It is clear from the structures of bacterial members of MaoC dehydratase, Pfam:PF01575, that the full-length functional dehydratase enzyme is made up of two structures that dimerise to form a whole. Divergence of the N- and C- monomers in higher eukaryotes has led to two distinct domains, this one and MaoC_dehydratas. However, in order to function as an enzyme both are required together.