Ferredoxin competes with bacterial frataxin in binding to the desulfurase IscS.
J Biol Chem
; 288(34): 24777-87, 2013 Aug 23.
Article
em En
| MEDLINE
| ID: mdl-23839945
ABSTRACT
The bacterial iron-sulfur cluster (isc) operon is an essential machine that is highly conserved from bacteria to primates and responsible for iron-sulfur cluster biogenesis. Among its components are the genes for the desulfurase IscS that provides sulfur for cluster formation, and a specialized ferredoxin (Fdx) whose role is still unknown. Preliminary evidence suggests that IscS and Fdx interact but nothing is known about the binding site and the role of the interaction. Here, we have characterized the interaction using a combination of biophysical tools and mutagenesis. By modeling the Fdx·IscS complex based on experimental restraints we show that Fdx competes for the binding site of CyaY, the bacterial ortholog of frataxin and sits in a cavity close to the enzyme active site. By in vivo mutagenesis in bacteria we prove the importance of the surface of interaction for cluster formation. Our data provide the first structural insights into the role of Fdx in cluster assembly.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Liases de Carbono-Enxofre
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Modelos Moleculares
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Proteínas de Escherichia coli
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Proteínas de Ligação ao Ferro
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Escherichia coli
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Ferredoxinas
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Reino Unido