Methods and devices for high fidelity polynucleotide synthesis
Disclosed are methods for synthesizing and/or assembling at least one polynucleotide product having a predefined sequence from a plurality of different oligonucleotides. In exemplary embodiments, the methods involve synthesis and/or amplification of different oligonucleotides immobilized on a solid support, release of synthesized/amplified oligonucleotides in solution to form droplets, recognition and removal of error-containing oligonucleotides, moving or combining two droplets to allow hybridization and/or ligation between two different oligonucleotides, and further chain extension reaction following hybridization and/or ligation to hierarchically generate desired length of polynucleotide products.
1. A method for removing error-containing oligonucleotides synthesized on a solid support, the method comprising:
(a) synthesizing a first plurality of oligonucleotides in a chain extension reaction, wherein a second plurality of oligonucleotides immobilized on the solid support serves as a template in the chain extension reaction, and wherein the second plurality of oligonucleotides comprises one or more oligonucleotides comprising a sequence error;
(b) denaturing products of the chain extension reaction;
(c) contacting the first plurality of oligonucleotides with the second plurality of oligonucleotides under hybridization conditions to form duplexes; and
(d) separating error-containing oligonucleotides from oligonucleotides with error-free sequences.
2. The method of claim 1 , wherein the error-containing oligonucleotides are separated from oligonucleotides with error-free sequences using a component which actively selects for a sequence error.
3. The method of claim 2 , wherein the sequence error selecting component comprises a mismatch recognition protein MutS or a functional variant of MutS.
4. The method of claim 1 , wherein the chain extension reaction forms homo-duplexes.
5. The method of claim 1 , wherein the duplexes formed in step (c) comprise homo-duplexes and hetero-duplexes.
6. The method of claim 5 , wherein each hetero-duplex comprises at least one sequence error.
7. The method of claim 6 , wherein the sequence error is a sequence mismatch.
8. The method of claim 6 , wherein the step of separating comprises:
(a) denaturing the hetero-duplexes under stringent melt conditions without denaturing the homo-duplexes;
(b) removing the denatured error-containing oligonucleotides from the solid support; and
(c) denaturing the homo-duplexes, thereby forming a purified plurality of oligonucleotides with error-free sequences.
9. A method for removing error-containing oligonucleotides synthesized on a solid support, the method comprising:
(a) synthesizing a first plurality of oligonucleotides in a chain extension reaction on a first spot on said solid support, wherein a second plurality of oligonucleotides immobilized on said first spot on said solid support serve as templates in the chain extension reaction;
(b) denaturing products of the chain extension reaction;
(c) contacting the first plurality of oligonucleotides with a third plurality of oligonucleotides under hybridization conditions to form duplexes, wherein said third plurality of oligonucleotides are synthesized on a second spot on said solid support substantially in parallel to step a), and wherein said first and third plurality of oligonucleotides comprise sequences that are complementary; and
(d) separating error-containing oligonucleotides from oligonucleotides with error-free sequences.
10. The method of claim 9 , wherein the error-containing oligonucleotides are separated from oligonucleotides with error-free sequences using a component that actively selects for a sequence error.
11. The method of claim 10 , wherein the sequence error selecting component comprises a mismatch recognition protein MutS or a functional variant of MutS.
12. The method of claim 9 , wherein the chain extension reaction forms homo-duplexes.
13. The method of claim 9 , wherein the duplexes formed in step (c) comprise homo-duplexes and hetero-duplexes.
14. The method of claim 13 , wherein each hetero-duplex comprises at least one sequence error.
15. The method of claim 14 , wherein the sequence error is a sequence mismatch.
16. The method of claim 14 , wherein the step of separating comprises:
(a) denaturing the hetero-duplexes under stringent melt conditions without denaturing the homo-duplexes;
(b) removing the denatured error-containing oligonucleotides from the solid support; and
(c) denaturing the homo-duplexes, thereby forming a purified plurality of oligonucleotides with error-free sequences.