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EPR Characterization of Photosystem II from Different Domains of the Thylakoid Membrane.

Mamedov, Fikret LU ; Danielsson, Ravi LU ; Gadjieva, Rena LU ; Albertsson, Per-Åke LU and Styring, Stenbjörn LU (2008) In Biochemistry 47(12). p.3883-3891
Abstract
We report electron paramagnetic resonance (EPR) studies on photosystem II (PSII) from higher plants in five different domains of the thylakoid membrane prepared by sonication and two-phase partitioning. The domains studied were the grana core, the entire grana stack, the grana margins, the stroma lamellae and the purified stromal fraction, Y100. The electron transport properties of both donor and acceptor sides of PSII such as oxygen evolution, cofactors Y D, Q A, the CaMn 4-cluster, and Cytb 559 were investigated. The PSII content was estimated on the basis of oxidized Y D and Q A (-) Fe (2+) signal from the acceptor side vs Chl content (100% in the grana core fraction). It was found to be about 82% in the grana, 59% in the margins, 35%... (More)
We report electron paramagnetic resonance (EPR) studies on photosystem II (PSII) from higher plants in five different domains of the thylakoid membrane prepared by sonication and two-phase partitioning. The domains studied were the grana core, the entire grana stack, the grana margins, the stroma lamellae and the purified stromal fraction, Y100. The electron transport properties of both donor and acceptor sides of PSII such as oxygen evolution, cofactors Y D, Q A, the CaMn 4-cluster, and Cytb 559 were investigated. The PSII content was estimated on the basis of oxidized Y D and Q A (-) Fe (2+) signal from the acceptor side vs Chl content (100% in the grana core fraction). It was found to be about 82% in the grana, 59% in the margins, 35% in the stroma and 15% in the Y100 fraction. The most active PSII centers were found in the granal fractions as was estimated from the rates of electron transfer and the S 2 state multiline EPR signal. In the margin and stroma fractions the multiline signal was smaller (40 and 33%, respectively). The S 2 state multiline could not be induced in the Y100 fraction. In addition, the oxidized LP Cytb 559 prevailed in the stromal fractions while the HP form dominated in the grana core. The margins and entire grana fractions have Cytb 559 in both potential forms. These data together with previous analyses indicate that the sequence of activation of the PSII properties can be represented as: PSII content > oxygen evolution > reduced Cytb 559 > dimerization of PSII centers in all fractions of the thylakoid membrane with the gradual increase from stromal fractions via margin to the grana core fraction. The results further support the existence of a PSII activity gradient which reflects lateral movement and photoactivation of PSII centers in the thylakoid membrane. The possible role of the PSII redox components in this process is discussed. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Biochemistry
volume
47
issue
12
pages
3883 - 3891
publisher
The American Chemical Society
external identifiers
  • pmid:18303856
  • wos:000254127900031
  • scopus:41149105266
ISSN
0006-2960
DOI
10.1021/bi701913k
language
English
LU publication?
yes
id
27404a53-5636-48e5-a1f2-40ab7ae18faf (old id 1041452)
date added to LUP
2008-03-25 15:47:45
date last changed
2017-04-09 03:35:37
@article{27404a53-5636-48e5-a1f2-40ab7ae18faf,
  abstract     = {We report electron paramagnetic resonance (EPR) studies on photosystem II (PSII) from higher plants in five different domains of the thylakoid membrane prepared by sonication and two-phase partitioning. The domains studied were the grana core, the entire grana stack, the grana margins, the stroma lamellae and the purified stromal fraction, Y100. The electron transport properties of both donor and acceptor sides of PSII such as oxygen evolution, cofactors Y D, Q A, the CaMn 4-cluster, and Cytb 559 were investigated. The PSII content was estimated on the basis of oxidized Y D and Q A (-) Fe (2+) signal from the acceptor side vs Chl content (100% in the grana core fraction). It was found to be about 82% in the grana, 59% in the margins, 35% in the stroma and 15% in the Y100 fraction. The most active PSII centers were found in the granal fractions as was estimated from the rates of electron transfer and the S 2 state multiline EPR signal. In the margin and stroma fractions the multiline signal was smaller (40 and 33%, respectively). The S 2 state multiline could not be induced in the Y100 fraction. In addition, the oxidized LP Cytb 559 prevailed in the stromal fractions while the HP form dominated in the grana core. The margins and entire grana fractions have Cytb 559 in both potential forms. These data together with previous analyses indicate that the sequence of activation of the PSII properties can be represented as: PSII content > oxygen evolution > reduced Cytb 559 > dimerization of PSII centers in all fractions of the thylakoid membrane with the gradual increase from stromal fractions via margin to the grana core fraction. The results further support the existence of a PSII activity gradient which reflects lateral movement and photoactivation of PSII centers in the thylakoid membrane. The possible role of the PSII redox components in this process is discussed.},
  author       = {Mamedov, Fikret and Danielsson, Ravi and Gadjieva, Rena and Albertsson, Per-Åke and Styring, Stenbjörn},
  issn         = {0006-2960},
  language     = {eng},
  number       = {12},
  pages        = {3883--3891},
  publisher    = {The American Chemical Society},
  series       = {Biochemistry},
  title        = {EPR Characterization of Photosystem II from Different Domains of the Thylakoid Membrane.},
  url          = {http://dx.doi.org/10.1021/bi701913k},
  volume       = {47},
  year         = {2008},
}