Circular Permutation in Proteins
Figure 6
Transhydrogenases in various organisms can be found in three different domain arrangements.
In cattle, the three domains are arranged sequentially. In the bacteria E. coli, Rb. capsulatus, and R. rubrum, the transhydrogenase consists of two or three subunits. Finally, transhydrogenase from the protist E. tenella consists of a single subunit that is circularly permuted relative to cattle transhydrogenase [20].