4-Thioflavins as active site probes of flavoproteins : general properties

Loading...
Thumbnail Image
Date
1984
Authors
Massey, Vincent
Claiborne, Al
Biemann, Monika
Editors
Contact
Journal ISSN
Electronic ISSN
ISBN
Bibliographical data
Publisher
Series
DOI (citable link)
ArXiv-ID
International patent number
EU project number
Project
Open Access publication
Collections
Restricted until
Title in another language
Research Projects
Organizational Units
Journal Issue
Publication type
Journal article
Publication status
Published in
Journal of Biological Chemistry ; 259 (1984), 15. - pp. 9667-9678
Abstract
4-Thioflavins (oxygen at position 4 replaced by sulfur) have been studied as potential active site probes of flavoproteins. They react readily with thiol reagents,with large spectral changes, which should be useful for testing the accessibility of the flavin 4-position in flavoproteins. They have an oxidation-reduction potential at pH 7 of -0.055 V, approximately 0.15 V higher than that of native flavins. The spectral characteristics in the fully reduced state show two clear absorption bands, dependent on the ionization state (pK = 4.5). The lowest energy band of the neutral dihydroflavin has a maximum at ~485 nm while that of the anion is ~425 nm. This should be useful in defining the ionization state of the reduced flavin in flavoproteins. The spectral characteristics of the semiquinoid forms of 4-thioflavins have been determined bound to the apoproteins of flavodoxin and D-amino acid oxidase. The neutral radical has an absorption maximum at 730 nm, while the anion radical has an unusually sharp peak at 415 nm. The reduced forms of 4-thioflavins, free and enzyme bound, react with O2 to regenerate oxidized 4-thioflavin. Reduced 4-thio-FAD p-hydroxybenzoate hydroxylase, however, in its reaction with 02, undergoes a substantial conversion to the native FAD-enzyme. 4-Thioflavins are unusually susceptible to attack by nucleophiles such as hydroxylamine and amines to form the respective 4-hydroxyimino- and 4-aminoflavins, offering the possibility of forming stable covalent flavin-protein linkages with suitably positioned protein residues. Thiols also react with 4-thioflavins, promoting their conversion to the normal (4- oxo) flavin coenzymes. Such reactivity has been found with the apoenzymes of glucose oxidase and lactate oxidase, providing evidence for a thiol residue in the active site of these enzymes.
Summary in another language
Subject (DDC)
570 Biosciences, Biology
Keywords
Conference
Review
undefined / . - undefined, undefined. - (undefined; undefined)
Cite This
ISO 690MASSEY, Vincent, Al CLAIBORNE, Monika BIEMANN, Sandro GHISLA, 1984. 4-Thioflavins as active site probes of flavoproteins : general properties. In: Journal of Biological Chemistry. 259(15), pp. 9667-9678
BibTex
@article{Massey19844Thio-8451,
  year={1984},
  title={4-Thioflavins as active site probes of flavoproteins : general properties},
  number={15},
  volume={259},
  journal={Journal of Biological Chemistry},
  pages={9667--9678},
  author={Massey, Vincent and Claiborne, Al and Biemann, Monika and Ghisla, Sandro}
}
RDF
<rdf:RDF
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:bibo="http://purl.org/ontology/bibo/"
    xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#"
    xmlns:foaf="http://xmlns.com/foaf/0.1/"
    xmlns:void="http://rdfs.org/ns/void#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > 
  <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/8451">
    <dcterms:bibliographicCitation>First publ. in: Journal of Biological Chemistry 259 (1984), 15, pp. 9667-9678</dcterms:bibliographicCitation>
    <bibo:uri rdf:resource="http://kops.uni-konstanz.de/handle/123456789/8451"/>
    <dc:creator>Biemann, Monika</dc:creator>
    <dcterms:issued>1984</dcterms:issued>
    <dcterms:abstract xml:lang="eng">4-Thioflavins (oxygen at position 4 replaced by sulfur) have been studied as potential active site probes of flavoproteins. They react readily with thiol reagents,with large spectral changes, which should be useful for testing the accessibility of the flavin 4-position in flavoproteins. They have an oxidation-reduction potential at pH 7 of -0.055 V, approximately 0.15 V higher than that of native flavins. The spectral characteristics in the fully reduced state show two clear absorption bands, dependent on the ionization state (pK = 4.5). The lowest energy band of the neutral dihydroflavin has a maximum at ~485 nm while that of the anion is ~425 nm. This should be useful in defining the ionization state of the reduced flavin in flavoproteins. The spectral characteristics of the semiquinoid forms of 4-thioflavins have been determined bound to the apoproteins of flavodoxin and D-amino acid oxidase. The neutral radical has an absorption maximum at 730 nm, while the anion radical has an unusually sharp peak at 415 nm. The reduced forms of 4-thioflavins, free and enzyme bound, react with O2 to regenerate oxidized 4-thioflavin. Reduced 4-thio-FAD p-hydroxybenzoate hydroxylase, however, in its reaction with 02, undergoes a substantial conversion to the native FAD-enzyme. 4-Thioflavins are unusually susceptible to attack by nucleophiles such as hydroxylamine and amines to form the respective 4-hydroxyimino- and 4-aminoflavins, offering the    possibility of forming stable covalent flavin-protein linkages with suitably positioned protein residues. Thiols also react with 4-thioflavins, promoting their conversion to the normal (4- oxo) flavin coenzymes. Such reactivity has been found with the apoenzymes of glucose oxidase and lactate oxidase, providing evidence for a thiol residue in the active site of these enzymes.</dcterms:abstract>
    <dc:contributor>Massey, Vincent</dc:contributor>
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
    <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/8451/1/4_Thioflavins_as_active_site_probes_of_flavoproteins.pdf"/>
    <dc:creator>Massey, Vincent</dc:creator>
    <dc:creator>Claiborne, Al</dc:creator>
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2011-03-24T17:43:47Z</dc:date>
    <dcterms:rights rdf:resource="http://creativecommons.org/licenses/by-nc-nd/2.0/"/>
    <dc:language>eng</dc:language>
    <dc:creator>Ghisla, Sandro</dc:creator>
    <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/8451/1/4_Thioflavins_as_active_site_probes_of_flavoproteins.pdf"/>
    <dc:format>application/pdf</dc:format>
    <dc:contributor>Claiborne, Al</dc:contributor>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2011-03-24T17:43:47Z</dcterms:available>
    <dcterms:title>4-Thioflavins as active site probes of flavoproteins : general properties</dcterms:title>
    <dc:contributor>Ghisla, Sandro</dc:contributor>
    <dc:contributor>Biemann, Monika</dc:contributor>
    <dc:rights>Attribution-NonCommercial-NoDerivs 2.0 Generic</dc:rights>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
  </rdf:Description>
</rdf:RDF>
Internal note
xmlui.Submission.submit.DescribeStep.inputForms.label.kops_note_fromSubmitter
Contact
URL of original publication
Test date of URL
Examination date of dissertation
Method of financing
Comment on publication
Alliance license
Corresponding Authors der Uni Konstanz vorhanden
International Co-Authors
Bibliography of Konstanz
No
Refereed