Linked Life Data

16402206

Source:http://linkedlifedata.com/resource/pubmed/id/16402206

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-2-10
pubmed:abstractText
FdVI from Rhodobacter capsulatus is structurally related to a group of [2Fe-2S] ferredoxins involved in iron-sulfur cluster biosynthesis. Comparative genomics suggested that FdVI and orthologs found in alpha-Proteobacteria are involved in this process. Here, the crystal structure of FdVI has been determined for both the oxidized and the reduced protein. The [2Fe-2S] cluster lies 6 A below the protein surface in a hydrophobic pocket without access to the solvent. This particular cluster environment might explain why the FdVI midpoint redox potential (-306 mV at pH 8.0) did not show temperature or ionic strength dependence. Besides the four cysteines that bind the cluster, FdVI features an extra cysteine which is located close to the S1 atom of the cluster and is oriented in a position such that its thiol group points towards the solvent. Upon reduction, the general fold of the polypeptide chain was almost unchanged. The [2Fe-2S] cluster underwent a conformational change from a planar to a distorted lozenge. In the vicinity of the cluster, the side chain of Met24 was rotated by 180 degrees , bringing its S atom within hydrogen-bonding distance of the S2 atom of the cluster. The reduced molecule also featured a higher content of bound water molecules, and more extensive hydrogen-bonding networks compared with the oxidized molecule. The unique conformational changes observed in FdVI upon reduction are discussed in the light of structural studies performed on related ferredoxins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0949-8257
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
235-46
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Structure of a [2Fe-2S] ferredoxin from Rhodobacter capsulatus likely involved in Fe-S cluster biogenesis and conformational changes observed upon reduction.
pubmed:affiliation
European Synchrotron Radiation Facility, BP 220, 38054 Grenoble Cedex 9, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural