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Sung VMH. Mechanistic overview of ADP-ribosylation reactions. Biochimie 2015; 113:35-46. [PMID: 25828806 DOI: 10.1016/j.biochi.2015.03.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Accepted: 03/20/2015] [Indexed: 10/23/2022]
Abstract
ADP-ribosylation reactions consist of mono-ADP-ribosylation, poly-ADP-ribosylation and cyclic ADP-ribosylation. These reactions play essential roles in many important physiological and pathophysiological events. The types of chemical linkages, the evolutionarily conserved motif within the enzymes to determine the target specificity, stereochemistry of the ADP-ribosylated products, and the chemical reactions taking place among the enzymes and substrates are discussed.
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Affiliation(s)
- Vicky M-H Sung
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Harvard University, MA 02115, USA.
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2
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Schaffrath R, Abdel-Fattah W, Klassen R, Stark MJR. The diphthamide modification pathway from Saccharomyces cerevisiae--revisited. Mol Microbiol 2014; 94:1213-26. [PMID: 25352115 DOI: 10.1111/mmi.12845] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2014] [Indexed: 01/09/2023]
Abstract
Diphthamide is a conserved modification in archaeal and eukaryal translation elongation factor 2 (EF2). Its name refers to the target function for diphtheria toxin, the disease-causing agent that, through ADP ribosylation of diphthamide, causes irreversible inactivation of EF2 and cell death. Although this clearly emphasizes a pathobiological role for diphthamide, its physiological function is unclear, and precisely why cells need EF2 to contain diphthamide is hardly understood. Nonetheless, the conservation of diphthamide biosynthesis together with syndromes (i.e. ribosomal frame-shifting, embryonic lethality, neurodegeneration and cancer) typical of mutant cells that cannot make it strongly suggests that diphthamide-modified EF2 occupies an important and translation-related role in cell proliferation and development. Whether this is structural and/or regulatory remains to be seen. However, recent progress in dissecting the diphthamide gene network (DPH1-DPH7) from the budding yeast Saccharomyces cerevisiae has significantly advanced our understanding of the mechanisms required to initiate and complete diphthamide synthesis on EF2. Here, we review recent developments in the field that not only have provided novel, previously overlooked and unexpected insights into the pathway and the biochemical players required for diphthamide synthesis but also are likely to foster innovative studies into the potential regulation of diphthamide, and importantly, its ill-defined biological role.
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Affiliation(s)
- Raffael Schaffrath
- Department of Genetics, University of Leicester, Leicester, LE1 7RH, UK; Institut für Biologie, Abteilung Mikrobiologie, Universität Kassel, 34132, Kassel, Germany
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3
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Abstract
Eukaryotic and archaeal elongation factor 2 contains a unique post-translationally modified histidine residue, named diphthamide. Genetic and biochemical studies have revealed that diphthamide biosynthesis involves a multi-step pathway that is evolutionally conserved among lower and higher eukaryotes. During certain bacterial infections, diphthamide is specifically recognized by bacterial toxins, including diphtheria toxin, Pseudomonas exotoxin A and cholix toxin. Although the pathological relevance is well studied, the physiological function of diphthamide is still poorly understood. Recently, many new interesting developments in understanding the biosynthesis have been reported. Here, we review the current understanding of the biosynthesis and biological function of diphthamide.
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Affiliation(s)
- Xiaoyang Su
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA
| | - Zhewang Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA
| | - Hening Lin
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA
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4
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Weldon JE, Pastan I. A guide to taming a toxin--recombinant immunotoxins constructed from Pseudomonas exotoxin A for the treatment of cancer. FEBS J 2011; 278:4683-700. [PMID: 21585657 PMCID: PMC3179548 DOI: 10.1111/j.1742-4658.2011.08182.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pseudomonas exotoxin A (PE) is a highly toxic protein secreted by the opportunistic pathogen Pseudomonas aeruginosa. The modular structure and corresponding mechanism of action of PE make it amenable to extensive modifications that can redirect its potent cytotoxicity from disease to a therapeutic function. In combination with a variety of artificial targeting elements, such as receptor ligands and antibody fragments, PE becomes a selective agent for the elimination of specific cell populations. This review summarizes our current understanding of PE, its intoxication pathway, and the ongoing efforts to convert this toxin into a treatment for cancer.
