including the global cycling of elements. Here we review these exchanges and their importance for a range of gases whose lifetimes are generally short compared to the main greenhouse gases and which are, in most cases, more reactive than them. Gases considered include sulphur and related compounds, organohalogens, non-methane hydrocarbons, ozone, ammonia and related compounds, hydrogen and carbon monoxide. Finally, we stress the interactivity of the system, the importance of process understanding for modeling, the need for more extensive field measurements and their better seasonal coverage, the importance of inter-calibration exercises and finally the need to show the importance of air-sea exchanges for global cycling and how the field fits into the broader context of Earth System Science. 1.1 Introduction trace gas cycling between the oceanic and atmospheric reservoirs. Despite their seemingly low abundances, short-lived In this chapter we present current knowledge on trace gases in the atmosphere critically influence surface ocean cycling processes, atmospheric reactivity global climate change, stratospheric ozone chemistry, and importance, and the influence of air-sea exchange and the oxidative capacity of the atmosphere.
    [Show full text]