Engineered microorganisms having resistance to ionic liquids
View Patent ↗The present invention provides for a method of genetically modifying microorganisms to enhance resistance to ionic liquids, host cells genetically modified in accordance with the methods, and methods of using the host cells in a reaction comprising biomass that has been pretreated with ionic liquids.
1. A method of increasing the yield from a reaction in which soluble sugars are a source of carbon, the method comprising incubating a microorganism with biomass pretreated with an ionic liquid, wherein the biomass pretreated with an ionic liquid provides a source of soluble sugars as a carbon source, wherein the microorganism comprises a heterologous gene encoding a Major Facilitator Superfamily 1 (MFS 1) polypeptide operably linked to a promoter, wherein said MFS 1 polypeptide has an amino acid sequence with at least 95% sequence identity to the amino acid sequence set forth in SEQ ID NO:2, and wherein said MFS 1 polypeptide facilitates resistance of the microorganism to said ionic liquid as compared to a microorganism without said heterologous gene.
2. The method of claim 1 , wherein said biomass is incubated with said microorganism in a fermentation reaction that produces an alcohol.
3. The method of claim 1 , wherein said MFS 1 polypeptide comprises the amino acid sequence of SEQ ID NO:2.
4. The method of claim 1 , wherein said heterologous gene is operably linked to a tet repressor sequence.
5. The method of claim 4 , wherein said microorganism is genetically modified to express a tet repressor protein that binds to the tet repressor sequence.
6. The method of claim 1 , wherein said microorganism is a bacteria.
7. The method of claim 6 , wherein said bacteria is Escherichia coli.
8. The method of claim 1 , wherein said microorganism is a yeast or a filamentous fungi.
9. The method of claim 1 , wherein said ionic liquid comprises an anion, wherein said anion is Cl— or acetate.
10. The method of claim 1 , wherein said heterologous gene encoding said MFS 1 polypeptide is integrated into the genome of said microorganism.
11. The method of claim 1 , wherein said microorganism is generated by transforming said microorganism with an expression cassette, wherein the said expression cassette comprises said heterologous gene encoding said MFS 1 polypeptide.