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Affiliation(s)
- John E Weldon
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA
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5
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Combining affinity purification by ADP-ribose-binding macro domains with mass spectrometry to define the mammalian ADP-ribosyl proteome. Proc Natl Acad Sci U S A 2009; 106:4243-8. [PMID: 19246377 DOI: 10.1073/pnas.0900066106] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Mono-ADP-ribosylation is a reversible posttranslational modification that modulates the function of target proteins. The enzymes that catalyze this reaction in mammalian cells are either bacterial pathogenic toxins or endogenous cellular ADP-ribosyltransferases. For the latter, both the enzymes and their targets have largely remained elusive, mainly due to the lack of specific techniques to study this reaction. The recent discovery of the macro domain, a protein module that interacts selectively with ADP-ribose, prompted us to investigate whether this interaction can be extended to the identification of ADP-ribosylated proteins. Here, we report that macro domains can indeed be used as selective baits for high-affinity purification of mono-ADP-ribosylated proteins, which can then be identified by mass spectrometry. Using this approach, we have identified a series of cellular targets of ADP-ribosylation reactions catalyzed by cellular ADP-ribosyltransferases and toxins. These proteins include most of the known targets of ADP-ribosylation, indicating the validity of this method, and a large number of other proteins, which now need to be individually validated. This represents an important step toward the discovery of new ADP-ribosyltransferase targets and an understanding of the physiological role and the pharmacological potential of this protein modification.
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6
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Zhang Y, Liu S, Lajoie G, Merrill AR. The role of the diphthamide-containing loop within eukaryotic elongation factor 2 in ADP-ribosylation by Pseudomonas aeruginosa exotoxin A. Biochem J 2008; 413:163-74. [PMID: 18373493 DOI: 10.1042/bj20071083] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
eEF2 (eukaryotic elongation factor 2) contains a post-translationally modified histidine residue, known as diphthamide, which is the specific ADP-ribosylation target of diphtheria toxin, cholix toxin and Pseudomonas aeruginosa exotoxin A. Site-directed mutagenesis was conducted on residues within the diphthamide-containing loop (Leu693-Gly703) of eEF2 by replacement with alanine. The purified yeast eEF2 mutant proteins were then investigated to determine the role of this loop region in ADP-ribose acceptor activity of elongation factor 2 as catalysed by exotoxin A. A number of single alanine substitutions in the diphthamide-containing loop caused a significant reduction in the eEF2 ADP-ribose acceptor activities, including two strictly conserved residues, His694 and Asp696. Analysis by MS revealed that all of these mutant proteins lacked the 2'-modification on the His699 residue and that eEF2 is acetylated at Lys509. Furthermore, it was revealed that the imidazole ring of Diph699 (diphthamide at position 699) still functions as an ADP-ribose acceptor (albeit poorly), even without the diphthamide modification on the His699. Therefore, this diphthamide-containing loop plays an important role in the ADP-ribosylation of eEF2 catalysed by toxin and also for modification of His699 by the endogenous diphthamide modification machinery.
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Affiliation(s)
- Yong Zhang
- Department of Molecular and Cellular Biology, Biophysics Interdepartmental Group, University of Guelph, Guelph, ON, Canada
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7
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Zhang SH, Yao JH, Song HD, Wang L, Xue JL. Cloning and expression of translation elongation factor 2 (EF-2) in zebrafish. ACTA ACUST UNITED AC 2008; 19:1-7. [PMID: 18300156 DOI: 10.1080/10425170500332314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
We have identified a developmentally regulated gene translation elongation factor 2 (EF-2) in zebrafish (GenBank Accession No. AAQ91234). Analysis of DNA sequence of zebrafish EF-2 shows that the 2826 bp cDNA spans an open reading frame from nucleotide 55 to 2631 and encodes a protein of 858 amino acids. It shares an identity of 92, 93, 93, 92, 79 and 80% in amino acid sequence to human, mouse, Chinese hamster, Gallus gullus, C. elegans and Drosophila EF-2, respectively. Zebrafish EF-2 protein has 16 conserved domains, GTP-binding domain is found in the NH2 terminus, and the ADP-ribosylation domain locates at the COOH terminus. Whole mount in situ hybridization on zebrafish embryos shows that the transcripts of EF-2 gene are detected during the early development of zebrafish embryo and constantly change from 5-somite stage to protruding-mouth stage. It expresses strongly throughout envelope at 5-somite stage. Then the stained cells concentrate strongly in the eyes, brain and muscle tissue. From prim-25 stage the stained cells only appear strongly in the lens and the anterior portion of the cerebellum.
