000051693 001__ 51693 000051693 005__ 20180211175142.0 000051693 0247_ $$2pmid$$apmid:15764393 000051693 0247_ $$2DOI$$a10.1080/09553000400017614 000051693 0247_ $$2WOS$$aWOS:000226521200009 000051693 0247_ $$2ISSN$$a0955-3002 000051693 037__ $$aPreJuSER-51693 000051693 041__ $$aeng 000051693 082__ $$a570 000051693 084__ $$2WoS$$aBiology 000051693 084__ $$2WoS$$aNuclear Science & Technology 000051693 084__ $$2WoS$$aRadiology, Nuclear Medicine & Medical Imaging 000051693 1001_ $$0P:(DE-Juel1)VDB1274$$aPomplun, E.$$b0$$uFZJ 000051693 245__ $$aIs Coulomb explosion a damaging mechanism for 125-IUdR? 000051693 260__ $$aLondon$$bTaylor & Francis$$c2004 000051693 300__ $$a 000051693 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article 000051693 3367_ $$2DataCite$$aOutput Types/Journal article 000051693 3367_ $$00$$2EndNote$$aJournal Article 000051693 3367_ $$2BibTeX$$aARTICLE 000051693 3367_ $$2ORCID$$aJOURNAL_ARTICLE 000051693 3367_ $$2DRIVER$$aarticle 000051693 440_0 $$015361$$aInternational Journal of Radiation Biology$$v80$$x0955-3002$$y11 000051693 500__ $$aRecord converted from VDB: 12.11.2012 000051693 520__ $$aTo test the integrity of the thymine molecule that experiences an increasing number of charges due to the loss of Auger electrons emitted by the decay of incorporated 125I. Besides the radiation action of these electrons, Coulomb explosion is suspected to be an additional mechanism responsible for the strong radiotoxic effect of decaying DNA-incorporated 125I. The two-step decay process initiates a first Auger cascade within 10(-16) to 10(-14) s resulting in the release of about 7 electrons on average and a corresponding large positive charge on the 125Te daughter atom. Being part of iododeoxyuridine (125IUdR), the analogue of the DNA base thymine, the base is suddenly confronted with this charge. Experimentally, the situation was investigated with small molecules (CH3(125)I and C2H5(125)I) resulting in ion fragmentation in agreement with a Coulomb explosion model (Carlson and White, 1963, 1966).Semi-empirical quantum mechanical calculations on the Parametric Method 3 (PM3) level (Stewart, 1989a, 1989b) were performed and geometry optimisation was applied for the identification of stable molecule conformations. Subsequently, semiempirical molecular dynamics simulations allowed changes in the conformations to be studied as a function of time.First results show that there is no stable molecular configuration with a total charge of > or = +5e. PM3 calculations will not converge for such a charge located at the 125I/125Te position. This finding is supported by total energy considerations, which begin to favour a system of isolated atoms versus molecular bound atoms when the molecular charge is greater than +4e. The distribution of the partial charges indicates that most of the charge will remain on the tellurium atom with slight increases of charge at the other molecular partners within 125IUdR. Moreover, the molecular dynamics simulations reveal a breaking of chemical bonds between those atoms with the strongest charge increase.Coulomb explosion must be taken into account as a possible damaging mechanism following the decay of DNA-incorporated Auger electron emitters. Lobachevsky and Martin (2000) have identified the same mechanism to be responsible for part of strand breakage in oligo-deoxynucleotides. To elucidate a possible link between both damage patterns the molecular mechanics simulations have to be extended to larger parts of the DNA molecule. 000051693 536__ $$0G:(DE-Juel1)FUEK254$$2G:(DE-HGF)$$aBetrieb und Weiterentwicklung des Höchstleistungsrechners$$cI03$$x0 000051693 588__ $$aDataset connected to Web of Science, Pubmed 000051693 650_2 $$2MeSH$$aComputer Simulation 000051693 650_2 $$2MeSH$$aDNA: chemistry 000051693 650_2 $$2MeSH$$aDNA: radiation effects 000051693 650_2 $$2MeSH$$aDNA Damage 000051693 650_2 $$2MeSH$$aDose-Response Relationship, Radiation 000051693 650_2 $$2MeSH$$aElectrons: adverse effects 000051693 650_2 $$2MeSH$$aIdoxuridine: chemistry 000051693 650_2 $$2MeSH$$aIdoxuridine: radiation effects 000051693 650_2 $$2MeSH$$aModels, Chemical 000051693 650_2 $$2MeSH$$aModels, Molecular 000051693 650_2 $$2MeSH$$aNucleic Acid Conformation: radiation effects 000051693 650_2 $$2MeSH$$aRadiation Dosage 000051693 650_2 $$2MeSH$$aStatic Electricity 000051693 650_7 $$054-42-2$$2NLM Chemicals$$aIdoxuridine 000051693 650_7 $$09007-49-2$$2NLM Chemicals$$aDNA 000051693 650_7 $$2WoSType$$aJ 000051693 7001_ $$0P:(DE-Juel1)132274$$aSutmann, G.$$b1$$uFZJ 000051693 773__ $$0PERI:(DE-600)1498203-1$$a10.1080/09553000400017614$$gVol. 80$$q80$$tInternational Journal of Radiation Biology$$v80$$x0955-3002$$y2004 000051693 8567_ $$uhttp://dx.doi.org/10.1080/09553000400017614 000051693 909CO $$ooai:juser.fz-juelich.de:51693$$pVDB 000051693 9131_ $$0G:(DE-Juel1)FUEK254$$bInformation$$kI03$$lWissenschaftliches Rechnen$$vBetrieb und Weiterentwicklung des Höchstleistungsrechners$$x0 000051693 9141_ $$aNachtrag$$y2004 000051693 915__ $$0StatID:(DE-HGF)0010$$2StatID$$aJCR/ISI refereed 000051693 915__ $$0StatID:(DE-HGF)0100$$2StatID$$aJCR 000051693 915__ $$0StatID:(DE-HGF)0111$$2StatID$$aWoS$$bScience Citation Index Expanded 000051693 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection 000051693 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bThomson Reuters Master Journal List 000051693 915__ $$0StatID:(DE-HGF)0300$$2StatID$$aDBCoverage$$bMedline 000051693 9201_ $$0I:(DE-Juel1)VDB62$$d31.12.2007$$gZAM$$kZAM$$lZentralinstitut für Angewandte Mathematik$$x0 000051693 9201_ $$0I:(DE-Juel1)VDB224$$gS$$kS$$lAbteilung Sicherheit und Strahlenschutz$$x1 000051693 970__ $$aVDB:(DE-Juel1)81158 000051693 980__ $$aVDB 000051693 980__ $$aConvertedRecord 000051693 980__ $$ajournal 000051693 980__ $$aI:(DE-Juel1)JSC-20090406 000051693 980__ $$aI:(DE-Juel1)VDB224 000051693 980__ $$aUNRESTRICTED 000051693 981__ $$aI:(DE-Juel1)JSC-20090406 000051693 981__ $$aI:(DE-Juel1)VDB224