Femtosecond UV studies of the electronic relaxation processes in Cytochrome c

We report on an experimental study with UV and visible ultrafast time-gated emission and transient absorption of the early photodynamics of horse heart Cytochrome c in both ferric and ferrous redox states. A clear separation in time and energy of tryptophan and haem emission is observed. Excitation...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:The journal of physical chemistry. B Jg. 115; H. 46; S. 13723
Hauptverfasser: Bräm, Olivier, Consani, Cristina, Cannizzo, Andrea, Chergui, Majed
Format: Journal Article
Sprache:Englisch
Veröffentlicht: United States 24.11.2011
Schlagworte:
Animals
Cytochromes c - chemistry
Electrons
Energy Transfer
Heme - chemistry
Horses
Oxidation-Reduction
Spectrophotometry, Ultraviolet
Time Factors
Tryptophan - chemistry
ISSN:1520-5207, 1520-5207
Online-Zugang:Weitere Angaben
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:We report on an experimental study with UV and visible ultrafast time-gated emission and transient absorption of the early photodynamics of horse heart Cytochrome c in both ferric and ferrous redox states. A clear separation in time and energy of tryptophan and haem emission is observed. Excitation of the haem via resonant energy transfer from the tryptophan residue is observed in the subsequent haem electronic relaxation. Different Trp-haem energy transfer time constants of the ferrous and ferric forms are obtained. An almost instantaneous relaxation to the lowest singlet excited state (corresponding to the so-called Q band) characterizes the earliest electronic dynamics of the haem, independent of excitation energy, while dark intermediate states govern the ground-state recovery. The information gathered in these two experiments and in the literature allows us to propose a simple scheme for the electronic relaxation leading to ligand dissociation.
Bibliographie:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:1520-5207
1520-5207
DOI:10.1021/jp207615u