Methods for cyclizing synthetic polymers
The invention provides methods and compositions for production of a cyclic polymer in a cell free system. In general, the methods of the invention involve ligating first and second recombinant intein domains to a linear synthetic polymer to form a compound containing the structure: D 1 -X (n) -D 2 , where D 1 is a first catalytic domain of an intein; D 2 is a second catalytic domain of an intein; where the second catalytic domain has at its N-terminus a first reactive site for the intein; and X (n) is a polymer of a number n of monomer X, where the polymer N-terminus has a second reactive site for the intein. D 1 -X (n) -D 2 compounds autocatalytically cyclize the X (n) polymer to produce a cyclic polymer. The invention finds use in a variety of drug discovery, clinical and therapeutic applications.
1. A method for making a cyclic polymer, comprising:
incubating a compound of the structure:
D 1 -X (n) -D 2
wherein D 1 is a first catalytic domain of an intein;
wherein X (n) is a polymer comprising n residues of a monomer X, n is at least 2, the polymer is not genetically encodable and is not made by a cell, and the polymer has a first reactive site for said intein at its N-terminus; and
wherein D 2 is a second catalytic domain of an intein, having at its N-terminus a second reactive site for said intein;
under intein reaction conditions to produce said cyclic polymer.
2. The method of claim 1 , wherein said incubating includes changing the temperature of said compound.
3. The method of claim 1 , wherein said synthetic polymer comprises at least one non-naturally occurring monomer.
4. The method of claim 1 , wherein said synthetic polymer comprises at least one amino acid monomer.
5. The method of claim 1 , wherein said synthetic polymer comprises at least one nucleotide monomer.
6. The compound of claim 1 , wherein D 1 , X (n) , and D 2 are joined by peptide bonds.
7. The compound of claim 1 , wherein n is at least 4.
8. The compound of claim 1 , wherein said monomers are amino acid monomers.
9. The compound of claim 1 , wherein said monomers are nucleotide monomers.