DOCSLIB.ORG

Study Ofan Oxygenated Heme Complex in Frozen Solution

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Study Ofan Oxygenated Heme Complex in Frozen Solution Proc. Nat. Acad. Sci. USA Vol. 69, No. 9, pp. 2396-2399, September 1972 Study of an Oxygenated Heme Complex in Frozen Solution by Mossbauer Emission Spectroscopy (oxygen binding/hemoglobin/Co(II)-protoporphyrin IX) LINDA MARCHANT*, MICHAEL SHARROCKt, BRIAN M. HOFFMAN*, AND ECKARD MtfNCKt * Department of Chemistry, Northwestern University, Evanston, Illinois 60201; and t Department of Physics, University of Illinois, Urbana, Ill. 61801 Communicated by I. C. Gunsalus, May 31, 1972 ABSTRACT We have used Mossbauer emission spectros- copy to study an oxygenated heme complex, produced in a N N frozen solution by nuclear decay from the isomorphous 57Co-labeled compound. The Missbauer parameters agree with those obtained by Mossbauer absorption spectros- copy of oxyhemoglobin. Thus, a nonprotein environment Co- 57Fe for iron can duplicate the unique oxyhemoglobin Moss- IV bauer spectrum. The electronic structure of the heme iron \ HEME,// 0 in oxyhemoglobin is not significantly influenced by the rn PLANE 02 protein environment. Miissbauer emission spectroscopy can be useful in the investigation of heme proteins. FIG. 1. Formation of 57Fe-labeled oxyheme-(OMe)2(C6H5N) by nuclear decay of 57Co in oxyCoP-(OMe)2(C5HsN). One aim of the study of hemoproteins is to learn the mecha- nisms by which an apoprotein can modify the chemical re- activity and the electronic structure of the heme prosthetic MOSSBAUER EMISSION SPECTROSCOPY group. Recent studies of oxygen binding to cobalt proto- Observation of the Mbssbauer effect can provide information porphyrin, both in solution and incorporated into an apopro- about the chemical environment of the 57Fe nucleus by either tein, have achieved a partial understanding of the influences emission or absorption spectroscopy. Both techniques re- of a protein on oxygen binding. Like the heme group in hemo- quire the same basic experimental arrangement: a source globin and myoglobin, five-coordinate complexes of the heme containing 57Co, an absorber containing 57Fe, and a means analog Co(II)-protoporphyrin IX dimethyl ester [CoP- of counting radiation transmitted through the absorber. (OMe)2], in solution can bind molecular oxygen (1, 2). When As shown in Fig. 2a, 57Co decays by electron capture to 57Fe, Co(II)-protoporphyrinIX (CoP) is incorporated into apohemo- populating an excited state (T11, = 0.1 Msec) of the iron globin or apomyoglobin, it has a greater affinity for oxygen nucleus. The 14.4-keV 7y-radiation emitted in the subsequent and a greater resistance to oxidation than free [CoP-(OMe)2]T de-excitation process can resonantly excite 5"Fe nuclei in (1, 3, 4). The electronic structures, however, of CoP and the absorber. In the absorption technique, the source emits its oxygen adduct in a protein environment do not differ a monochromatic y-radiation, and the hyperfine energies significantly from those of CoP-(OMe)2 and its oxygen adduct of the nuclear levels of 57Fe in the absorber are measured in free solution, as evidenced by optical absorption and elec- (Fig. 2b). Emission spectroscopy, on the other hand, uses a tron paramagnetic resonance (EPR) measurements (1). single line absorber to investigate the energy levels of the Such comparisons for the naturally occuring heme group have 57Fe nuclei produced by decay of 57Co in the source (Fig. 2c). previously been impossible since heme cannot ordinarily Information can thus be gained regarding the iron complex be prepared in a five-coordinate state and heme in solution that exists during times of order 0.1 usec after electron cap- is oxidized to hemin upon exposure to oxygen. ture (12, 13). We have used Mdssbauer emission spectroscopy to study Although the absorption technique has received more an oxygenated heme complex, produced in frozen solution attention, M6ssbauer emission spectroscopy can offer distinct by nuclear decay from the isomorphous 57Co-labeledd com- advantages for certain biological studies. It requires far less pound (Fig. 1). Our results are compared with those obtained material than the absorption method if cobalt of high specific from Mbssbauer absorption spectroscopy of oxyhemoglobin.§ activity is used. (Less than 1 nmol of 57Co can be sufficient.) We find no evidence that the iron-oxygen linkage in oxy- Moreover, it provides the unique opportunity of investigating hemoglobin is influenced by the stereochemical constraints some iron compounds that cannot be made by direct chemical imposed by the protein. methods. The emission spectra of their cobalt analogs can convey information about the desired iron compounds. Prep- Abbreviations: heme, Fe(II)-protoporphyrin IX; CoP, Co(II)- aration of a suitable 57Co complex does not assure, however, protoporphyrin IX; heme-(OMe)2, dimethyl ester of heme; CoP- that the desired iron compound can be studied, because the (OMe)2 dimethyl ester of CoP; EPR, electron paramagnetic reso- nance; oxy-, indicates complex with molecular oxygen. § The Mossbauer spectra of oxyhemoglobin are not well under- t Although CoP and heme are the prosthetic groups in the pro- stood in terms of electronic structure. Several theories have been teins, our solution studies used the more soluble CoP-(OMe)2 and advanced to account for the diamagnetism of the heme complex heme-(OMe)2. Esterification of the propionic acid groups of a me- (5-7) and the temperature dependence of the quadrupole splitting talloprotoporphyrin IX does not significantly influence the por- (8, 9). No model has been conclusively proven correct, although phyrin ring. recent evidence appears to favor an Fe(III)-02- complex (10, 11). 2396 Downloaded by guest on September 25, 2021 Proc. Nat. Acad. Sci. USA 69 (1972) Oxygenated Heme in Solution 2397 SOURCE ABSORBER 57Co (270 d) SOURCE ABSORBER ELECTRON r CAPTURE r- 136 s 14.4 keV i_ 57Fe ABSORPTION SPECTROSCOPY EMISSION SPECTROSCOPY (a) (b) (c) FIG. 2. (a) Decay scheme of "7Co, showing only those transitions relevant to Mossbauer spectroscopy. (b) Schematic representation of Mossbauer absorption spectroscopy, showing emission of photons in the source and resonant absorption in the absorber. The quadrupole splitting of the 14.4-keV excited nuclear level in the absorber is measured. The isomer shift is not considered in the figure. (c) Schematic representation of Mossbauer emission spectroscopy. The quadrupole splitting of the excited nuclear level in the source is measured. electron shell must rearrange in the aftermath of the nuclear purchased from New England Nuclear in the form of CoCl2 decay process. This rearrangement process leads to ejection in acidified solution (Lot 7712, 33 mCi/ml). All other chem- of Auger electrons, and highly charged positive iron ions icals were Fisher reagent grade. Cobalt chloride was dried can occur. The resulting Coulombic forces may disrupt the under vacuum and redissolved in dimethylformamide (10 chemical bonds and fragment the molecule. However, 57Co mCi/ml). Pyridine was distilled from KOH, and toluene from complexes involving large conjugated ring structures resist CaH2, before use. Dimethylformamide was treated with disruption. In cobalt phthalocyanine and vitamin B12 com- KOH and CaO and then vacuum-distilled. 57Co-enriched pounds there is no evidence for fragmentation and well-de- CoP-(OMe)2 (100 Ci/mol) was prepared by a modification fined spectra are observed (14, 15). Recently, 57Co-labeled of the method of Adler (18). Co(II) pyridine complexes have been studied by M6ssbauer A solution of CoP-(O0Me)2(C5H5N)2 was prepared by addition emission spectroscopy, and the results are in good agreement of 0.2 ml degassed pyridine to CoP-(OMe)2 and further degas- with those obtained by absorption studies of the correspond- sing the solution by the freeze-thaw method. An EPR spectrum ing Fe(IJ) compounds (16, 17). We have extended these in- showed that no other paramagnetic cobalt species was vestigations to the porphyrin system by comparing the pa- present, and, in particular, that there was no oxyCoP-(ONle)r2 rameters of heme-(OMe)2(C5H5N)2 obtained from Mossbauer (C5H5N). The CoP-(OMe)2(C5H5N)2 solution was syringed into absorption and emission spectroscopy. a nylon M6ssbauer sample cell (0.5-inch diameter) under a nitrogen atmosphere. EXPERIMENTAL OxyCoP-(OMe)2(C5H5N) was prepared from the bispyridine Materials complexI. The filled M6ssbauer sample cell was placed in a Protoporphyrin IX dimethyl ester, Grade 1, was purchased Schlenk tube that was in contact with a dry ice-acetone bath. from Sigma and used without further purification. 