Fast reversible electron transfer for photosynthetic reaction center from wild type Rhodobacter sphaeroides re-constituted in polycation sandwiched monolayer film

Citation
Jl. Kong et al., Fast reversible electron transfer for photosynthetic reaction center from wild type Rhodobacter sphaeroides re-constituted in polycation sandwiched monolayer film, BIOELECTR B, 48(1), 1999, pp. 101-107
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOELECTROCHEMISTRY AND BIOENERGETICS
ISSN journal
0302-4598 → ACNP
Volume
48
Issue
1
Year of publication
1999
Pages
101 - 107
Database
ISI
SICI code
0302-4598(199902)48:1<101:FRETFP>2.0.ZU;2-P
Abstract
Direct reversible electron transfer for photosynthetic reaction center from wild type Rhodobacter sphaeroides re-constituted in polycation sandwiched monolayer film was observed in this work. The redox potential E-0,E- = 0.46 V vs. NHE for first primary donor redox couple P/P+ was accurately measure d from reversible CV or SWV peaks, which were quite close to those obtained from optic redox titration method. Reaction center (RC) in film was found re-constituted in such an ordered way that the orientation of RC favored th e electron transfer in Nm. Thus, the protein electroactivity seems to be tu rned on in this artificial biomimic thin film. Furthermore, RC in the film features a photo-induced redox-peak fluctuation, suggesting an intact and f unctional state for RC in such film. Redox peaks were also found dependent of pH, implying a proton-coupled electron transfer occurring in film. Charg e recombination was observed accompanied with change of electrochemical dri ving force. Electrochemical model assuming several classes of electroactive sites in the films on the electrode with a dispersion of standard potentia ls successfully fits SWV experimental data at different pulse height and fr equency. (C) 1999 Elsevier Science S.A. All rights reserved.