Redox Reactions in Metabolism

FIGURE 5.2 The stmcture of NAD and NADP and the role of the nicotinamide moiety as an electron acceptor. 

FIGURE 5.3 The flavin coenzymes FAD and FMN. Whereas FMN consists simply of riboflavin monophosphate, FAD has an AMP unit joined to riboflavin monophosphate. Note that in contrast to NAD+, flavins can be half-reduced to the stable radical FADH or fully reduced to the dihydroflavin shown. 

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