Patellamides peptidic macrocycles

Prochloron spp. synthesize patellamides using a bacteriocin-like process. " The final patellamide structures are directly encoded on a precursor peptide, PatE. This linear, ribosomally encoded peptide must be modified and cleaved to yield heterocyclized, macrocyclized patellamides. In particular, the patellamides must be cut out of the precursor peptide from both their C- and N-termini, a property not yet observed in any other cyclic... 

One also has to consider that not aU amino add-based natural ligands are structurally so complex as a protein. There are a number of relatively low-molecular-weight natural peptides, for example, cyclopeptides, that very efQciendy and selectively interact with a complementary substrate. Notable examples are the antibiotics vaUnomycin, 1, and vancomycin, 2, as weU as the natural macrocyclic ligand patellamide A, 3 (Scheme 1). 

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