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Water in Photosystem II: structural, functional and mechanistic considerations
1Photochemistry & Molecular Science, Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 751 20 Uppsala, Sweden.
Biochimica Et Biophysica Acta
|August 28, 2013
Summary
Water is crucial for Photosystem II (PSII) function, acting as a substrate and facilitating proton transport. Viewing water as integral to proteins, not just a solvent, offers new research avenues.
Area of Science:
- Biochemistry
- Structural Biology
- Photosynthesis Research
Background:
- Photosystem II (PSII) is a vital enzyme for water oxidation.
- Water's role in PSII extends beyond substrate to proton transport and cofactor stabilization.
- Recent crystal structures offer insights into water molecule localization and function within PSII.
Purpose of the Study:
- To review current research on the mechanistic significance of water in Photosystem II.
- To analyze the role of water molecules and transport pathways in PSII function.
- To draw parallels with water's role in other biological systems like aquaporins.
Main Methods:
- Analysis of recent crystal structural data of Photosystem II.
- Investigation of water channels and pathways within the PSII protein complex.
- Comparative analysis of water's role in aquaporin, bacteriorhodopsin, and cytochrome P450.
Main Results:
- Detailed understanding of water molecule locations and potential functions in PSII.
- Identification of key channels and pathways facilitating water and proton movement.
- Emerging clarity on the mechanistic importance of water for PSII's catalytic activity.
Conclusions:
- Water is essential for Photosystem II's substrate transport, proton movement, and overall function.
- Water should be considered an integral component of proteins, not merely a solvent.
- Understanding water's role in PSII has potential applications for future research and bio-inspired technologies.
Keywords:
AQPBRCCYPChannelFTIRFourier transform infraredGrotthussKIELCSMDMSMDOxygenP(680)PBDPSIIPhotosystem IIProtonQ(A)Q(B)Tyr(D)Tyr(Z)WTWateraquaporinbRbacterial reaction centerbacteriorhodopsincytochrome P450kinetic isotope effectlarge channel systemmolecular dynamicsmultiple steered molecular dynamicsphotothermal beam deflectionthe D1-Tyr161 residue in Photosystem IIthe D2-Tyr160 residue in Photosystem IIthe first quinone acceptor in Photosystem II/bacterial reaction centerthe primary donor in Photosystem IIthe second quinone acceptor in Photosystem II/bacterial reaction centerwild-type
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