FIGURE 7.
Modeling of domain II of EtfAf in a conformation in that the distance between the isoalloxazine rings of α-FAD and β-FAD are about 14 Å sufficient for an effective electron transfer. Because of the soft interface between the base of domain II and the domains I + III, a rotation of domain II is not severely restricted. It can also not be excluded that, alternatively, selective electron transfer between α-FAD and β-FAD is provided by fixing them in a distance that the rate is determined by the polypeptide tuned one-electron redox potentials of the isoalloxazine rings.