Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
1989-10-25
pubmed:abstractText
19F NMR and x-ray absorption experiments have been performed with both the isolated FeMo cofactor and the MoFe protein of nitrogenase in search of direct evidence for substrate or inhibitor binding. Using 19F NMR as a probe and p-CF3C6H4S- as the receptor ligand, the data show that the nitrogenase inhibitors CN- and CH3NC bind to the isolated FeMo cofactor-RFS- complex in N-methylformamide with a finite formation constant. Their binding increases the electronic relaxation time of the complex and increases the life-time of the FeMo cofactor-p-CF3C6H4S- bond, Parallel molybdenum K edge and extended x-ray absorption fine structure experiments show that CH3NC does not bind to molybdenum. Although CO and N3- both relieve CN- and CH3NC inhibition of electron flow through nitrogenase, unlike the latter, they do not appear to bind to isolated FeMo cofactor. In experiments with the dithionite-reduced MoFe protein, we did not detect any changes in the molybdenum K edge or extended x-ray absorption fine structure spectra upon addition of CO, N2, C2H2, NaCN, CH3NC, or azide demonstrating that either these substrates and inhibitors do not bind to molybdenum or that the FeMo cofactor site of nitrogenase is inaccessible to substrate binding except under turnover conditions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
264
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15967-74
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Cyanide and methylisocyanide binding to the isolated iron-molybdenum cofactor of nitrogenase.
pubmed:affiliation
Department of Molecular Biology and Biochemistry, University of California, Irvine 92717.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.