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Affiliation(s)
- Shu-Hong Zhang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, People's Republic of China
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8
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Qiu L, Jiang S, Zhou F, Zhang D, Huang J, Guo Y. Molecular cloning of the black tiger shrimp (Penaeus monodon) elongation factor 2 (EF-2): sequence analysis and its expression on the ovarian maturation stage. Mol Biol Rep 2007; 35:431-8. [PMID: 17629788 DOI: 10.1007/s11033-007-9103-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Accepted: 05/08/2007] [Indexed: 10/23/2022]
Abstract
The techniques of homology cloning and anchored PCR were used to clone the elongation factor 2 (EF-2) gene from black tiger shrimp (Penaeus monodon). The full length cDNA of black tiger shrimp EF-2 (btsEF-2) contained a 5' untranslated region (UTR) of 73 bp, an ORF of 2541 bp encoding a polypeptide of 846 amino acids with an estimated molecular mass of 95 kDa, and a 3( UTR of 112 bp. The searches for protein sequence similarities with BLAST analysis indicated that the deduced amino acid sequence of btsEF-2 was homological to the EF-2 of other species and even the mammalians. The conserved signature sequence of EF-2 gene family, GTPase effector domain and ADP-ribosylation domain were found in the btsEF-2 deduced amino acid sequence. The temporal expressions of gene in the different ovarian stages were measured by real time PCR. The mRNA expressions of the gene were constitutively expressed in ovary and different during the maturation stages. The result indicated that EF-2 gene was constitutively expressed and could play a critical role in the ovarian maturation stage.
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Affiliation(s)
- Lihua Qiu
- Biotechnology and Aquiculture Laboratory, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingangxi Road, Guangzhou, P.R. China
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9
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Bektaş M, Nurten R, Ergen K, Bermek E. Endogenous ADP-ribosylation for eukaryotic elongation factor 2: evidence of two different sites and reactions. Cell Biochem Funct 2006; 24:369-80. [PMID: 16142694 DOI: 10.1002/cbf.1265] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Eukaryotic elongation factor 2 can undergo ADP-ribosylation in the absence of diphtheria toxin under the action of an endogenous transferase. The investigation which aimed to gain insight into the nature of endogenous ADP-ribosylation revealed that this reaction may be, in some cases, due to covalent binding of free ADP-ribose to elongation factor 2. Binding of free ADP-ribose, and NAD- and endogenous transferase-dependent ADP-ribosylation were suggested to be distinct reactions by different findings. Free ADP-ribose could bind to elongation factor 2 previously subjected to ADP-ribosylation by diphtheria toxin or endogenous transferase. The binding of free ADP-ribose was inhibited by neutral NH2OH, L-lysine and picrylsulfonate, whereas endogenous ADP-ribosyltransferase was inhibited by NAD glycohydrolase inhibitors and L-arginine. The ADP-ribosyl-elongation factor 2 adduct which formed upon binding of free ADP-ribose was resistant to neutral NH2OH, but decomposed almost completely upon treatment with NaOH. The product of endogenous transferase-dependent ADP- ribosylation was partially resistant to NH2OH and NaOH treatment. Moreover, this reaction was reversed in the presence of diphtheria toxin and nicotinamide. Both types of endogenous ADP-ribosylation gave rise to inhibition of polyphenylalanine synthesis. This study thus provides evidence for the presence of two different types of endogenous ADP-ribosylation of eukaryotic elongation factor 2. The respective sites involved in these reactions are distinct from one another as well as from diphthamide, the site of attack by diphtheria toxin.
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Affiliation(s)
- Muhammet Bektaş
- Istanbul University, Istanbul Faculty of Medicine, Department of Biophysics, 34390 Capa, Istanbul, Turkey.
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10
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Pastrana DV, FitzGerald DJ. A nonradioactive, cell-free method for measuring protein synthesis inhibition by Pseudomonas exotoxin. Anal Biochem 2006; 353:266-71. [PMID: 16647035 DOI: 10.1016/j.ab.2006.03.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2006] [Revised: 03/15/2006] [Accepted: 03/22/2006] [Indexed: 11/25/2022]
Abstract
Pseudomonas exotoxin A (PE) inhibits protein synthesis by NAD-dependent ADP-ribosylation of eukaryotic elongation factor 2. Traditionally, toxin activity has been characterized, either in living cells or cell-free systems, using radioactive compounds for quantification. The increased costs of radioactive waste disposal together with heightened security concerns have made the use of radioactive isotopes less attractive for routine laboratory assays. We therefore adapted a cell-free rabbit reticulocyte in vitro transcription-translation system that utilizes a reporter (beta-galactosidase) to measure toxin activity. The assay for PE is rapid, scalable, log-linear, NAD dependent and can be used to assess the neutralizing activity of anti-PE antibody preparations.
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Affiliation(s)
- Diana V Pastrana
- Laboratory of Molecular Biology, CCR, National Cancer Institute, Bethesda, MD 20892-4263, USA
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11
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Yates SP, Jørgensen R, Andersen GR, Merrill AR. Stealth and mimicry by deadly bacterial toxins. Trends Biochem Sci 2006; 31:123-33. [PMID: 16406634 DOI: 10.1016/j.tibs.2005.12.007] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Revised: 11/21/2005] [Accepted: 12/21/2005] [Indexed: 11/19/2022]
Abstract
Diphtheria toxin and exotoxin A are well-characterized members of the ADP-ribosyltransferase toxin family that function as virulence factors in the pathogenic bacteria Corynebacterium diphtheriae and Pseudomonas aeruginosa. Recent high-resolution structural data of the Michaelis (enzyme-substrate) complex of the P. aeruginosa toxin with an NAD(+) analog and eukaryotic elongation factor 2 (eEF2) have provided insights into the mechanism of inactivation of protein synthesis caused by these protein factors. In addition, rigorous steady-state and stopped-flow kinetic analyses of the toxin-catalyzed reaction, in combination with inhibitor studies, have resulted in a quantum leap in our understanding of the mechanistic details of this deadly enzyme mechanism. It is now apparent that these toxins use stealth and molecular mimicry in unleashing their toxic strategy in the infected host eukaryotic cell.
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Affiliation(s)
- Susan P Yates
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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12
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Argüelles S, Machado A, Ayala A. "In vitro" effect of lipid peroxidation metabolites on elongation factor-2. Biochim Biophys Acta Gen Subj 2006; 1760:445-52. [PMID: 16469450 DOI: 10.1016/j.bbagen.2005.12.019] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2005] [Revised: 12/05/2005] [Accepted: 12/13/2005] [Indexed: 10/25/2022]
Abstract
Elongation Factor-2 (eEF-2) is the protein that catalyzes the translocation of the ribosome through mRNA. Not all oxidants affect eEF-2, which is extremely sensitive to oxidative stress caused mainly by lipid peroxidant compounds such as cumene hydroperoxide and t-butyl hydroperoxide. Lipid peroxides constitute a potential hazard to living organisms because of their direct reactivity with a variety of biomolecules and the ability to decompose into free radicals and reactive aldehydes. In this "in vitro" study, we show the effect of three of these aldehydes on the levels of hepatic eEF-2. The results suggest that the toxicity associated with prooxidant-mediated hepatic lipid peroxidation on protein synthesis can originate from the interaction of the aldehydic end products of lipid peroxidation with eEF-2.
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Affiliation(s)
- Sandro Argüelles
- Departamento de Bioquímica, Bromatología, Toxicología, Facultad de Farmacia, Universidad de Sevilla, C/.Tramontana s/n, 41012-Sevilla, Spain
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13
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Bektaş M, Akçakaya H, Aroymak A, Nurten R, Bermek E. Effect of oxidative stress on in vivo ADP-ribosylation of eukaryotic elongation factor 2. Int J Biochem Cell Biol 2005; 37:91-9. [PMID: 15381153 DOI: 10.1016/j.biocel.2004.05.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2004] [Revised: 05/24/2004] [Accepted: 05/24/2004] [Indexed: 11/16/2022]
Abstract
Different lines of evidence indicate that eukaryotic elongation factor 2 (eEF2) can be ADP-ribosylated endogenously. The physiological significance of this reaction has, however, remained unclarified. In order to address this issue we investigated the in vivo ADP-ribosylation of eEF2 and the effect of oxidative stress thereon. The investigation revealed that the endogenous ADP-ribosylation of eEF2 is complex and can take place in K562 cell lysates either under the action of endogenous transferase from [adenosine-14C]NAD or by direct binding of free [14C]ADP-ribose. These two types of ADP-ribosylation were distinguished by use of different treatments based on the chemical stability of the respective bonds formed. Under standard culture conditions, in vivo labeling of eEF2 in the presence of [14C]adenosine was reversed to about 65% in the presence of diphtheria toxin and nicotinamide. This finding implied that the modification that took place under physiological circumstances was, mainly, of an enzymic nature. On the other hand, H2O2-promoted oxidative stress gave rise to a nearly two-fold increase in the extent of in vivo labeling of eEF2. This was accompanied by a loss of eEF2 activity in polypeptide chain elongation. Oxidative stress specifically inhibited the subsequent binding of free ADP-ribose to eEF2. The results thus provide evidence that endogenous ADP-ribosylation of eEF2 can also take place by the binding of free ADP-ribose. This nonenzymic reaction appears to account primarily for in vivo ADP-ribosylation of eEF2 under oxidative stress.
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Affiliation(s)
- Muhammet Bektaş
- Department of Biophysics, Istanbul Faculty of Medicine, Istanbul University, 34390 Capa, Istanbul, Turkey.
