Linked Life Data

11761322

Source:http://linkedlifedata.com/resource/pubmed/id/11761322

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-12-11
pubmed:abstractText
The midpoint potentials for the reduction of the cysteinyl-flavin adenine dinucleotide (FAD) in monoamine oxidases (MAO) A and B in the absence and presence of ligands have been determined. Both MAO A and MAO B can be reduced chemically in two steps, the first generating a semiquinone spectrum and the second the spectrum of fully reduced FAD, each of which requires two electron equivalents. The midpoint potentials for the oxidized/semiquinone and semiquinone/reduced couples were -159+/-4 mV and -262+/-3 mV for MAO A and -167+/-4 mV and -275+/-3 mV for MAO B. After modification with a thiol reagent, direct reduction from the oxidized to fully reduced form was observed with no semiquinone and without change in the overall midpoint potential. In the presence of substrate, no semiquinone was formed, but the midpoint potential for full reduction of the flavin was positively shifted by up to 500 mV, depending on the substrate. This shift in potential could permit a more thermodynamically favorable transfer of electrons from the amine substrates to oxygen. In contrast, stable products and inhibitors did not cause a shift in potential and did not prevent the formation of semiquinone.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1523-0864
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
723-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Substrates but not inhibitors alter the redox potentials of monoamine oxidases.
pubmed:affiliation
Department of Biochemistry and Biophysics, University of California San Francisco, 94143, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.