Engineering microorganisms
The present disclosure provides, inter alia, Thraustochytrium and relevant methods and reagents, including engineered regulatory sequences from and/or operative in Thraustochytrid or Thraustochytrium , selectable markers useful for engineering microorganisms such as Thraustochytrids, means for mutagenizing microorganisms, novel strains produced by mutagenesis, and methods and compositions related to production of particular compounds in microorganisms.
1. A method for transforming a Thraustochytrium cell comprising the steps of:
(a) providing a competent Thraustochytrium cell;
(b) delivering a recombinant nucleic acid into the competent Thraustochytrium cell, wherein the recombinant nucleic acid comprises a selectable marker, a tubulin terminator that is at least 80% identical to SEQ ID NO:18 and a tubulin promoter that is at least 80% identical to SEQ ID NO:10; and
(c) culturing the competent Thraustochytrium cell in a culturing medium containing a selection agent that reduces growth of cells without the selectable marker.
2. The method of claim 1 , wherein selectable marker is an antibiotic resistance gene.
3. The method of claim 2 , wherein selection agent is an antibiotic.
4. The method of claim 3 , wherein antibiotic is zeocin.
5. The method of claim 4 , wherein the zeocin is present at a concentration greater than 50 μg/mL.
6. The method of claim 4 , wherein the zeocin is present at a concentration of about 100 μg/mL.
7. The method of claim 2 , wherein the antibiotic resistance gene is a zeocin resistance gene.
8. The method of claim 1 , wherein the recombinant nucleic acid further comprises a gene expression cassette distinct from the selectable marker.
9. The method of claim 1 , further comprising: (d) isolating a competent Thraustochytrium cell containing the selectable marker.
10. The method of claim 1 , wherein the step of delivering comprises biolistic delivery of particles coated with the recombinant nucleic acid.
11. The method of claim 10 , wherein the particles comprise gold particles.
12. The method of claim 1 , wherein the culturing medium contains between about 10 g/L and about 40 g/L of salt.
13. The method of claim 1 , wherein the recombinant nucleic acid comprises the tubulin promoter operably linked to the selectable marker.
14. The method of claim 1 , wherein the selectable marker comprises a ble gene.
15. The method of claim 14 , wherein the ble gene is a Sh ble gene, a Tn5 ble gene or a Sa ble gene.
16. The method of claim 1 , wherein the Thraustochytrium cell is ONC-T18.
17. The method of claim 1 , wherein the culturing medium contains between about 15 g/L and about 35 g/L salt.
18. The method of claim 1 , wherein the culturing medium contains between about 18 g/L and about 35 g/L salt.
19. A method for transforming a Thraustochytrium cell comprising the steps of:
(a) providing a competent Thraustochytrium cell;
(b) delivering a recombinant nucleic acid into the competent Thraustochytrium cell, wherein the recombinant nucleic acid comprises a selectable marker and a tubulin terminator that is at least 80% identical to SEQ ID NO:18; and
(c) culturing the competent Thraustochytrium cell in a culturing medium containing a selection agent that reduces growth of cells without the selectable marker.
20. The method of claim 19 , wherein selectable marker is an antibiotic resistance gene.
21. The method of claim 19 , wherein the selection agent is an antibiotic.
22. The method of claim 21 , wherein the antibiotic is zeocin.
23. The method of claim 21 , wherein the zeocin is contained in the culture medium at a concentration greater than 50 μg/mL.
24. The method of claim 21 , wherein the zeocin is contained in the culture medium at a concentration of about 100 μg/mL.
25. The method of claim 19 , wherein the recombinant nucleic acid further comprises a gene expression cassette distinct from the selectable marker.
26. The method of claim 19 , further comprising: (d) isolating a competent Thraustochytrium cell containing the selectable marker.
27. The method of claim 19 , wherein the step of delivering comprises biolistic delivery of particles coated with the recombinant nucleic acid.
28. The method of claim 27 , wherein the particles comprise gold particles.
29. The method of claim 19 , wherein the culturing medium contains between about 10 g/L and about 40 g/L of salt.
30. The method of claim 19 , wherein the culturing medium contains between about 15 g/L and about 35 g/L salt.
31. The method of claim 19 , wherein the culturing medium contains between about 18 g/L and about 35 g/L salt.
32. The method of claim 19 , wherein the selectable marker is a zeocin resistance gene.
33. The method of claim 19 , wherein the selectable marker comprises a ble gene.
34. The method of claim 33 , wherein the ble gene is a Sh ble gene, a Tn5 ble gene or a Sa ble gene.
35. The method of claim 19 , wherein the Thraustochytrium cell is ONC-T18.