Linked Life Data

8108404

Source:http://linkedlifedata.com/resource/pubmed/id/8108404

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1994-3-22
pubmed:abstractText
The biological N2-fixation reaction is catalyzed by the enzyme nitrogenase. The metal cluster active site of this enzyme, the iron-molybdenum cofactor (FeMoco), can be studied either while bound within the MoFe protein component of nitrogenase or after it has been extracted into N-methylformamide. The two species are similar but not identical. For example, the addition of thiophenol or selenophenol to isolated FeMoco causes its rather broad S = 3/2 electron paramagnetic resonance signal to sharpen and more closely approach the signal exhibited by protein-bound FeMoco. The nature of this thiol/selenol binding site has been investigated by using Se-K edge extended x-ray absorption fine structure (EXAFS) to study selenophenol ligated to FeMoco, and the results are reported here. EXAFS data analysis at the ligand Se-K edge was performed with a set of software, GNXAS, that provides for direct calculation of the theoretical EXAFS signals and least-squares fits to the experimental data. Data analysis results show definitively that the selenol (and by inference thiol) binds to Fe at a distance of 2.4 A. In contrast, unacceptable fits are obtained with either Mo or S as the liganded atom (instead of Fe). These results provide quantitative details about an exchangeable thiol/selenol binding site on FeMoco in its isolated, solution state and establish an Fe atom as the site of this reaction. Furthermore, the utility of ligand-based EXAFS as a probe of coordination in polynuclear metal clusters is demonstrated.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-1529354, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-16593879, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-203578, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-2153269, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-2557830, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-2777773, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-2843534, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-3046607, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-3863780, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-410019, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-6243276, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-6320803, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-6930977, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-6960364, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-8430077, http://linkedlifedata.com/resource/pubmed/commentcorrection/8108404-8484118
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
91
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1290-3
pubmed:dateRevised
2010-9-13
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Selenol binds to iron in nitrogenase iron-molybdenum cofactor: an extended x-ray absorption fine structure study.
pubmed:affiliation
Department of Chemistry, Stanford University, CA 94305.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.