57Co was Oxygen was passed through the tube for 1 hr while the solu- tion was agitated mildly. The Schlenk tube was then immersed in liquid nitrogen, and the cell containing the frozen sample was transferred rapidly to the M6ssbauer cryostat. Before the M6ssbauer experiment, EPR measurements 0 showed that the material labeled with 57CoP-(OMe)2(C5H5N)2 could be completely and reversibly oxygenated. However, complete oxygenation was not achieved in the 1Idssbauer F (a) cell. This is believed to be due to the differences in the oxy- genation and freezing processes caused by differences in sam- ple volume and sample containers. I Methods 0~ A constant-acceleration Mossbauer spectrometer was used C') (19). The M6ssbauer source, the 57Co-labeled porphyrin com- m pound, was mounted in the tail section of a Janis variable- temperature cryostat. The y-rays could pass horizontally through i\Iylar windows. The drive unit was mounted out- side the cryostat. The drive rod terminated in a ring through which a Xe-CO2 proportional counter was positioned. A ABSORBER VELOCITY IN mm/sec K4Fe(CN)6 3H20 absorber (0.12 mg 57Fe/cm2) was mounted FIG. 3. (a) Mossbauer emission spectrum of CoP-(OMe)2- on the ring in front of the counter window. The temperature (C5H5N)2 at 4.2OK. The solid line is the result of fitting two doub- of the source could be stabilized anywhere between 4.20K lets to the data by the method of least squares. (b) Mossbauer and room temperature.
Load more

Recommended publications
  • Evidence for the Role of Endogenous Carbon Monoxide in Memory Processing
    Evidence for the Role of Endogenous Carbon Monoxide in Memory Processing M. C. Cutajar and T. M. Edwards Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/19/4/557/1816404/jocn.2007.19.4.557.pdf by guest on 18 May 2021 Abstract & For a decade and a half, nitric oxide (NO) has been impli- number of electrophysiological investigations have concluded cated in memory processing across a wide variety of tasks and that endogenous CO is involved in long-term potentiation. species. Comparatively, endogenously produced carbon mon- Although not evidence for a role in memory per se, these oxide (CO) has lagged behind as a target for research into the studies did point to the possible importance of CO in mem- pharmacological processes underlying memory formation. This ory processing. In addition, there is now evidence to suggest is surprising given that CO is formed in memory-associated that endogenous CO is important in avoidance learning and brain regions, is structurally similar to NO, and along with possible for other tasks. This review therefore seeks to pro- NO can activate guanylate cyclase, which is an enzyme well mote endogenous CO as a potentially important target for characterized in memory processing. Nevertheless, a limited memory research. & INTRODUCTION important in memory processing (Kemenes, Kemenes, Carbon monoxide (CO) is traditionally thought of as Andrew, Benjamin, & O’Shea, 2002; Izquierdo et al., an air pollutant. Indeed, inhalation of environmental 2000; Bernabeu et al., 1997; Kendrick et al., 1997). By CO in sufficient quantities may lead to intoxication detailing the evidence for CO production in the hippo- through the production of carbonmonoxyhemoglobin, campus, its role in synaptic plasticity and those few which results in decreased oxygen storage and trans- behavioral studies implicating CO in memory consoli- port in the bloodstream.
