Assembly of large nucleic acids
A method to assemble any desired nucleic acid molecule by combining cassettes in vitro to form assemblies which are further combined in vivo, or by assembling large numbers of DNA fragments by recombination in a yeast culture to obtain desired DNA molecules of substantial size is described.
1. A method for the synthesis of a nucleic acid molecule of a predetermined nucleotide sequence, comprising:
a) providing a plurality of cassettes of 2-10 kb in length, each cassette containing a nucleotide sequence of a portion of the nucleic acid molecule, wherein the cassettes contain overlapping portions of the nucleotide sequence of the nucleic acid molecule and wherein the cassettes, if combined according to the overlapping portions, provide the complete nucleotide sequence of the nucleic acid molecule;
b) joining said cassettes in vitro to obtain a plurality of resulting subsets of from about 15 kb to about 200 kb or 50-500 kb in size; and wherein said subsets contain overlapping portions of the nucleic acid molecule of at least 80 bp and wherein the subsets, if assembled according to the overlapping portions, would provide the complete nucleotide sequence of the nucleic acid molecule; and
c) transfecting yeast host cells with a mixture of fragments of DNA comprising 10 or more subsets, and assembling the fragments of DNA comprising the 10 or more subsets in vivo in the yeast to obtain the nucleic acid molecule of predetermined nucleotide sequence, wherein one of the fragments of DNA includes an origin of replication operable in yeast.
2. The method of claim 1 , wherein a step b) and/ or step c) is repeated at least once.
3. The method of claim 1 , wherein said nucleic acid molecule of predetermined nucleotide sequence of step c) includes a centromere and/or a selectable marker.
4. The method of claim 1 , wherein one of the fragments of DNA is a vector and said vector comprises the origin of replication.
5. The method of claim 4 , wherein said vector comprises a centromere and/or a selectable marker.
6. The method of claim 1 , wherein one or more cassettes in step a) contains a watermark.
7. The method of claim 1 wherein the nucleic acid molecule of predetermined sequence is a synthetic genome.
8. The method of claim 1 wherein two of the fragments each comprise a telomere at one terminus.