Is the hypothiocyanite anion (OSCN)⁻ the major product in the peroxidase catalyzed oxidation of the thiocyanate anion (SCN)⁻? A joint experimental and theoretical study

dc.contributor.authorDua, S.
dc.contributor.authorMaclean, M.
dc.contributor.authorFitzgerald, M.
dc.contributor.authorMc Anoy, A.
dc.contributor.authorBowie, J.
dc.date.issued2006
dc.descriptionCopyright © 2006 American Chemical Society
dc.description.abstractThe hypothiocyanate anion (OSCN)(-) is reported to be a major product of the lactoperoxidase/H(2)O(2)/(SCN)(-) system, and this anion is proposed to have significant antimicrobial properties. The collision induced (CID) negative ion mass spectrum of "(OSCN)(-)" has been reported: there is a pronounced parent anion at m/z 74, together with fragment anions at m/z 58 (SCN)(-) and 26 (CN)(-). These fragment anions are consistent with structure (OSCN)(-). However there is also a lesser peak at m/z 42 (OCN(-) or CNO(-)) in this spectrum which is either formed by rearrangement of (OSCN)(-) or from an isomer of this anion. The current theoretical investigation of (OSCN)(-) and related isomers, together with the study of possible rearrangements of these anions, indicates that ground-state singlet (OSCN)(-) is a stable species and that isomerization is unlikely. The three anions (OSCN)(-), (SCNO)(-), and (SNCO)(-) have been synthesized (in the ion source of a mass spectrometer) by unequivocal routes, and their structures have been confirmed by a consideration of their collision induced (negative ion) and charge reversal (positive ion) mass spectra. The CID mass spectrum of (SCNO)(-) shows formation of m/z 42 (CNO(-)), but the corresponding spectra of (OSCN)(-) or (SNCO)(-) lack peaks at m/z 42. Combined theoretical and experimental data support earlier evidence that the hypothiocyanite anion is a major oxidation product of the H(2)O(2)/(SCN)(-) system. However, the formation of m/z 42 in the reported CID spectrum of "(OSCN)(-)" does not originate from (OSCN)(-) but from another isomer, possibly (SCNO)(-).
dc.description.statementofresponsibilitySuresh Dua, Micheal J. Maclean, Mark Fitzgerald, Andrew M. McAnoy, and John H. Bowie
dc.identifier.citationJournal of Physical Chemistry A, 2006; 110(14):4930-4936
dc.identifier.doi10.1021/jp058144t
dc.identifier.issn1089-5639
dc.identifier.issn1520-5215
dc.identifier.urihttp://hdl.handle.net/2440/23519
dc.language.isoen
dc.provenanceWeb Release Date: March 21, 2006
dc.publisherAmer Chemical Soc
dc.source.urihttps://doi.org/10.1021/jp058144t
dc.subjectThiocyanates
dc.subjectLactoperoxidase
dc.subjectAnti-Infective Agents
dc.subjectMolecular Structure
dc.subjectOxidation-Reduction
dc.subjectCatalysis
dc.subjectIsomerism
dc.subjectModels, Biological
dc.subjectMass Spectrometry
dc.titleIs the hypothiocyanite anion (OSCN)⁻ the major product in the peroxidase catalyzed oxidation of the thiocyanate anion (SCN)⁻? A joint experimental and theoretical study
dc.title.alternativeIs the hypothiocyanite anion (OSCN)(-) the major product in the peroxidase catalyzed oxidation of the thiocyanate anion (SCN)(-)? A joint experimental and theoretical study
dc.typeJournal article
pubs.publication-statusPublished

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