    [Show full text]
  • Magnesium-Protoporphyrin Chelatase of Rhodobacter
    Proc. Natl. Acad. Sci. USA Vol. 92, pp. 1941-1944, March 1995 Biochemistry Magnesium-protoporphyrin chelatase of Rhodobacter sphaeroides: Reconstitution of activity by combining the products of the bchH, -I, and -D genes expressed in Escherichia coli (protoporphyrin IX/tetrapyrrole/chlorophyll/bacteriochlorophyll/photosynthesis) LUCIEN C. D. GIBSON*, ROBERT D. WILLOWSt, C. GAMINI KANNANGARAt, DITER VON WETTSTEINt, AND C. NEIL HUNTER* *Krebs Institute for Biomolecular Research and Robert Hill Institute for Photosynthesis, Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN, United Kingdom; and tCarlsberg Laboratory, Department of Physiology, Gamle Carlsberg Vej 10, DK-2500 Copenhagen Valby, Denmark Contributed by Diter von Wettstein, November 14, 1994 ABSTRACT Magnesium-protoporphyrin chelatase lies at Escherichia coli and demonstrate that the extracts of the E. coli the branch point of the heme and (bacterio)chlorophyll bio- transformants can convert Mg-protoporphyrin IX to Mg- synthetic pathways. In this work, the photosynthetic bacte- protoporphyrin monomethyl ester (20, 21). Apart from posi- rium Rhodobacter sphaeroides has been used as a model system tively identifying bchM as the gene encoding the Mg- for the study of this reaction. The bchH and the bchI and -D protoporphyrin methyltransferase, this work opens up the genes from R. sphaeroides were expressed in Escherichia coli. possibility of extending this approach to other parts of the When cell-free extracts from strains expressing BchH, BchI, pathway. In this paper, we report the expression of the genes and BchD were combined, the mixture was able to catalyze the bchH, -I, and -D from R. sphaeroides in E. coli: extracts from insertion of Mg into protoporphyrin IX in an ATP-dependent these transformants, when combined in vitro, are highly active manner.
    [Show full text]
  • UTMB Testing Packet/Order Form
    Galveston Porphyria Laboratory The University of Texas Medical Branch Galveston, Texas Instructions for Collecting, Processing and Shipping Samples for Porphyria Testing This packet contains the following: • Instructions for collecting, processing and shipping samples • Order form for testing • A primer on laboratory testing for porphyrias Updated 9 June 2021 Page 1 Instructions for Collecting, Processing and Shipping Samples I. Sample Collection and Processing GENERAL INSTRUCTIONS 1. Types of samples used for porphyria testing (For choice of tests, see the attached Primer): a. Urine – spot (random or single void) urine sample is recommended with no preservative. A first-void sample on arising in the morning is preferred. i. Creatinine is measured on all urine samples for “normalization” of the results. The amount of creatinine excreted every day is quite constant because it reflects muscle mass. Most adults excrete 1-2 grams of creatinine daily in urine. Expressing results per gram of creatinine corrects for variation in the hydration state of the patient over time. The sample should be light protected (e.g. by wrapping the container in aluminum foil) and immediately refrigerated or frozen. ii. A 24-hour collection is also suitable, but 5 gm of sodium carbonate (not sodium bicarbonate) should be added to the container before starting the collection, the container should be refrigerated and protected from light during the collection (e.g. by using a dark-colored plastic collection bottle). The total volume must be measured in a single container and only a portion (an “aliquot”) sent to the laboratory for testing. Detailed instructions on how to properly collect a 24-hour urine must be given verbally to the patient along with the container containing the preservative.
