Linked Life Data

16730357

Source:http://linkedlifedata.com/resource/pubmed/id/16730357

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-7-3
pubmed:databankReference
pubmed:abstractText
It has been shown that the so-called scaffold proteins are vital in Fe-S cluster biosynthesis by providing an intermediate site for the assembly of Fe-S clusters. However, since no structural information on such scaffold proteins with bound Fe-S cluster intermediates is available, the structural basis of the core of Fe-S cluster biosynthesis remains poorly understood. Here we report the first Fe-S cluster-bound crystal structure of a scaffold protein, IscA, from Thermosynechococcus elongatus, which carries three strictly conserved cysteine residues. Surprisingly, one partially exposed [2Fe-2S] cluster is coordinated by two conformationally distinct IscA protomers, termed alpha and beta, with asymmetric cysteinyl ligation by Cys37, Cys101, Cys103 from alpha and Cys103 from beta. In the crystal, two alphabeta dimers form an unusual domain-swapped tetramer via central domains of beta protomers. Together with additional biochemical data supporting its physiologically relevant configuration, we propose that the unique asymmetric Fe-S cluster coordination and the resulting distinct conformational stabilities of the two IscA protomers are central to the function of IscA-type Fe-S cluster biosynthetic scaffold.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
360
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
117-32
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
The asymmetric IscA homodimer with an exposed [2Fe-2S] cluster suggests the structural basis of the Fe-S cluster biosynthetic scaffold.
pubmed:affiliation
Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't