Aerobic organisms, reactions involving

Cytochrome c and cytochrome/both are involved in the electron transfer chain from glucose metabolites to molecular oxygen in aerobic organisms. From values of the half-cell potentials of cytochrome c and of cytochrome/at 30°C, it is possible to calculate that is 0.11 V for the reaction in Equation (12.12) [4]. Hence... 

In broad terms the decomposition of organic matter under anaerobic conditions is expected to be slower than nnder aerobic conditions becanse the free energy changes for the reactions involved are mnch smaller (Table 4.1 and Fignre 4.3). For example, for the aerobic decomposition of CH2O ,... 

Radical substitution reactions involving allylic tin derivatives could be accompanied by a photoinduced 1,3-rearrangement54,55. A photostationary mixture of cinnamyl(tri-phenyl)stannane with its regioisomer l-phenylprop-2-enyl(triphenyl)stannane has been shown to form in the photolysis of ( )-cinnamyl(triphenyl)stannane in benzene under aerobic conditions, or in the presence of halogenated organic compounds or radicaltrapping reagents (equation 21). 

Reactions involving 02 radicals have also been tied to the deleterious effects of oxygen upon aerobic organisms (i, 3), probably as a result of similar Fenton-type chemical reactions. 

The superoxide anion is produced in living cells of aerobic organisms mostly as an unwanted by-product of oxidative metabolism (307). The intrinsic toxicity of superoxide has been the subject of a passionate debate in past years (308-310). It seems that O2 toxic effects are not due to direct interaction of the O2 species with biological substrates, but rather to the likely products of chemical reactions involving superoxide. 

At this point, one might ask why the reduction of pyruvate to lactate (a waste product in aerobic organisms) is the last step in anaerobic glycolysis, a pathway that provides energy for the organism by oxidation of nutrients. There is another point to consider about the reaction, one that involves the relative amounts of NAD+ and NADH in a cell. The half reaction of reduction can be written... 

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