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14
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Jørgensen R, Yates SP, Teal DJ, Nilsson J, Prentice GA, Merrill AR, Andersen GR. Crystal structure of ADP-ribosylated ribosomal translocase from Saccharomyces cerevisiae. J Biol Chem 2004; 279:45919-25. [PMID: 15316019 DOI: 10.1074/jbc.m406218200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The crystal structure of ADP-ribosylated yeast elongation factor 2 in the presence of sordarin and GDP has been determined at 2.6 A resolution. The diphthamide at the tip of domain IV, which is the target for diphtheria toxin and Pseudomonas aeruginosa exotoxin A, contains a covalently attached ADP-ribose that functions as a very potent inhibitor of the factor. We have obtained an electron density map of ADP-ribosylated translation factor 2 revealing both the ADP-ribosylation and the diphthamide. This is the first structure showing the conformation of an ADP-ribosylated residue and confirms the inversion of configuration at the glycosidic linkage. Binding experiments show that the ADP-ribosylation has limited effect on nucleotide binding affinity, on ribosome binding, and on association with exotoxin A. These results provide insight to the inhibitory mechanism and suggest that inhibition may be caused by erroneous interaction of the translation factor with the codon-anticodon area in the P-site of the ribosome.
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Affiliation(s)
- René Jørgensen
- Macromolecular Crystallography, Department of Molecular Biology, University of Aarhus, Gustav Wieds vej 10C, DK8000 Aarhus, Denmark
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15
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Malavé TM, Forney JD. Identification of a developmentally regulated translation elongation factor 2 in Tetrahymena thermophila. Gene 2004; 326:97-105. [PMID: 14729267 DOI: 10.1016/j.gene.2003.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Protein synthesis elongation factor 2 (eEF2) catalyzes the translocation of the peptidyl-tRNA from the A site to the P site of the ribosome. Most organisms encode a single EF2 protein and its activity is regulated by phosphorylation. We have identified a family of genes in Tetrahymena thermophila that encode proteins homologous to eEF2, yet are expressed only during sexual reproduction. These genes have been designated EFR for Elongation Factor 2 Related. EFR transcripts were not detected in vegetative cell cultures but rapidly increased about 6 h after the start of conjugation (mating). For comparison, we cloned, sequenced and analyzed the expression of the standard eEF2 gene from T. thermophila. Unlike EFR, transcripts from eEF2 were detected in vegetative cells but were present at lower concentrations during conjugation. Despite the high sequence identity between EFR and eEF2 from other organisms (about 42% at the amino acid level), key regulatory sequences that are involved in the regulation of eEF2 are altered in EFR. The sequence and expression data suggest that EFR is an eEF2 variant involved in a major translation regulatory mechanism that occurs during the formation of the macronuclear genome in conjugating cells.
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MESH Headings
- Amino Acid Sequence
- Animals
- Cloning, Molecular
- DNA, Protozoan/chemistry
- DNA, Protozoan/genetics
- Gene Expression Regulation, Developmental
- Molecular Sequence Data
- Peptide Elongation Factor 2/genetics
- Peptide Elongation Factors/genetics
- Protozoan Proteins/genetics
- RNA, Protozoan/genetics
- RNA, Protozoan/metabolism
- Regulatory Sequences, Nucleic Acid/genetics
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tetrahymena thermophila/genetics
- Tetrahymena thermophila/growth & development
- Transcription, Genetic
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Affiliation(s)
- Tania M Malavé
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
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16
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Jäger D, Holtz J, Redpath NT, Müller SP, Pönicke K, Heinroth-Hoffmann I, Werdan K, Müller-Werdan U. The ageing heart: influence of cellular and tissue ageing on total content and distribution of the variants of elongation factor-2. Mech Ageing Dev 2002; 123:1305-19. [PMID: 12297334 DOI: 10.1016/s0047-6374(02)00040-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The involvement of elongation factor-2 (EEF-2), a key-protein of peptide-chain elongation, in the slowing down of protein synthesis during cardiac ageing was addressed. EEF-2 was measured in rat heart extracts and isolated rat cardiomyocytes (CM) from newborn and adult rats using sodium-dodecylsulphate polyacrylamide gel electrophoresis after specific labeling with [32P]ADP-ribosylation or immunoblot. The age-dependent proportional content of several eucaryotic elongation factor-2 (eEF-2) subtypes in rat CM and rat heart extracts was compared using one-dimensional isoelectric focusing. EEF-2 was considerably reduced in the hearts of adult compared to neonatal rats (P<0.01). EEF-2 was also significantly decreased in isolated CM from adult versus newborn rats and during prolonged cultivation of neonatal CM. Cellular ageing was combined with reduced protein synthesis. During adolescence the eEF-2 variants shifted to acidic subtypes. Young adult and old rats revealed similar amounts and subtype distribution of cardiac eEF-2. Only the more acidic eEF-2 variants appeared to contain phosphorylated eEF-2. We concluded that total cardiac eEF-2 and its subtype pattern might play an important role in developmental and age-related proteomic changes.
