Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-6-5
pubmed:abstractText
The catalytic Zn(II) ion of horse liver alcohol dehydrogenase (EE isozyme) was replaced by Fe(II), providing a novel iron protein with the unusual coordination of Fe(II) to two cysteines residues, one histine residue and water. The electronic structure of iron in this system was characterized by Mössbauer spectroscopy at various temperatures as well as applied magnetic fields and analysed in terms of the spin Hamiltonian formalism. The novelty we found is an unusually weak spin coupling (/J/ less than 0.1 cm-1) of a paramagnet (S = 1) with iron (S = 2). From EPR and biochemical studies we conclude that the corresponding chemical species is triplet oxygen (O2). The quantitative determination of the coupling energy was possible utilizing the competition between Zeemann interaction and spin coupling at weak magnetic fields and low temperature. Oxidation experiments followed by Mössbauer spectroscopy showed that the spin-coupled system is an outer-sphere Fe(II) . (O2)aq complex occurring as an intermediate during a Fe(II)-catalyzed dioxygen activation. We observed two additional Fe(II) species after treatment with O2 and dithionite. The spin Hamiltonian parameters of iron in the coupled system are presented. The results are compared with those of iron in other non-heme iron proteins.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
180
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
111-21
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Fe(II)-substituted horse liver alcohol dehydrogenase, a model for non-heme iron enzymes. Various states of iron-dioxygen interaction investigated by Mössbauer and EPR spectroscopy.
pubmed:affiliation
Institut für Physik, Medizinische Universität, Lübeck, Federal Republic of Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't