Linked Life Data

17330815

Source:http://linkedlifedata.com/resource/pubmed/id/17330815

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-3-19
pubmed:abstractText
The binding of NO to iron is involved in the biological function of many heme proteins. Contrary to ligands like CO and O(2), which only bind to ferrous (Fe(II)) iron, NO binds to both ferrous and ferric (Fe(III)) iron. In a particular protein, the natural oxidation state can therefore be expected to be tailored to the required function. Herein, we present an ab initio potential-energy surface for ferric iron interacting with NO. This potential-energy surface exhibits three minima corresponding to eta(1)-NO coordination (the global minimum), eta(1)-ON coordination and eta(2) coordination. This contrasts with the potential-energy surface for Fe(II)-NO, which exhibits only two minima (the eta(2) coordination mode for Fe(II) is a transition state, not a minimum). In addition, the binding energies of NO are substantially larger for Fe(III) than for Fe(II). We have performed molecular dynamics simulations for NO bound to ferric myoglobin (Mb(III)) and compare these with results obtained for Mb(II). Over the duration of our simulations (1.5 ns), all three binding modes are found to be stable at 200 K and transiently stable at 300 K, with eventual transformation to the eta(1)-NO global-minimum conformation. We discuss the implication of these results related to studies of rebinding processes in myoglobin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1439-4235
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
527-36
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Ferric and ferrous iron in nitroso-myoglobin: computer simulations of stable and metastable States and their infrared spectra.
pubmed:affiliation
Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't