Long-Range Electron Tunneling from the Primary to Secondary Quinones in Photosystem II Enhanced by Hydrogen Bonds with a Nonheme Fe Complex

Author(s):  
Hiroyuki Tamura ◽  
Keisuke Saito ◽  
Hiroshi Ishikita
Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 371
Author(s):  
Koua

The Mn4CaO5 cluster site in the oxygen-evolving complex (OEC) of photosystem II (PSII) undergoes structural perturbations, such as those induced by Ca2+/Sr2+ exchanges or Ca/Mn removal. These changes have been known to induce long-range positive shifts (between +30 and +150 mV) in the redox potential of the primary quinone electron acceptor plastoquinone A (QA), which is located 40 Å from the OEC. To further investigate these effects, we reanalyzed the crystal structure of Sr-PSII resolved at 2.1 Å and compared it with the native Ca-PSII resolved at 1.9 Å. Here, we focus on the acceptor site and report the possible long-range interactions between the donor, Mn4Ca(Sr)O5 cluster, and acceptor sites.


1982 ◽  
Vol 104 (9) ◽  
pp. 2596-2599 ◽  
Author(s):  
C. A. Stein ◽  
Nita A. Lewis ◽  
Gunther Seitz

2020 ◽  
Vol 117 (26) ◽  
pp. 15354-15362 ◽  
Author(s):  
Ricarda Höhner ◽  
Mathias Pribil ◽  
Miroslava Herbstová ◽  
Laura Susanna Lopez ◽  
Hans-Henning Kunz ◽  
...  

In photosynthetic electron transport, large multiprotein complexes are connected by small diffusible electron carriers, the mobility of which is challenged by macromolecular crowding. For thylakoid membranes of higher plants, a long-standing question has been which of the two mobile electron carriers, plastoquinone or plastocyanin, mediates electron transport from stacked grana thylakoids where photosystem II (PSII) is localized to distant unstacked regions of the thylakoids that harbor PSI. Here, we confirm that plastocyanin is the long-range electron carrier by employing mutants with different grana diameters. Furthermore, our results explain why higher plants have a narrow range of grana diameters since a larger diffusion distance for plastocyanin would jeopardize the efficiency of electron transport. In the light of recent findings that the lumen of thylakoids, which forms the diffusion space of plastocyanin, undergoes dynamic swelling/shrinkage, this study demonstrates that plastocyanin diffusion is a crucial regulatory element of plant photosynthetic electron transport.


2013 ◽  
Vol 47 (1) ◽  
pp. 63-65 ◽  
Author(s):  
A. A. Andronov ◽  
E. P. Dodin ◽  
D. I. Zinchenko ◽  
Yu. N. Nozdrin

2007 ◽  
pp. 831-833 ◽  
Author(s):  
David Rodríguez-Lucena ◽  
Juan M. Benito ◽  
Carmen Ortiz Mellet ◽  
José M. García Fernández
Keyword(s):  

2021 ◽  
Vol 8 (1) ◽  
pp. 2
Author(s):  
Cai-Ming Liu ◽  
You Song

Ferromagnetic coupling exists in an uneven chain-like copper(II) complex with both end-on azido and syn-syn carboxylato bridges, (Cu3(L)2(N3)4(H2O)3)n (1, HL = 6-hydroxynicotinic acid). It is the first example of one-dimensional (1D) chain-like copper(II) coordination polymer showing both metamagnetic behavior and long-range magnetic ordering (Tc = 6.7 K), thanks to the interchain hydrogen bonds, which make a three-dimensional (3D) supramolecular array of the entire molecular structure and mediate the interchain antiferromagnetic interaction.


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