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Affiliation(s)
- Doris Jäger
- Department of Medicine III, Martin-Luther University Halle-Wittenberg, Ernst-Grube Street 40, D-06097, Halle, Germany.
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Collier RJ. Understanding the mode of action of diphtheria toxin: a perspective on progress during the 20th century. Toxicon 2001; 39:1793-803. [PMID: 11595641 DOI: 10.1016/s0041-0101(01)00165-9] [Citation(s) in RCA: 228] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Diphtheria toxin is one of the most extensively studied and well understood bacterial toxins. Ever since its discovery in the late 1800's this toxin has occupied a central focus in the field of toxinology. In this review, I present a chronology of major discoveries that led to our current understanding of the structure and activity of diphtheria toxin.
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Affiliation(s)
- R J Collier
- Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
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18
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Schwab CJ, Colville MJ, Fullerton AT, McMahon KK. Evidence of endogenous mono-ADP-ribosylation of cardiac proteins via anti-ADP-ribosylarginine immunoreactivity. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 2000; 223:389-96. [PMID: 10721009 DOI: 10.1046/j.1525-1373.2000.22355.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Arginine-specific mono-ADP-ribosylation of proteins and arginine-specific mono-ADP-ribosyltransferase occur in heart. We developed a polyclonal antiserum, R-28, against ADP-ribosylpolyarginine that recognized mono-ADP-ribosylated proteins and identified the major mono-ADP-ribosylation products of quail heart. Treatment of Immobilon-bound ADP-ribosylated Gs protein with hydroxylamine under conditions that remove ADP-ribose from its arginines eliminated R-28 immunoreactivity to Gs. Also, R-28 immunoreactivity to quail heart proteins was removed by NaOH and phosphodiesterase I treatments. Similar treatment with mercuric chloride did not remove the immunoreactivity but did remove exogenously (via in vitro pertussis toxin treatment) added ADP-ribose from cysteine of cardiac Gi/Go proteins. The antiserum did not appear to react with ADP-ribosylasparagine of Rho (formed by C3 toxin), ADP-ribosyldiphthamide of elongation factor 2 (formed by diphtheria toxin) in quail heart preparations, or polyADP-ribosylated proteins of a neonate rat cardiac nuclear preparation. Thus, the R-28 antiserum appears to contain predominantly antibodies directed against ADP-ribosylarginine. To test the usefulness of R-28, immunoblotting of subcellular fractions of quail heart was performed. R-28 showed the greatest immunoreactivity in the sarcolemma with significant immunoreactivity in denser membrane fractions. The cytosol also contained an immunoreactive band distinct from those found in the membranes. Hydroxylamine treatment eliminated immunoreactivity in the sarcolemma and denser membrane fractions but not the cytosol, suggesting the membranous immunoreactive bands contain ADP-ribosylarginine. In conclusion, a polyclonal antiserum that recognizes ADP-ribosylarginine proteins has been raised. The usefulness of the antiserum is demonstrated by the characterization of endogenous arginine mono-ADP-ribosylation products in quail heart. The quail heart has several sarcolemmal and denser membrane fraction proteins that appear to be mono-ADP-ribosylated on arginines.
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Affiliation(s)
- C J Schwab
- Department of Pharmacology, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
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Falnes PO, Ariansen S, Sandvig K, Olsnes S. Requirement for prolonged action in the cytosol for optimal protein synthesis inhibition by diphtheria toxin. J Biol Chem 2000; 275:4363-8. [PMID: 10660606 DOI: 10.1074/jbc.275.6.4363] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Diphtheria toxin A-fragment enters the cytosol of target cells, where it inhibits protein synthesis by catalyzing ADP-ribosylation of elongation factor 2 (EF-2). We have here analyzed toxin-induced protein synthesis inhibition in single cells by autoradiography and compared it with inhibition of protein synthesis in the whole cell culture. The data show that half-maximal protein synthesis inhibition in the whole cell population after a short incubation time is achieved by partially inhibiting protein synthesis in basically all the cells, while half-maximal protein synthesis inhibition after a long incubation time is due to a complete protein synthesis block in about half the cells in the population. We have also compared stable and unstable A-fragment mutants with respect to the kinetics of cell intoxication. While the toxicity of the stable mutants increased with time, the unstable mutants showed a similar toxicity at early and late time points. When studying the kinetics of cell intoxication by toxins with short cytosolic half-life, we could not detect any recovery of protein synthesis at late time points when all the mutant A-fragments should be degraded. This indicates that the ADP-ribosylation of EF-2 cannot be reversed by an endogenous activity in the cells. The data indicate that entry of toxin into a cell is not associated with an immediate block in protein synthesis, and that prolonged action of single A-fragment molecules in the cytosol is sufficient to obtain complete protein synthesis inhibition at low toxin concentrations.
