DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Chloride facilitates Mn(III) formation during photoassembly of the Photosystem II oxygen-evolving complex

Journal Article · · Photosynthesis Research

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. Here, when combined with pH studies, we conclude that the first Mn2+ oxidation event in OEC assembly requires a deprotonation that is facilitated by chloride.

Research Organization:
Louisiana State University, Baton Rouge, LA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB); Herman Frasch Fund for Chemical Research
Grant/Contract Number:
SC0020119
OSTI ID:
2283330
Alternate ID(s):
OSTI ID: 1909567
Journal Information:
Photosynthesis Research, Journal Name: Photosynthesis Research Journal Issue: 3 Vol. 152; ISSN 0166-8595
Publisher:
SpringerCopyright Statement
Country of Publication:
United States
Language:
English

References (27)

Photoactivation: The Light-Driven Assembly of the Water Oxidation Complex of Photosystem II journal May 2016
Progress Toward a Molecular Mechanism of Water Oxidation in Photosystem II journal May 2017
The Structure of Photosystem II and the Mechanism of Water Oxidation in Photosynthesis journal April 2015
Calcium Modulates the Photo-assembly of Photosystem II (Mn)4-Clusters by Preventing Ligation of Nonfunctional High-Valency States of Manganese journal October 1995
The role of Ca 2+ and protein scaffolding in the formation of nature’s water oxidizing complex journal October 2020
Chloride Regulation of Enzyme Turnover: Application to the Role of Chloride in Photosystem II journal April 2011
EasySpin, a comprehensive software package for spectral simulation and analysis in EPR journal January 2006
Bicarbonate-induced redox tuning in Photosystem II for regulation and protection journal October 2016
Spectroscopic Evidence for Ca 2+ Involvement in the Assembly of the Mn 4 Ca Cluster in the Photosynthetic Water-Oxidizing Complex journal October 2006
Enhancement by chloride ions of photoactivation of oxygen evolution in manganese-depleted photosystem II membranes journal June 1991
Cryo-EM Structure of Monomeric Photosystem II from Synechocystis sp. PCC 6803 Lacking the Water-Oxidation Complex journal October 2020
Crystal structure of oxygen-evolving photosystem II at a resolution of 1.9 Å journal April 2011
Dual-Mode EPR Detects the Initial Intermediate in Photoassembly of the Photosystem II Mn Cluster:  The Influence of Amino Acid Residue 170 of the D1 Polypeptide on Mn Coordination journal April 2000
The roles of the extrinsic subunits in Photosystem II as revealed by EPR journal June 1985
Rapid-Scan Time-Resolved ATR-FTIR Study on the Photoassembly of the Water-Oxidizing Mn 4 CaO 5 Cluster in Photosystem II journal April 2021
Manganese and calcium requirements for reconstitution of oxygen-evolution activity in manganese-depleted photosystem II membranes journal October 1989
Structural insights into photosystem II assembly journal April 2021
Photoactivation of the manganese catalyst of O2 evolution. II. A two-quantum mechanism journal November 1971
Photoassembly of the water-oxidizing complex in photosystem II journal February 2008
Bicarbonate Coordinates to Mn3+ during Photo-Assembly of the Catalytic Mn4Ca Core of Photosynthetic Water Oxidation: EPR Characterization journal November 2009
Dry-Ice Bath Based on Ethylene Glycol Mixtures journal May 2000
Electron-transfer events leading to reconstitution of oxygen-evolution activity in manganese-depleted photosystem II membranes journal February 1990
The Psb27 Protein Facilitates Manganese Cluster Assembly in Photosystem II journal December 2007
Mn(III) species formed by the multi-copper oxidase MnxG investigated by electron paramagnetic resonance spectroscopy journal July 2018
Photosystem II oxygen-evolving complex photoassembly displays an inverse H/D solvent isotope effect under chloride-limiting conditions journal September 2019
How acidic is the lumen? journal May 1999
The Manganese-Stabilizing Protein of Photosystem II Modifies the in Vivo Deactivation and Photoactivation Kinetics of the H 2 O Oxidation Complex in Synechocystis sp. PCC6803 journal January 1996