Method of transforming photosynthetic organisms
The invention provides methods of transforming photosynthetic organisms, such as green algae. The methods involve methylating one or more DNA fragments of a DNA construct and transforming the one or more fragments into the photosynthetic organism. The DNA fragments can be the product of a DNA amplification procedure, such as PCR or a PCR-like procedure. In one embodiment the one or more fragments of DNA that comprise a DNA construct are dam methylated prior to being transformed into the photosynthetic organism.
1. A method of transforming a photosynthetic Trebouxiophyte organism comprising:
contacting at least one DNA fragment with a dam methyltransferase to produce at least one methylated DNA fragment; and
transforming the photosynthetic Trebouxiophyte organism with the at least one methylated DNA fragment.
2. The method of claim 1 wherein the contacting is done in vitro.
3. The method of claim 2 wherein the DNA methylating enzyme performs m6A methylation.
4. The method of claim 2 wherein the dam methyltransferase is a prokaryotic dam methyltransferase.
5. The method of claim 2 wherein the at least one DNA fragment comprises a plurality of DNA fragments and together the plurality of DNA fragments comprise a DNA construct.
6. The method of claim 5 wherein the plurality of DNA fragments are assembled into the DNA construct prior to transforming the photosynthetic Trebouxiophyte organism.
7. The method of claim 5 wherein the at least one DNA fragment is a product of digestion with a restriction endonuclease.
8. The method of claim 2 wherein the organism is transformed using a biolistic method.
9. The method of claim 1 wherein the Trebouxiophyte alga is of the family Oocystacea.
10. The method of claim 5 wherein the DNA construct is a plasmid comprising a promoter, a gene of interest, and a terminator.
11. The method of claim 10 wherein the plasmid further comprises an origin of replication and/or a selectable marker.
12. The method of claim 9 wherein the alga is of the genus Oocystis.
13. The method of claim 2 wherein the at least one DNA fragment is provided as one or more linear fragment(s).
14. The method of claim 2 wherein the at least one DNA fragment is dam methylated.