Methods for cloning and manipulating genomes
Compositions and methods are disclosed herein for cloning a synthetic or a semi-synthetic donor genome in a heterologous host cell. In one embodiment, the donor genome can be further modified within a host cell. Modified or unmodified genomes can be further isolated from the host cell and transferred to a recipient cell. Methods disclosed herein can be used to alter donor genomes from intractable donor cells in more tractable host cells.
1. A method for creating a self-replicating synthetic cell, said method comprising:
(i) assembling a synthetic bacterial, cyanobacterial, or microalgal donor genome as one or more fragments and introducing the donor genome as one or more fragments and a host vector into a yeast host cell, wherein the donor genome and the host vector are joined prior to or after introduction into the yeast host cell;
(ii) recovering the assembled donor genome from the yeast host cell;
(iii) performing step a) or b) or c) wherein a), b) and c) comprise
a) preparing the donor genome for transplantation into a bacterial, cyanobacterial, or microalgal recipient cell by methylating the donor genome;
b) preparing a bacterial or cyanobacterial or microalgal recipient cell by removing or inactivating a restriction endonuclease function present in the recipient cell that cuts the donor genome;
c) providing a bacterial, cyanobacterial, or microalgal recipient cell lacking a restriction endonuclease function that cuts the donor genome; and
(iv) introducing the recovered donor genome into the recipient cell,
thereby generating a self-replicating synthetic cell comprising the donor genome and controlled only by the donor genome, wherein the donor genome is sufficient to sustain viability and continuous self-replication of the recipient cell; and
wherein the synthetic cell supports gene expression from the donor genome and has a phenotype of the donor genome,
wherein the donor genome is an essentially intact genome that is at least a minimal genome, and is greater than about 300 kb in length.
2. The method of claim 1 , wherein the donor genome and the host vector are introduced into the host cell simultaneously.
3. The method of claim 1 , wherein the donor genome and host vector are joined prior to introduction into the yeast host cell by transforming the yeast host vector into a donor cell containing the donor genome.
4. The method of claim 3 , wherein the host vector is a centromeric plasmid.
5. The method of claim 1 , wherein the donor genome is modified within the yeast host cell.
6. The method of claim 1 , further comprising degrading or removing the endogenous genome of the recipient cell.
7. The method of claim 1 , wherein the recovered donor genome is methylated prior to introduction into the recipient cell.
8. The method of claim 1 , wherein the recipient cell's restriction endonuclease function is absent, removed or inactivated.
9. The method of claim 1 , further comprising introducing a second donor genome into the host cell, wherein the second donor genome is different from the first donor genome, thereby producing a host cell containing two different donor genomes.
10. The method of claim 9 , wherein introducing the second donor genome comprises mating the host cell containing the first donor genome with a second host cell containing the second donor genome.
11. The method of claim 1 , wherein the synthetic cell exhibits a phenotype corresponding to the donor genome incorporating any modifications thereto.
12. The method of claim 1 wherein the synthetic donor genome is assembled in vitro prior to introducing the donor genome into the host cell.
13. The method of claim 5 wherein the modification of the donor genome is selected from the group consisting of a substitution, a deletion, an insertion, a rearrangement, and a recombination.
14. The method of claim 13 wherein the modification is selected from the group consisting of: an insertion, a deletion, and a substitution.
15. The method of claim 5 wherein the modification is a homologous recombination.
16. The method of claim 1 wherein the donor genome is a bacterial genome and the recipient cell is a bacterial cell.
17. The method of claim 1 wherein the donor genome is a cyanobacterial genome and the recipient cell is a cyanobacterial cell.
18. The method of claim 1 wherein the donor genome is a microalgal genome and the recipient cell is a microalgal cell.
19. The method of claim 1 wherein the yeast host cell is Saccharomyces cerevisiae or Saccharomyces pombe.
20. The method of claim 16 , wherein the donor genome is a Mycoplasma genome and the recipient cell is a Mycoplasma cell.
21. The method of claim 19 , wherein the recipient cell is a Mycoplasma capricolum.
22. The method of claim 20 , wherein the recipient cell is a Mycoplasma capricolum.