Journal
PHOTOSYNTHESIS RESEARCH
Volume 152, Issue 3, Pages 283-288Publisher
SPRINGER
DOI: 10.1007/s11120-021-00886-4
Keywords
Photosystem II; Oxygen-evolving complex; Assembly; Electron paramagnetic resonance spectroscopy
Categories
Funding
- U.S. Department of Energy, Office of Science, Office of Basic Energy Science, Division of Chemical Sciences, Geosciences, and Biosciences, Photosynthetic Systems [DE-SC0020119]
- Herman Frasch Fund for Chemical Research [822-HF17]
- Louisiana Board of Regents Support Fund
- U.S. Department of Energy (DOE) [DE-SC0020119] Funding Source: U.S. Department of Energy (DOE)
Ask authors/readers for more resources
The study found that the first Mn2+ oxidation event in the assembly of the oxygen-evolving complex in Photosystem II requires chloride-facilitated deprotonation. This process is dependent on the presence of calcium at physiologically relevant pH values.
The Mn4Ca oxygen-evolving complex (OEC) in Photosystem II (PSII) is assembled in situ from free Mn2+, Ca2+, and water. In an early light-driven step, Mn2+ in a protein high-affinity site is oxidized to Mn3+. Using dual-mode electron paramagnetic resonance spectroscopy, we observed that Mn3+ accumulation increases as chloride concentration increases in spinach PSII membranes depleted of all extrinsic subunits. At physiologically relevant pH values, this effect requires the presence of calcium. When combined with pH studies, we conclude that the first Mn2+ oxidation event in OEC assembly requires a deprotonation that is facilitated by chloride.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available
Share Paper
