Linked Life Data

12773155

Source:http://linkedlifedata.com/resource/pubmed/id/12773155

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 3
pubmed:dateCreated
2003-5-29
pubmed:abstractText
Cytochrome c ' (cyt c ') is found in the periplasmic space of denitrifying bacteria where it is thought to mediate the transfer of NO between the nitrogen-cycle enzymes dissimilatory nitrite reductase and nitric oxide reductase. It contains a 5-coordinate (5c) His-ligated haem that shares spectroscopic and ligand-binding properties with the haem group in the sensory domain of soluble guanylate cyclase (sGC). The latter is an extremely important enzyme involved in the control of vasodilation and blood clotting. Curiously, the enzyme is activated up to 200-fold by the binding of NO to the haem, whereas the binding of CO gives rise to only a mild stimulation of activity. Through X-ray crystallography we have studied NO and CO binding to cyt c '. CO binds to the distal face to give a 6-coordinate (6c) adduct. By contrast, NO binding gives rise to a 5c adduct through the displacement of the proximal His, to give a novel and unexpected proximal binding mode for NO. These results are also supported by a range of spectroscopies. In the absence of a crystal structure for sGC we propose that cyt c ' provides a structural model for the haem domain of this enzyme and thereby helps to explain the differential effects of NO and CO on its activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0300-5127
pubmed:author
pubmed:issnType
Print
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
553-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
A two-faced molecule offers NO explanation: the proximal binding of nitric oxide to haem.
pubmed:affiliation
Department of Biological Chemistry, John Innes Centre, Norwich NR4 7UH, UK. david.lawson@bbsrc.ac.uk
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review, Research Support, Non-U.S. Gov't