A single residue controls electron transfer gating in photosynthetic reaction centers

0474015 - MBÚ 2018 RIV GB eng J - Článek v odborném periodiku
Shlyk, O. - Samish, I. - Matěnová, M. - Dulebo, A. - Poláková, H. - Kaftan, David - Scherz, A.
A single residue controls electron transfer gating in photosynthetic reaction centers.
Scientific Reports. Roč. 7, MAR 16 (2017), s. 1-13, č. článku 44580. ISSN 2045-2322. E-ISSN 2045-2322
Grant CEP: GA ČR GA15-00703S; GA MŠMT(CZ) LO1416
Institucionální podpora: RVO:61388971
Klíčová slova: BACTERIAL REACTION CENTERS * INDUCED STRUCTURAL-CHANGES * ATOMIC-FORCE MICROSCOPE
Obor OECD: Microbiology
Impakt faktor: 4.122, rok: 2017

Interquinone Q(A) -> Q(B) electron-transfer (ET) in isolated photosystem II reaction centers (PSII- RC) is protein-gated. The temperature-dependent gating frequency 'k' is described by the Eyring equation till levelling off at T >= 240 degrees K. Although central to photosynthesis, the gating mechanism has not been resolved and due to experimental limitations, could not be explored in vivo. Here we mimic the temperature dependency of 'k' by enlarging VD1-208, the volume of a single residue at the crossing point of the D1 and D2 PSII- RC subunits in Synechocystis 6803 whole cells. By controlling the interactions of the D1/D2 subunits, VD1-208 (or 1/T) determines the frequency of attaining an ET-active conformation. Decelerated ET, impaired photosynthesis, D1 repair rate and overall cell physiology upon increasing VD1- 208 to above 130 angstrom(3), rationalize the > 99% conservation of small residues at D1- 208 and its homologous motif in non-oxygenic bacteria. The experimental means and resolved mechanism are relevant for numerous transmembrane protein-gated reactions.
Trvalý link: http://hdl.handle.net/11104/0271113