*5.2.5 DUF*

PatA and PatG proteases contain a domain of unknown function sharing a sequence similarity of about 56%. DUF domains are found in PatA and PatG from the patellamide biosynthetic clusters. Epimerization follows heterocyclization and precedes oxidation. Epimerization is an important role of DUF domain, and its

phenomenon is chemically spontaneous. Crystal structure of PatG-DUF is a novel fold dimer with two zinc ions. Practical importance of the dimer remains unclear since, the residues involved in Zn2+ binding, which is necessary for dimerization are not conserved among DUF domains. DUF domain does not bind to the macrocycle or the core peptide alone.
