Marcus cycle

Lam, P. J., Bishop, J. K. B., Henning, C. C., Marcus, M. A., Waychunas, G. A., and Fung, I. Y. (2006). Wintertime phytoplankton bloom in the subarctic Pacific supported by continental margin iron Global Biogeochem. Cycles 20, GB2006. 

Klevecz RR, Li CM, Marcus I et al (2008) Collective behavior in gene regulation the cell is an oscillator, the cell cycle a developmental process. FEBS J 275 2372-2384... 

Mason, R. P. Redox cycling of radical anion metabohtes of toxic chemicals and drugs and the Marcus theory of electron transfer. Environ. Health Perspect. 1990, 87, 237-243. 

Electrolysis of the solution beyond the Ru(bpy)3 potential produces base-labile lesions specifically at G. Thus, the chemical reaction that leads to cycling of the metal complex is oxidation of guanine to the radical cation. Using digital simulation, the rate constant for the chemical reaction can be measured from the data shown in Fig. 18. When the potential of the mediator is varied, a Marcus plot can be constructed. If Marcus theory is obeyed, the rate constant should vary linearly with the driving force with a slope of 1/2. Such a dependence is observed for oxidation of guanine by Rulbpyla and derivatives (Fig. 19). 

Pines, E., The Photoacidity of 1-Hydro-xypyrene from Forster Cycle to Marcus Theory, Summer School, Molecular Basis of Fast and Ultrafast Processes, Algarve (Portugal), June 12th-15th 2003. 

The electron-transfer aspect of the reaction was studied by using Marcus theory and various thermodynamic cycles. Thus, the thermochemistries of a number of electron-transfer schemes were considered. Through a series of logical arguments, the scheme settled upon was not electron transfer per se but rather electrophilic attack of PAH by nitrosated nitrogen tetroxide ... 

The Forster cycle is not capable of observing the details of the transfer reaction, since it is a thermodynamic determination of pAT (and hence AGr ). Thermodynamics provide no direct information about the kinetics. When used in conjunction with a model for proton transfer, such as the Marcus theory, thermodynamic quantities such as AGr do provide some insight into the reaction rate. The rates derived using the thermodynamic quantity AGr when compared with the measured rate provide a test of the Marcus theory. Free energy relationships like Bronsted plots provide information on how chemical reactivity varies with chemical structure and on th nature of the transition state. ... 

From the fact that the glyoxylate and TCA cycles have several enzymes (citrate synthetase, aconitase, malate dehydrogenase) in common it appeared axiomatic that they must operate together in the same intracellular compartment, the mitochondrion. Early experiments with crude particulate pellets containing mitochondria gave only partial support to this view since, although malate synthetase was present in such preparations, most of the isocitrate lyase was present in the supernatant fraction (Yamamoto and Beevers, 1961 Marcus and Velasco, 1960). 

Commonly applied models of reaction kinetics, such as the transition state theory or RRKM (Rice-Ramsperger-Kassel-Marcus) theory, cannot completely describe multistage catalytic cycles or even the simplest reactions in many cases. As a catalytic cycle is a nonlinear dynamic system, statements such as "the reaction is first order with respect to a component A" or "the reaction is zero order with respect to a component B" cannot be universally assumed. 

Muzina DJ, Momah C, Eudicone JM, Pikalov A, McQuade RD, Marcus RN, Sanchez R, Carlson BX. Aripiprazole monotherapy in patients with rapid-cycling... 

Me2-4,4 -bipy ) have been used to evaluate the rate constant for inter-molecular reaction transfer within the ion pair. Use of a thermochemical cycle has provided a value for the rate of the overall reaction [Fe(CN)6] + PQ " (k2 0.2 X 10" M s ), which compares well with Marcus theory predictions. It is suggested that data on electron transfer processes may be derived from analysis of charge transfer absorption band characteristics. 

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