    [Show full text]
  • PROTOPORPHYRIN IX Free Erythrocyte and Zincprotoporphyrin in WHOLE BLOOD by FLUORIMETRY – FAST – CODE Z39110
    PROTOPORPHYRIN IX free erythrocyte and ZincPROTOPORPHYRIN IN WHOLE BLOOD BY FLUORIMETRY – FAST – CODE Z39110 BIOCHEMISTRY The determination of ZincProtoporphyrin erythrocyte (ZPP-WB) has been used as an indicator of lead intoxication. The risk of exposure to lead in the population at large is different from that in occupational settings. In the latter, the main route of absorption is through respiratory inhalation. After absorption, lead is transported to the blood, where it is equally distributed in red blood cells and plasma; then it reaches diverse organs and tissues, and is deposited mainly in bone. Lead inhibits the biosynthesis of hemoglobin in red blood cells; by blocking ferrochelatase, it obstructs the binding of iron to Protoporphyrin IX, which in turn binds to zinc, forming ZincProtoporphyrin (ZPP). As a result, the concentration of ZPP in the red blood cell increases and that of hemoglobin decreases, leading to normocytic hypochromic anemia and high levels of serum iron. Protoporphyrin IX is an important precursor of biologically essential prosthetic groups such as heme, cytochrome C and chlorophylls. As a result, a number of organisms are able to synthesize this tetrapyrrole from basic precursors such as glycine and succinyl-CoA, or glutamate. Despite the wide range of organisms that synthesize Protoporphyrin IX, the process is largely preserved by bacteria to mammals, with some distinct exceptions in higher plants. Porphyrias are a group of hereditary disorders resulting from enzymatic defects in the biosynthetic pathway of heme. Depending on the specific enzyme involved, various porphyrins and their precursors accumulate in different types of samples. Patterns of porphyrin accumulation in erythrocytes and plasma and excretion of heme precursors in urine and faeces allow to detect and differentiate porphyrins.
    [Show full text]
  • Studies on the Mechanism of Sn-Protoporphyrin Suppression of Hyperbilirubinemia
    Studies on the mechanism of Sn-protoporphyrin suppression of hyperbilirubinemia. Inhibition of heme oxidation and bilirubin production. C S Simionatto, … , G S Drummond, A Kappas J Clin Invest. 1985;75(2):513-521. https://doi.org/10.1172/JCI111727. Research Article The synthetic heme analogue Sn-protoporphyrin is a potent competitive inhibitor of heme oxygenase, the rate-limiting enzyme in heme degradation to bile pigment, and can entirely suppress hyperbilirubinemia in neonatal animals and significantly reduce plasma bilirubin levels in a variety of circumstances in experimental animals and man. To further explore the mechanism by which this metalloporphyrin reduces bilirubin levels in vivo, we have examined its effects on bilirubin production in bile duct-cannulated rats, in which bilirubin derived from heme catabolism is known to be rapidly excreted in bile. The administration of Sn-protoporphyrin (10-50 mumol/kg body weight) was followed by prompt (within approximately 1 h) and sustained (up to at least 18 h) decreases in bilirubin output, to levels 25-30 percent below the levels of bilirubin output in control bile fistula animals. The metalloporphyrin had no effect on bile flow or the biliary output of bile acids. Infusions of heme, which is taken up primarily in hepatocytes, or of heat-damaged erythrocytes, which are taken up in reticuloendothelial cells, resulted in marked increases in bilirubin output in bile in control animals; these increases were completely prevented or substantially diminished by Sn-protoporphyrin administration. By contrast, the metalloporphyrin did not alter the high levels of bilirubin in plasma and bile that were achieved in separate experiments by the constant (16 h) infusion of unconjugated bilirubin […] Find the latest version: https://jci.me/111727/pdf Studies on the Mechanism of Sn-Protoporphyrin Suppression of Hyperbilirubinemia Inhibition of Heme Oxidation and Bilirubin Production Creuza S.
    [Show full text]
  • A Primitive Pathway of Porphyrin Biosynthesis and Enzymology in Desulfovibrio Vulgaris
    Proc. Natl. Acad. Sci. USA Vol. 95, pp. 4853–4858, April 1998 Biochemistry A primitive pathway of porphyrin biosynthesis and enzymology in Desulfovibrio vulgaris TETSUO ISHIDA*, LING YU*, HIDEO AKUTSU†,KIYOSHI OZAWA†,SHOSUKE KAWANISHI‡,AKIRA SETO§, i TOSHIRO INUBUSHI¶, AND SEIYO SANO* Departments of *Biochemistry and §Microbiology and ¶Division of Biophysics, Molecular Neurobiology Research Center, Shiga University of Medical Science, Seta, Ohtsu, Shiga 520-21, Japan; †Department of Bioengineering, Faculty of Engineering, Yokohama National University, 156 Tokiwadai, Hodogaya-ku, Yokohama 240, Japan; and ‡Department of Public Health, Graduate School of Medicine, Kyoto University, Sakyou-ku, Kyoto 606, Japan Communicated by Rudi Schmid, University of California, San Francisco, CA, February 23, 1998 (received for review March 15, 1998) ABSTRACT Culture of Desulfovibrio vulgaris in a medium billion years ago (3). Therefore, it is important to establish the supplemented with 5-aminolevulinic acid and L-methionine- biosynthetic pathway of porphyrins in D. vulgaris, not only methyl-d3 resulted in the formation of porphyrins (sirohydro- from the biochemical point of view, but also from the view- chlorin, coproporphyrin III, and protoporphyrin IX) in which point of molecular evolution. In this paper, we describe a the methyl groups at the C-2 and C-7 positions were deuter- sequence of intermediates in the conversion of uroporphy- ated. A previously unknown hexacarboxylic acid was also rinogen III to coproporphyrinogen III and their stepwise isolated, and its structure was determined to be 12,18- enzymic conversion. didecarboxysirohydrochlorin by mass spectrometry and 1H NMR. These results indicate a primitive pathway of heme biosynthesis in D. vulgaris consisting of the following enzy- MATERIALS AND METHODS matic steps: (i) methylation of the C-2 and C-7 positions of Materials.
