Possible role of singlet oxygen in an ion-induced reaction mechanism of nucleus formation by sulphur dioxide

The reaction mechanism of the cationic rhodium(i)–BINAP complex catalysed isomerisation of allylic amines was explored using the artificial force induced reaction method with the global reaction route mapping strategy.

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Oxidations ofNω-Hydroxyarginine Analogues and VariousN-Hydroxyguanidines by NO Synthase II: Key Role of Tetrahydrobiopterin in the Reaction Mechanism and Substrate Selectivity

Chemical Research in Toxicology ◽

10.1021/tx0001068 ◽

2001 ◽

Vol 14 (2) ◽

pp. 202-210 ◽

Cited By ~ 16

Author(s):

Catherine Moali ◽

Jean-Luc Boucher ◽

Axelle Renodon-Corniere ◽

Dennis J. Stuehr ◽

Daniel Mansuy

Keyword(s):

Reaction Mechanism ◽

No Synthase ◽

Substrate Selectivity

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A meta-analysis and review examining a possible role for oxidative stress and singlet oxygen in diverse diseases

Biochemical Journal ◽

10.1042/bcj20161058 ◽

2017 ◽

Vol 474 (16) ◽

pp. 2713-2731 ◽

Cited By ~ 9

Author(s):

Athinoula L. Petrou ◽

Athina Terzidaki

Keyword(s):

Oxidative Stress ◽

Excited State ◽

Singlet Oxygen ◽

Ground State ◽

Meta Analysis ◽

Common Mechanism ◽

High Electron ◽

A Value ◽

First Excited State

From kinetic data (k, T) we calculated the thermodynamic parameters for various processes (nucleation, elongation, fibrillization, etc.) of proteinaceous diseases that are related to the β-amyloid protein (Alzheimer's), to tau protein (Alzheimer's, Pick's), to α-synuclein (Parkinson's), prion, amylin (type II diabetes), and to α-crystallin (cataract). Our calculations led to ΔG≠ values that vary in the range 92.8–127 kJ mol−1 at 310 K. A value of ∼10–30 kJ mol−1 is the activation energy for the diffusion of reactants, depending on the reaction and the medium. The energy needed for the excitation of O2 from the ground to the first excited state (1Δg, singlet oxygen) is equal to 92 kJ mol−1. So, the ΔG≠ is equal to the energy needed for the excitation of ground state oxygen to the singlet oxygen (1Δg first excited) state. The similarity of the ΔG≠ values is an indication that a common mechanism in the above disorders may be taking place. We attribute this common mechanism to the (same) role of the oxidative stress and specifically of singlet oxygen, (1Δg), to the above-mentioned processes: excitation of ground state oxygen to the singlet oxygen, 1Δg, state (92 kJ mol−1), and reaction of the empty π* orbital with high electron density regions of biomolecules (∼10–30 kJ mol−1 for their diffusion). The ΔG≠ for cases of heat-induced cell killing (cancer) lie also in the above range at 310 K. The present paper is a review and meta-analysis of literature data referring to neurodegenerative and other disorders.

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Singlet oxygen feedback delayed fluorescence of protoporphyrin IX in organic solutions

Photochemical & Photobiological Sciences ◽

10.1039/c6pp00298f ◽

2017 ◽

Vol 16 (4) ◽

pp. 507-518 ◽

Cited By ~ 13

Author(s):

Ivo S. Vinklárek ◽

Marek Scholz ◽

Roman Dědic ◽

Jan Hála

Keyword(s):

Partial Pressure ◽

Singlet Oxygen ◽

Protoporphyrin Ix ◽

Clinical Applications ◽

Delayed Fluorescence ◽

Diagnostic Tools ◽

Partial Pressure Of Oxygen ◽

High Concentrations ◽

Organic Solutions

The PpIX DF show the significant role of SOFDF mechanism at high concentrations and at atmospheric partial pressure of oxygen and should be considered when developing diagnostic tools for clinical applications.

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