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Affiliation(s)
- P O Falnes
- Institute for Cancer Research, Norwegian Radium Hospital, Montebello, 0310 Oslo, Norway
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Brinkmann U, Brinkmann E, Gallo M, Scherf U, Pastan I. Role of CAS, a human homologue to the yeast chromosome segregation gene CSE1, in toxin and tumor necrosis factor mediated apoptosis. Biochemistry 1996; 35:6891-9. [PMID: 8639641 DOI: 10.1021/bi952829+] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have previously isolated by expression/selection cloning plasmids containing human cDNAs that rendered MCF-7 breast cancer cells resistant to immunotoxins, Pseudomonas exotoxin (PE), and diphtheria toxin (DT) [Brinkmann et al. (1995) Mol. Med. 1, 206-216]. Here we describe that one of these resistant plasmids, which contains an antisense cDNA fragment homologous to the yeast chromosome segregation gene CSE1 [CAS; Brinkmann et al. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 10427-10431], reduces the intracellular content of the human CSE1 homologue CAS protein. CAS reduction confers resistance not only to the ADP-ribosylating toxins PE and DT, but also to tumor necrosis factor alpha and beta. The resistance was observed as reduced apoptosis. CAS antisense did not affect the cell death induced by staurosporine, cycloheximide, or etoposide. The observation that CAS antisense can interfere with apoptosis mediated by TNF and ADP-ribosylating toxins suggests that CAS may play a role in selected pathways of apoptosis.
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Affiliation(s)
- U Brinkmann
- Laboratory of Molecular Biology, DBS, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, 20892-4255, USA
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Brinkmann U, Brinkmann E, Gallo M, Pastan I. Cloning and characterization of a cellular apoptosis susceptibility gene, the human homologue to the yeast chromosome segregation gene CSE1. Proc Natl Acad Sci U S A 1995; 92:10427-31. [PMID: 7479798 PMCID: PMC40810 DOI: 10.1073/pnas.92.22.10427] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We recently isolated human cDNA fragments that render MCF-7 breast cancer cells resistant to cell death caused by Pseudomonas exotoxin, Pseudomonas exotoxin-derived immunotoxins, diphtheria toxin, and tumor necrosis factor. We report here that one of these fragments is an antisense fragment of a gene homologous to the essential yeast chromosome segregation gene CSE1. Cloning and analysis of the full-length cDNA of the human CSE1 homologue, which we name CAS for cellular apoptosis susceptibility gene, reveals a protein coding region with similar length (971 amino acids for CAS, 960 amino acids for CSE1) and 59% overall protein homology to the yeast CSE1 protein. The conservation of this gene indicates it has an important function in human cells consistent with the essential role of CSE1 in yeast. CAS is highly expressed in human tumor cell lines and in human testis and fetal liver, tissues that contain actively dividing cells. Furthermore, CAS expression increases when resting human fibroblasts are induced to proliferate and decreases when they are growth-arrested. Thus, CAS appears to play an important role in both toxin and tumor necrosis factor-mediated cell death, as well as in cell proliferation.
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Affiliation(s)
- U Brinkmann
- Laboratory of Molecular Biology, National Cancer Institutes, National Institutes of Health, Bethesda, MD 20892-4255, USA
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Brinkmann U, Brinkmann E, Pastan I. Expression Cloning of cDNAs That Render Cancer Cells Resistant to Pseudomonas and Diphtheria Toxin and Immunotoxins. Mol Med 1995. [DOI: 10.1007/bf03401568] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Abstract
Mono-ADP-ribosylation appears to be a reversible modification of proteins, which occurs in many eukaryotic and prokaryotic organisms. Multiple forms of arginine-specific ADP-ribosyltransferases have been purified and characterized from avian erythrocytes, chicken polymorphonuclear leukocytes and mammalian skeletal muscle. The avian transferases have similar molecular weights of approximately 28 kDa, but differ in physical, regulatory and kinetic properties and subcellular localization. Recently, a 38-kDa rabbit skeletal muscle ADP-ribosyltransferase was purified and cloned. The deduced amino acid sequence contained hydrophobic amino and carboxy termini, consistent with known signal sequences of glycosylphosphatidylinositol (GPI)-anchored proteins. This arginine-specific transferase was present on the surface of mouse myotubes and of NMU cells transfected with the cDNA and was released with phosphatidylinositol-specific phospholipase C. Arginine-specific ADP-ribosyltransferases thus appear to exhibit considerable diversity in their structure, cellular localization, regulation and physiological role.