    [Show full text]
  • Effects of Iron and Oxygen on Chlorophyll Biosynthesis' I
    Plant Physiol. (1982) 69, 107-1 1 1 0032-0889/82/69/0107/05/$00.50/0 Effects of Iron and Oxygen on Chlorophyll Biosynthesis' I. IN VIVO OBSERVATIONS ON IRON AND OXYGEN-DEFICIENT PLANTS Received for publication March 31, 1981 and in revised form July 31, 1981 SUSAN C. SPILLER, ANN M. CASTELFRANCO2, AND PAUL A. CASTELFRANCOQ Department ofBotany, University of Cal!fornia, Davis, California 95616 ABSTRACT ALA4 (3). It is probable that this in vivo 02 requirement, in part, reflects the need for molecular O2 in aerobic respiration, which is Corn (Zea mnays, L.), bean (Phaseolus vulgaris L.), barley (Hordeum necessary to generate ATP in the common test plants (e.g. cucum- vudgare L.), spinach (Spuiacia oeracea L.), and sugarbeet (Beta vulgaris ber, bean, barley). L.) grown under iron deficiency, and Potamogeton pectinatus L, and Pota- In the present paper we are reporting on: (a) the accumulation mogeton nodosus Poir. grown under oxygen deficiency, contained less of Mg-Proto(Me) in vivo by Fe and 02-deficient plants; (b) the chlorophyll than the controls, but accumulated Mg-protoporphyrin IX and/ effect of Fe and O2 deficiency on the conversion of exogenous or Mg-protoporphyrin IX monomethyl ester. No significant accumulation ALA to Pchlide by plant tissue segments. The following article by of these intermediates was detected in the controls or in the tissue of Chereskin and Castelfranco (5) deals with the inhibition of ALA plants stressed by S, Mg, N deficiency, or by prolonged dark treatment. synthesis by Fe- and Mg-containing tetrapyrroles, and the effects Treatment of normal plant tissue with 8-aminolevulinic acid in the dark of Fe-chelators and anaerobiosis on the conversion of Mg-Proto resulted in the accumulation of protochlorophyliide.
    [Show full text]
  • Significance of Heme and Heme Degradation in the Pathogenesis Of
    International Journal of Molecular Sciences Review Significance of Heme and Heme Degradation in the Pathogenesis of Acute Lung and Inflammatory Disorders Stefan W. Ryter Proterris, Inc., Boston, MA 02118, USA; [email protected] Abstract: The heme molecule serves as an essential prosthetic group for oxygen transport and storage proteins, as well for cellular metabolic enzyme activities, including those involved in mitochondrial respiration, xenobiotic metabolism, and antioxidant responses. Dysfunction in both heme synthesis and degradation pathways can promote human disease. Heme is a pro-oxidant via iron catalysis that can induce cytotoxicity and injury to the vascular endothelium. Additionally, heme can modulate inflammatory and immune system functions. Thus, the synthesis, utilization and turnover of heme are by necessity tightly regulated. The microsomal heme oxygenase (HO) system degrades heme to carbon monoxide (CO), iron, and biliverdin-IXα, that latter which is converted to bilirubin-IXα by biliverdin reductase. Heme degradation by heme oxygenase-1 (HO-1) is linked to cytoprotection via heme removal, as well as by activity-dependent end-product generation (i.e., bile pigments and CO), and other potential mechanisms. Therapeutic strategies targeting the heme/HO-1 pathway, including therapeutic modulation of heme levels, elevation (or inhibition) of HO-1 protein and activity, and application of CO donor compounds or gas show potential in inflammatory conditions including sepsis and pulmonary diseases. Keywords: acute lung injury; carbon monoxide; heme; heme oxygenase; inflammation; lung dis- ease; sepsis Citation: Ryter, S.W. Significance of Heme and Heme Degradation in the Pathogenesis of Acute Lung and Inflammatory Disorders. Int. J. Mol. 1. Introduction Sci.
