scholarly journals Stability of organic compounds on the oxygen-evolving center of photosystem II and manganese oxide water oxidation catalysts

2016 ◽  
Vol 52 (95) ◽  
pp. 13760-13763 ◽  
Author(s):  
Toru Hayashi ◽  
Akira Yamaguchi ◽  
Kazuhito Hashimoto ◽  
Ryuhei Nakamura
Keyword(s):  
Photosystem Ii ◽  
Manganese Oxide ◽  
Organic Compounds ◽  
Water Oxidation ◽  
Carboxyl Groups ◽  
Oxidation Catalysts ◽  
Oxygen Evolving ◽  
Mn Oxides

Carboxyl groups, abundant residues around the Mn4cluster of photosystem II, stably facilitated electrochemical water oxidation by Mn oxides.

scholarly journals Simulation of the isotropic EXAFS spectra for the S2 and S3 structures of the oxygen evolving complex in photosystem II

2015 ◽  
Vol 112 (13) ◽  
pp. 3979-3984 ◽  
Author(s):  
Xichen Li ◽  
Per E. M. Siegbahn ◽  
Ulf Ryde
Keyword(s):  
Photosystem Ii ◽  
Water Oxidation ◽  
Density Functional ◽  
Structural Changes ◽  
Complete Agreement ◽  
Oxygen Evolving Complex ◽  
Chemical Modeling ◽  
Oxygen Evolving ◽  
High Degree ◽  
Exafs Spectra

Most of the main features of water oxidation in photosystem II are now well understood, including the mechanism for O–O bond formation. For the intermediate S2 and S3 structures there is also nearly complete agreement between quantum chemical modeling and experiments. Given the present high degree of consensus for these structures, it is of high interest to go back to previous suggestions concerning what happens in the S2–S3 transition. Analyses of extended X-ray adsorption fine structure (EXAFS) experiments have indicated relatively large structural changes in this transition, with changes of distances sometimes larger than 0.3 Å and a change of topology. In contrast, our previous density functional theory (DFT)(B3LYP) calculations on a cluster model showed very small changes, less than 0.1 Å. It is here found that the DFT structures are also consistent with the EXAFS spectra for the S2 and S3 states within normal errors of DFT. The analysis suggests that there are severe problems in interpreting EXAFS spectra for these complicated systems.

Chapter 9. Energy from Photosystem II: Manganese Water Oxidation Catalysts

2011 ◽  
pp. 249-272
Author(s):  
Robin Brimblecombe ◽  
G. Charles Dismukes ◽  
Gerhard F. Swiegers ◽  
Leone Spiccia
Keyword(s):  
Photosystem Ii ◽  
Water Oxidation ◽  
Oxidation Catalysts

scholarly journals FTIR detection of water reactions in the oxygen-evolving centre of photosystem II

2007 ◽  
Vol 363 (1494) ◽  
pp. 1189-1195 ◽  
Author(s):  
Takumi Noguchi
Keyword(s):  
Photosystem Ii ◽  
Water Oxidation ◽  
State Transitions ◽  
Proton Release ◽  
Difference Spectra ◽  
Band Shift ◽  
Bonding Structure ◽  
Ph Dependency ◽  
Ftir Difference Spectroscopy ◽  
Oxygen Evolving

Flash-induced Fourier transform infrared (FTIR) difference spectroscopy has been used to study the water-oxidizing reactions in the oxygen-evolving centre of photosystem II. Reactions of water molecules were directly monitored by detecting the OH stretching bands of weakly H-bonded OH of water in the 3700–3500 cm −1 region in FTIR difference spectra during S-state cycling. In the S 1 →S 2 transition, a band shift from 3588 to 3617 cm −1 was observed, indicative of a weakened H-bond. Decoupling experiments using D 2 O : H 2 O (1 : 1) showed that this OH arose from a water molecule with an asymmetric H-bonding structure and this asymmetry became more significant upon S 2 formation. In the S 2 →S 3 , S 3 →S 0 and S 0 →S 1 transitions, negative bands were observed at 3634, 3621 and 3612 cm −1 , respectively, representing formation of a strong H-bond or a proton release reaction. In addition, using complex spectral features in the carboxylate stretching region (1600–1300 cm −1 ) as ‘fingerprints’ of individual S-state transitions, pH dependency of the transition efficiencies and the effect of dehydration were examined to obtain the information of proton release and water insertion steps in the S-state cycle. Low-pH inhibition of the S 2 →S 3 , S 3 →S 0 and S 0 →S 1 transitions was consistent with a view that protons are released in the three transitions other than S 1 →S 2 , while relatively high susceptibility to dehydration in the S 2 →S 3 and S 3 →S 0 transitions suggested the insertion of substrate water into the system during these transitions. Thus, a possible mechanism of water oxidation to explain the FTIR data is proposed.

scholarly journals Recent pulsed EPR studies of the Photosystem II oxygen-evolving complex: implications as to water oxidation mechanisms

2004 ◽  
Vol 1655 ◽  
pp. 158-171 ◽  
Author(s):  
R.David Britt ◽  
Kristy A Campbell ◽  
Jeffrey M Peloquin ◽  
M.Lane Gilchrist ◽  
Constantino P Aznar ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
Water Oxidation ◽  
Oxygen Evolving Complex ◽  
Pulsed Epr ◽  
Oxygen Evolving ◽  
Oxidation Mechanisms

Inside Back Cover: Scalable Synthesis of Efficient Water Oxidation Catalysts: Insights into the Activity of Flame-Made Manganese Oxide Nanocrystals (ChemSusChem 24/2015)

ChemSusChem ◽  
2015 ◽  
Vol 8 (24) ◽  
pp. 4275-4275
Author(s):  
Guanyu Liu ◽  
Jeremy Hall ◽  
Noushin Nasiri ◽  
Thomas Gengenbach ◽  
Leone Spiccia ◽  
...  
Keyword(s):  
Manganese Oxide ◽  
Water Oxidation ◽  
Oxidation Catalysts ◽  
Back Cover ◽  
Scalable Synthesis

scholarly journals Synthesis of an amorphous Geobacter-manganese oxide biohybrid as an efficient water oxidation catalyst

2020 ◽  
Vol 22 (17) ◽  
pp. 5610-5618
Author(s):  
Shafeer Kalathil ◽  
Krishna P. Katuri ◽  
Pascal E. Saikaly
Keyword(s):  
Manganese Oxide ◽  
Water Oxidation ◽  
Geobacter Sulfurreducens ◽  
Oxidation Catalyst ◽  
Oxidation Catalysts

Self-decorated Mn2O3 nanocrystals on Geobacter sulfurreducens were synthesized as sustainable and efficient water oxidation catalysts.

Sign in / Sign up

Export Citation Format

Share Document