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Affiliation(s)
- A Zolkiewska
- Laboratory of Cellular Metabolism, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892
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Abstract
A cellular ADP-ribosyltransferase activity has been found in a variety of animals and tissues. The enzyme transfers ADP-ribose from NAD to elongation factor 2, inactivating the factor and thus inhibiting in vitro protein synthesis. Although, the mechanism of action of the cellular enzyme appears similar to diphtheria toxin and Pseudomonas exotoxin A, it differs from the toxins in that only a fraction of the EF-2 pool is modified. The endogenously ADP-ribosylated EF-2 has been detected by a variety of methods including two-dimensional electrophoresis and immunoprecipitation with elongation factor 2 antibody. The nature of the cellular ADP-ribosyltransferase and its physiological significance are unknown.
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Affiliation(s)
- W J Iglewski
- Department of Microbiology and Immunology, University of Rochester Medical Center, New York 14642
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Zolkiewska A, Nightingale MS, Moss J. Molecular characterization of NAD:arginine ADP-ribosyltransferase from rabbit skeletal muscle. Proc Natl Acad Sci U S A 1992; 89:11352-6. [PMID: 1454819 PMCID: PMC50548 DOI: 10.1073/pnas.89.23.11352] [Citation(s) in RCA: 143] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Mono-ADP-ribosylation is a reversible modification of proteins, with NAD:arginine ADP-ribosyltransferases (EC 2.4.2.31) and ADP-ribosylarginine hydrolases (EC 3.2.2.19) catalyzing the opposing reactions in an ADP-ribosylation cycle. A membrane-associated arginine-specific (mono)-ADP-ribosyltransferase was purified 215,000-fold from rabbit skeletal muscle. On the basis of the amino acid sequences of HPLC-purified tryptic peptides, degenerate oligonucleotide primers were synthesized and used in a polymerase chain reaction (PCR)-based procedure to generate cDNA. A specific probe, based on PCR-generated sequence, was used to screen a rabbit skeletal muscle cDNA library. A composite cDNA sequence, obtained from library screening and rapid amplification of the 5' end of the cDNA, contained a 981-base-pair open reading frame, encoding a 36,134-Da protein. The deduced amino acid sequence contained the sequences of the tryptic peptides, hydrophobic amino and carboxyl termini, and two potential sites for N-linked glycosylation. Escherichia coli cells transformed with an expression vector containing transferase-specific sequence expressed ADP-ribosyltransferase activity. A transferase-specific oligonucleotide probe recognized a 4-kilobase mRNA expressed primarily in rabbit skeletal and cardiac muscle. There was no extended similarity in deduced amino acid sequences of the muscle transferase and several bacterial ADP-ribosylating toxins. The hydrophobic amino and carboxyl termini may represent a signal peptide and a site for a glycosyl-phosphatidylinositol anchor, respectively.
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Affiliation(s)
- A Zolkiewska
- Laboratory of Cellular Metabolism, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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Siegmund KD, Klink F. Production of an antiserum specific to the ADP-ribosylated form of elongation factor 2 from archaebacteria and eukaryotes. FEBS Lett 1992; 312:139-42. [PMID: 1426243 DOI: 10.1016/0014-5793(92)80921-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
An antiserum to ADP-ribosylated elongation factor 2 (ADPR-EF-2) from S. acidocaldarius was raised in rabbits using stained, homogenized, ADPR-EF-2-containing slices from SDS-gels as a source of antigen. Elongation factor 2 (EF-2) from S. acidocaldarius was cloned in E. coli and the expressed gene product was used in order to adsorb all anti-EF-2 antibodies which do not contain the ADP-ribosyl group within their epitopes, as E. coli is unable to synthesize the ADP-ribosyl acceptor diphthamide. The remaining antibodies were specific to ADP-ribosylated EF-2 from Thermoplasma acidophilum, S. acidocaldarius and Desulfurococcus mucosus. ADP-ribosylated EF-2 from eukaryotic sources also reacted with the adsorbed antiserum as shown for EF-2 isolated from the killi-fish Cynolebias whitei, the mouse species BALB/c and Han/Wistar rats. The adsorbed antiserum did not cross-react with ADP-ribosylated actin or rho protein or with FAD-containing D-amino acid oxidase.
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Affiliation(s)
- K D Siegmund
- Biochemisches Institut, Christian-Albrechts Universität, Kiel, Germany
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