Proton uptake upon anaerobic reduction of the Paracoccus denitrificans cytochrome c oxidase: a kinetic investigation of the K354M and D124N mutants. (Articolo in rivista)

Type

• Prodotto della ricerca (Classe)
• Articolo in rivista (Classe)

Label

• Proton uptake upon anaerobic reduction of the Paracoccus denitrificans cytochrome c oxidase: a kinetic investigation of the K354M and D124N mutants. (Articolo in rivista) (literal)

Anno

• 2004-01-01T00:00:00+01:00 (literal)

Alternative label

• Forte E; Scandurra FM; Richter OM; D'Itri E; Sarti P; Brunori M; Ludwig B; Giuffrè A. (2004)
  Proton uptake upon anaerobic reduction of the Paracoccus denitrificans cytochrome c oxidase: a kinetic investigation of the K354M and D124N mutants.
  in Biochemistry (Easton)
  (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

• Forte E; Scandurra FM; Richter OM; D'Itri E; Sarti P; Brunori M; Ludwig B; Giuffrè A. (literal)

Pagina inizio

• 2957 (literal)

Pagina fine

• 2963 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

• 43 (literal)

Rivista

• Biochemistry (Rivista)

Note

• ISI Web of Science (WOS) (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

• Department of Biochemical Sciences and CNR Institute of Molecular Biology and Pathology, UniVersity of Rome \"La Sapienza\", I-00185 Rome, Italy, and Institute of Biochemistry, Molecular Genetics, UniVersity of Frankfurt, Biozentrum, D-60439 Frankfurt, Germany. (literal)

Titolo

• Proton uptake upon anaerobic reduction of the Paracoccus denitrificans cytochrome c oxidase: a kinetic investigation of the K354M and D124N mutants. (literal)

Abstract

• The kinetics and stoichiometry of the redox-linked protonation of the soluble Paracoccus denitrificans cytochrome c oxidase were investigated at pH ) 7.2-7.5 by multiwavelength stopped-flow spectroscopy, using the pH indicator phenol red. We compared the wild-type enzyme with the K354M and the D124N subunit I mutants, in which the K- and D-proton-conducting pathways are impaired, respectively. Upon anaerobic reduction by Ru-II hexamine, the wild-type enzyme binds 3.3 +/- 0.6 H+/aa3, i.e., approximately 1 H+ in excess over beef heart oxidase under similar conditions and the D124N mutant 3.2 +/- 0.5 H+/aa3. In contrast, in the K354M mutant, in which the reduction of heme a3-CuB is severely impaired, ?0.8 H+ is promptly bound synchronously with the reduction of heme a, followed by a much slower protonation associated with the retarded reduction of the heme a3-CuB site. These results indicate that complete reduction of heme a (and CuA) is coupled to the uptake of ?0.8 H+, which is independent of both H+-pathways, whereas the subsequent reduction of the heme a3-CuB site is associated with the uptake of ?2.5 H+ transferred (at least partially) through the K-pathway. On the basis of these results, the possible involvement of the D-pathway in the redox-linked protonation of cytochrome c oxidase is discussed. (literal)

Prodotto di

• Biologia strutturale e bioinformatica: struttura-funzione, dinamica e riconoscimento in proteine (SV.P14.008.001) (Modulo)
• Institute of molecular biology and pathology (IBPM) (Istituto)

Autore CNR

• ALESSANDRO GIUFFRE' (Unità di personale interno)
• MAURIZIO BRUNORI (Persona)

Incoming links:

Prodotto

• Institute of molecular biology and pathology (IBPM) (Istituto)
• Biologia strutturale e bioinformatica: struttura-funzione, dinamica e riconoscimento in proteine (SV.P14.008.001) (Modulo)

Autore CNR di

• ALESSANDRO GIUFFRE' (Unità di personale interno)
• MAURIZIO BRUNORI (Persona)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#rivistaDi

• Biochemistry (Rivista)