Functional groups model protein reduction

Pumping Iron by Reduction of an Oxidized Functional Group Attached to the Model Protein... 

In an exactly analogous manner, equivalent behavior is seen with the series of Model Proteins il, in, and iv of Table 5.5 containing the nicotinamide functional group attached to a lysine (Lys, K) residue by an amide linkage (See Figure 5.20C).The systematic replacement of V by F shifts the reduction potential of the nicotinamide, that is, shifts the transition zone to lower electron concentrations, and results in a narrower transition zone. Figure 5.20C represents an explicit experimental example of the schematic representation in Figure 5.19C. 

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