A2F2 · Beyond Biopolymers: Protein-Sized Aromatic Amide Functional Foldamers

Nature has evolved ultimate chemical functions based on controlling and altering conformation of its molecular machinery. Prominent examples include enzyme catalysis and information storage/duplication in nucleic acids. These achievements are based on large and complex yet remarkably defined structures obtained through folding of polymeric chains and a subtle interplay of non-covalent forces. Nature uses a limited set of building blocks – e.g. twenty amino-acids and four nucleobases – with specific abilities to impart well-defined folds. In the last decade, chemists have discovered foldamers: non-natural oligomers and polymers also prone to adopt folded structures. The emergence of foldamers has far reaching implications. A new major long term prospect is open to chemistry: the de novo synthesis of artificial objects resembling biopolymers in terms of their size, complexity, and efficiency at achieving defined functions, yet having chemical structures beyond the reach of biopolymers amenable to new properties and functions. The PI of this project has shown internationally recognized leadership in the development of a class of foldamers, aromatic oligoamides, whose features arguably make them the most suitable candidates to systematically explore what folded structures beyond biopolymers give access to. This project aims at developing methods to allow the routine fabrication of 20-40 units long aromatic oligoamide foldamers (6-15 kDa) designed to fold into artificial molecular containers having engineerable cavities and surfaces for molecular recognition of organic substrates, in particular large peptides and saccharides, polymers, and proteins. The methodology rests on modelling based design, multistep organic synthesis of heterocyclic monomers and their assembly into long sequences, structural elucidation using, among other techniques, x-ray crystallography, and the physico-chemical characterization of molecular recognition events.