Reverse beta oxidation pathway
The invention relates to recombinant microorganisms that have been engineered to produce various chemicals using genes that have been repurposed to create a reverse beta oxidation pathway. Generally speaking, the beta oxidation cycle is expressed and driven in reverse by modifying various regulation points for as many cycles as needed, and then the CoA thioester intermediates are converted to useful products by the action of termination enzymes.
1. An engineered microorganism, wherein the microorganism is engineered to overexpress β-oxidation cycle enzymes and one or more termination enzymes as compared to a corresponding wild-type microorganism, wherein said β-oxidation cycle enzymes comprise:
a) a thiolase catalyzing the conversion of (C n )-acyl CoA to β-ketoacyl-CoA,
b) a hydroxyacyl-CoA dehydrogenase catalyzing the conversion of β-ketoacyl-CoA to β-hydroxyacyl-CoA,
c) an enoyl-CoA hydratase catalyzing the conversion of β-hydroxyacyl-CoA to trans-Δ2-Enoyl-CoA, and
d) an acyl-CoA dehydrogenase or transenoyl-CoA reductase catalyzing the conversion of trans-Δ2-enoyl-CoA to (C n+2 )-acyl CoA,
wherein said β-oxidation cycle runs in the reverse/biosynthetic direction, as recited in enzyme reactions a) through d),
and
wherein said one or more termination enzymes are selected from the group consisting of an alcohol-forming coenzyme-A thioester reductase; an aldehyde-forming CoA thioester reductase and an alcohol dehydrogenase; a thioesterase; an acyl-CoA:acetyl-CoA transferase; a phosphotransacylase and a carboxylate kinase; an aldehyde-forming CoA thioester reductase and an aldehyde decarbonylase; and OleA, OleB, OleC, and OleD.
2. An engineered microorganism comprising a genotype, wherein said genotype comprises fadR, atoC(c), ΔarcA, Δcrp, crp*.
3. The engineered microorganism of claim 2 , wherein said genotype is selected from the group consisting of:
a) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, [tesB+];
b) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, [tesB+, yqeF+]; and
c) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, ΔfadB, [tesB+, yqeF+].
4. The engineered microorganism of claim 2 , wherein said genotype is selected from the group consisting of:
a) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, [tesA+];
b) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, [tesA+, yqeF+]; and
c) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔldhA, ΔmgsA, ΔydiO, [tesB+, yqeF+].
5. The engineered microorganism of claim 2 , wherein said genotype is selected from the group consisting of:
a) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, ΔydiO, [yqeF+, tesB+];
b) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [fadBA+, fadM+]; and
c) fadR, atoC(c), ΔarcA, Δcrp, crp, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [fadBA+, yciA+].
6. The engineered microorganism of claim 2 , wherein said genotype is selected from the group consisting of:
a) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [yqeF+, acrM+, PCC7942_orf1593+];
b) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [yqeF+, acrl+, PCC7942_orf1593+];
c) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [yqeF+, oleABCD+];
d) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [fadBA+, acrM+, PCC7942_orf1593+];
e) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [fadBA+, acrl+, PCC7942_orf1593+]; and
f) fadR, atoC(c), ΔarcA, Δcrp, crp*, ΔadhE, ΔfrdA, Δpta, ΔyqhA, ΔfucO, ΔfadD, [fadBA+, oleABCD+].
7. A method of making a product, said method comprising growing the engineered microorganism of claim 1 under microaerobic (<10% O 2 ) or anaerobic conditions in a glucose minimal medium supplemented with 0-100 μM FeSO 4 and 0-5 mM calcium pantothenate at a temperature of 30-40° C. for a time sufficient to allow production of a product and isolating said product, wherein said product is selected from the group consisting of trans Δ2 fatty alcohols, β-keto alcohols, 1-3 diols, β-hydroxy acids, carboxylic acids, and hydrocarbons.