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- Antioxidants (1)
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- Bioenergetics in alkalophilic bacteria (1)
- Chemiosmotic theory (1)
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- Corrected pmf equation (1)
- Density functional theory (1)
- Excess hydroxyl anions (1)
- Excess protons (1)
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- Importance of water to life (1)
- Localized excess protons (1)
- Localized proton coupling (1)
- Nutrient cycling (1)
- Organoselenium compounds (1)
- Proton capacitor at water membrane interface (1)
- Proton electrostatic localization (1)
- Proton motive force (1)
- Proton/cation capacitor (1)
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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Long-Term Litter Decomposition Controlled By Manganese Redox Cycling, Marco Keiluweit, Peter Nico, Mark E. Harmon, Jingdong Mao, Jennifer Pett-Ridge, Markus Kleber
Long-Term Litter Decomposition Controlled By Manganese Redox Cycling, Marco Keiluweit, Peter Nico, Mark E. Harmon, Jingdong Mao, Jennifer Pett-Ridge, Markus Kleber
Chemistry & Biochemistry Faculty Publications
Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter …
Experimental Demonstration Of Localized Excess Protons At A Water-Membrane Interface, Haitham A. Saeed, James W. Lee
Experimental Demonstration Of Localized Excess Protons At A Water-Membrane Interface, Haitham A. Saeed, James W. Lee
Chemistry & Biochemistry Faculty Publications
The widespread Mitchellian proton motive force equation has recently been revised with the proton-electrostatics localization hypothesis, which, for the first time, successfully elucidates the 30-year longstanding energetic conundrum of ATP synthesis in alkalophilic bacteria. To demonstrate the fundamental behavior of localized protons in a pure water-membrane-water system in relation to the newly derived pmf equation, excess protons and excess hydroxyl anions were generated by utilizing an "open-circuit" water-electrolysis system and their distributions were tested using a proton-sensing aluminum membrane. The proton-sensing film placed at the membrane-water interface displayed dramatic localized proton activity while that placed into the bulk water phase …
Proton-Electrostatic Localization: Explaining The Bioenergetic Conundrum In Alkalophilic Bacteria, James Weifu Lee
Proton-Electrostatic Localization: Explaining The Bioenergetic Conundrum In Alkalophilic Bacteria, James Weifu Lee
Chemistry & Biochemistry Faculty Publications
The decades-longstanding energetic conundrum of alkalophilic bacteria as to how they are able to synthesize ATP has now, for the first time, been clearly solved using the proton-electrostatics localization hypothesis. This is a major breakthrough advance in understanding proton-coupling bioenergetics over the Nobel-prize work of Peter Mitchell’s chemiosmotic theory. The widespread textbook Mitchellian proton motive force (pmf) equation has now been significantly revised. Use of the newly derived equation results in an overall pmf value (215~233 mV) that is more than 4 times larger than that (44.3 mV) calculated from the Mitchellian equation for the alkalophilic bacteria growing at pH …
Effect Of Methoxy Substituents On The Activation Barriers Of The Glutathione Peroxidase-Like Mechanism Of An Aromatic Cyclic Seleninate, Craig A. Bayse, Ashley L. Shoaf
Effect Of Methoxy Substituents On The Activation Barriers Of The Glutathione Peroxidase-Like Mechanism Of An Aromatic Cyclic Seleninate, Craig A. Bayse, Ashley L. Shoaf
Chemistry & Biochemistry Faculty Publications
Density functional theory (DFT) models including explicit water molecules have been used to model the redox scavenging mechanism of aromatic cyclic seleninates. Experimental studies have shown that methoxy substitutions affect the rate of scavenging of reactive oxygen species differently depending upon the position. Activities are enhanced in the para position, unaffected in the meta, and decreased in the ortho. DFT calculations show that the activation barrier for the oxidation of the selenenyl sulfide, a proposed key intermediate, is higher for the ortho methoxy derivative than for other positions, consistent with the low experimental conversion rate.