Cysteine mutational studies provide insight into a thiol-based redox switch mechanism of metal and DNA binding in FurA from Anabaena sp. PCC 7120

Botello-Morte,L ; Pellicer,S. ; Contreras,L. M. ; Neira,J. L. ; Abian,O. (Universidad de Zaragoza) ; Velazquez-Campoy,A. (Universidad de Zaragoza) ; Peleato,M. L. (Universidad de Zaragoza) ; Fillat,M. F. (Universidad de Zaragoza) ; Bes,M. T. (Universidad de Zaragoza)

Resumen: Aims: The ferric uptake regulator (Fur) is the main transcriptional regulator of genes involved in iron homeostasis in most prokaryotes. FurA from Anabaena sp. PCC 7120 contains five cysteine residues, four of them arranged in two redox-active CXXC motifs. The protein needs not only metal but also reducing conditions to remain fully active in vitro. Through a mutational study of the cysteine residues present in FurA, we have investigated their involvement in metal and DNA binding. Results: Residue C101 that belongs to a conserved CXXC motif plays an essential role in both metal and DNA binding activities in vitro. Substitution of C101 by serine impairs DNA and metal binding abilities of FurA. Isothermal titration calorimetry measurements show that the redox state of C101 is responsible for the protein ability to coordinate the metal corepressor. Moreover, the redox state of C101 varies with the presence or absence of C104 or C133, suggesting that the environments of these cysteines are mutually interdependent. Innovation: We propose that C101 is part of a thiol/disulfide redox switch that determines FurA ability to bind the metal corepressor. Conclusion: This mechanism supports a novel feature of a Fur protein that emerges as a regulator, which connects the response to changes in the intracellular redox state and iron management in cyanobacteria.

Idioma: Inglés

DOI: 10.1089/ars.2014.6175

Año: 2016

Publicado en: ANTIOXIDANTS & REDOX SIGNALING 24, 4 (2016), 173-185
ISSN: 1523-0864

Factor impacto JCR: 6.337 (2016)

Categ. JCR: ENDOCRINOLOGY & METABOLISM rank: 13 / 138 = 0.094 (2016) - Q1 - T1
Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 34 / 287 = 0.118 (2016) - Q1 - T1

Factor impacto SCIMAGO: 2.896 - Biochemistry (Q1) - Cell Biology (Q1) - Physiology (Q1) - Medicine (miscellaneous) (Q1) - Molecular Biology (Q1) - Clinical Biochemistry (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA/B89
Financiación: info:eu-repo/grantAgreement/ES/FIS/PI10-00186
Financiación: info:eu-repo/grantAgreement/ES/ISCIII/CP07-00289
Financiación: info:eu-repo/grantAgreement/ES/MICINN/BFU2010-19451
Financiación: info:eu-repo/grantAgreement/ES/MINECO/BFU2012-31458
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CSD2008-00005
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2011-24393

Tipo y forma: Article (Published version)

Área (Departamento): Área Fisiología Vegetal (Dpto. Bioq.Biolog.Mol. Celular)
Área (Departamento): Área Bioquímica y Biolog.Mole. (Dpto. Bioq.Biolog.Mol. Celular)