    [Show full text]
  • The Function of PROTOPORPHYRINOGEN IX OXIDASE in Chlorophyll Biosynthesis Requires Oxidised Plastoquinone in Chlamydomonas Reinh
    The function of PROTOPORPHYRINOGEN IX OXIDASE in chlorophyll biosynthesis requires oxidised plastoquinone in Chlamydomonas reinhardtii Pawel Brzezowski, Brigitte Ksas, Michel Havaux, Bernhard Grimm, Marie Chazaux, Gilles Peltier, Xenie Johnson, Jean Alric To cite this version: Pawel Brzezowski, Brigitte Ksas, Michel Havaux, Bernhard Grimm, Marie Chazaux, et al.. The function of PROTOPORPHYRINOGEN IX OXIDASE in chlorophyll biosynthesis requires oxidised plastoquinone in Chlamydomonas reinhardtii. Communications Biology, Nature Publishing Group, 2019, 2, pp.159. 10.1038/s42003-019-0395-5. cea-02149191 HAL Id: cea-02149191 https://hal-cea.archives-ouvertes.fr/cea-02149191 Submitted on 6 Jun 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License ARTICLE https://doi.org/10.1038/s42003-019-0395-5 OPEN The function of PROTOPORPHYRINOGEN IX OXIDASE in chlorophyll biosynthesis requires oxidised plastoquinone in Chlamydomonas reinhardtii 1234567890():,; Pawel Brzezowski 1,2, Brigitte Ksas3, Michel Havaux3, Bernhard Grimm2, Marie Chazaux1, Gilles Peltier1, Xenie Johnson 1 & Jean Alric 1 In the last common enzymatic step of tetrapyrrole biosynthesis, prior to the branching point leading to the biosynthesis of heme and chlorophyll, protoporphyrinogen IX (Protogen) is oxidised to protoporphyrin IX (Proto) by protoporphyrinogen IX oxidase (PPX).
    [Show full text]
  • Porphyrins and Bile Pigments: Metabolism and Disorders Dr
    Porphyrins and bile pigments: metabolism and disorders Dr. Jaya Chaturvedi Porphyrins • Porphyrins are cyclic compounds formed by the linkage of four pyrrole rings through methyne (ÓHC—) bridges.In the naturally occurring porphyrins, various side chains replace the eight numbered hydrogen atoms of the pyrroles. • Porphyrins have had different structures depend on side chains that are attached to each of the four pyrrole rings. For example; Uroporphyrin, coporporphyyrin and protoporphyrin IX (heme). • The most prevalent metalloporphyrin in humans is heme, which consists of one ferrous (Fe2+) iron ion coordinated at the center of the tetrapyrrole ring of protoporphyrin IX. What is bilirubin? •Bilirubin is a yellowish pigment found in bile, a fluid made by the liver. •The breakdown product of Hgb from injured RBCs and other heme containing proteins. •Produced by reticuloendothelial system •Released to plasma bound to albumin •Hepatocytes conjugate it and excrete through bile channels into small intestine. Bilirubin di-glucoronid Structure of heme: • Heme structure: a porphyrin ring coordinated with an atom of iron side chains: methyl, vinyl, propionyl • Heme is complexed with proteins to form: • Hemoglobin, myoglobin and cytochromes Pathway of Heme Biosynthesis. Heme biosynthesis begins in the mitochondria from glycine and succinyl- CoA, continues in the cytosol, and ultimately is completed within the mitochondria. The heme that it produced by this biosynthetic pathway is identified as heme b. PBG: porphobilinogen; ALA: δ- aminolevulinic
    [Show full text]
  • In Vitro DNA-Damaging Effects of Intestinal and Related Tetrapyrroles in Human Cancer Cells
