Methods and compositions for producing solvents
Described herein are methods, compositions and synthetic biology approaches for solvent production, including but not limited to butanol production. Described herein are recombinant bacteria and yeast strains which may be used in production of a solvent, including but not limited to butanol, from lignocellulosic and other plant-based feedstocks. Described herein are methods of producing solvents, including but not limited to butanol, using bacteria and yeast strains. Described herein are methods of producing organisms that display highly efficient butanol production.
1. A method of producing butanol comprising contacting a carbohydrate-comprising substrate with recombinant Clostridia or Escherichia coli bacteria transformed with a nucleic acid that results in a decreased level or activity of ManIIAB polypeptide or ManIIC polypeptide compared to the bacteria prior to transformation with a substrate, such that the substrate is metabolized to butanol.
2. The method claim 1 , wherein the bacterium prior to transformation is selected from the group consisting of Clostridium beijerinckii, Clostridium acetobutylicum, Clostridium saccharobutylicum , and Clostridium saccharoperbutylacetonicum.
3. The method of claim 2 , wherein the bacterium prior to transformation is Clostridium beijerinckii.
4. The method of claim 3 , wherein the bacterium prior to transformation is Clostridium beijerinckii NCIMB 8052 or a variant thereof.
5. The method of claim 4 , wherein the variant is Clostridium beijerinckii BA101.
6. The method of claim 4 , wherein the bacterium prior to transformation is Clostridium beijerinckii NCIMB 8052.
7. The method of claim 1 , wherein the ManIIAB polypeptide is encoded by SEQ ID NO:7.
8. The method of claim 1 , wherein the ManIIC polypeptide is encoded by SEQ ID NO:8.
9. The method of claim 1 , wherein the transforming nucleic acid encodes an antisense RNA.
10. The method of claim 1 , wherein the transforming nucleic acid knocks out or reduces the expression or activity of the ManIIAB polypeptide or ManIIC polypeptide of the bacterium when compared to the bacterium prior to its transformation.
11. The method of claim 1 , wherein the level of the ManIIAB polypeptide or ManIIC polypeptide is decreased as compared to the bacterium prior to transformation by manipulation of one or more of a promoter strength, a ribosomal binding site strength, and a regulatory region.
12. The method of claim 1 , wherein the recombinant bacterium further comprises an increased level of one or more of an alcohol dehydrogenase and butyryl-CoA dehydrogenase compared to the bacterium prior to transformation.
13. The method of claim 12 , wherein the recombinant bacterium is transformed with one or more additional nucleic acids that results in the increased expression of an alcohol dehydrogenase, a butyryl-CoA dehydrogenase, or both an alcohol dehydrogenase and a butyryl-CoA dehydrogenase compared to the bacterium prior to transformation.
14. The method of claim 13 , wherein the one more additional nucleic acids comprises a nucleic acid sequence with 80% or more identity to SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:12, or SEQ ID NO:14.
15. The method of claim 14 , wherein the one or more additional nucleic acids comprises SEQ ID NO:1 or SEQ ID NO:14.
16. The method of claim 14 , wherein the one or more additional nucleic acids comprises SEQ ID NO:2 or SEQ ID NO:12.