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector EXPERIMENTAL CELL RESEARCH 319 (2013) 536–545 Available online at www.sciencedirect.com journal homepage: www.elsevier.com/locate/yexcr Research Article In vitro DNA-damaging effects of intestinal and related tetrapyrroles in human cancer cells Christine Mo¨lzera,Ã, Barbara Pflegera, Elisabeth Putza, Antonia Roßmanna, Ursula Schwarza, Marlies Wallnera, Andrew C. Bulmerb, Karl-Heinz Wagnera,b aDepartment of Nutritional Sciences, Emerging Field Oxidative Stress and DNA Stability, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria bHeart Foundation Research Centre, Griffith Health Institute, Griffith University (Gold Coast Campus), Queensland 4222, Australia article information abstract Article Chronology: Epidemiological studies report a negative association between circulating bilirubin concentra- Received 4 September 2012 tions and the risk for cancer and cardiovascular disease. Structurally related tetrapyrroles also Received in revised form possess in vitro anti-genotoxic activity and may prevent mutation prior to malignancy. 3 December 2012 Furthermore, few data suggest that tetrapyrroles exert anti-carcinogenic effects via induction Accepted 4 December 2012 of cell cycle arrest and apoptosis. To further investigate whether tetrapyrroles provoke DNA- Available online 13 December 2012 damage in human cancer cells, they were tested in the single cell gel electrophoresis assay Keywords: (SCGE). Eight tetrapyrroles (unconjugated bilirubin, bilirubin ditaurate, biliverdin, biliverdin-/ Stercobilin bilirubin dimethyl ester, urobilin, stercobilin and protoporphyrin) were added to cultured Caco2 Urobilin and HepG2 cells and their effects on comet formation (% tail DNA) were assessed. Flow Protoporphyrin cytometric assessment (apoptosis/necrosis, cell cycle, intracellular radical species generation) SCGE assisted in revealing underlying mechanisms of intracellular action.
    [Show full text]
  • Intrinsic Fluorescence of Protoporphyrin IX from Blood Samples Can Yield Information on the Growth of Prostate Tumours
    J Fluoresc (2010) 20:1159–1165 DOI 10.1007/s10895-010-0662-9 ORIGINAL PAPER Intrinsic Fluorescence of Protoporphyrin IX from Blood Samples Can Yield Information on the Growth of Prostate Tumours Flávia Rodrigues de Oliveira Silva & Maria Helena Bellini & Vivian Regina Tristão & Nestor Schor & Nilson Dias Vieira Jr. & Lilia Coronato Courrol Received: 12 November 2009 /Accepted: 30 March 2010 /Published online: 24 April 2010 # Springer Science+Business Media, LLC 2010 Abstract Prostate cancer is one of the most common types in those with prostate cancer induced by inoculation of of cancer in men, and unfortunately many prostate tumours DU145 cells. A significant contrast between the blood of remain asymptomatic until they reach advanced stages. normal and cancer subjects could be established. Blood Diagnosis is typically performed through Prostate-Specific porphyrin fluorophore showed an enhancement on the Antigen (PSA) quantification, Digital Rectal Examination fluorescence band around 632 nm following tumour (DRE) and Transrectal Ultrasonography (TU). The antigen growth. Fluorescence detection has advantages over other (PSA) is secreted by all prostatic epithelial cells and not light-based investigation methods: high sensitivity, high exclusively by cancerous ones, so its concentration also speed and safety. However it does carry the drawback of increases in the presence of other prostatic diseases. DRE low specificity of detection. The extraction of blood and TU are not reliable for early detection, when porphyrin using acetone can solve this problem, since histological analysis of prostate tissue obtained from a optical excitation of further molecular species can be biopsy is necessary. In this context, fluorescence techniques excluded, and light scattering from blood samples is are very important for the diagnosis of cancer.
    [Show full text]