Method of producing nylon
There is provided a method of producing aminohexanoic acid and/or aminohexanoic acid ester from synthesis gas, the method comprising: A. contacting the synthesis gas with at least one bacteria capable of carrying out the Wood-Ljungdahl pathway and the ethanol-carboxylate fermentation to produce hexanoic acid; and B. contacting the hexanoic acid with a genetically modified cell to produce aminohexanoic acid and/or aminohexanoic acid ester, wherein the genetically modified cell has an increased activity, in comparison with its wild type, of alkane monooxygenase, alcohol dehydrogenase, and ω-transaminase.
1. A method of producing 6-aminohexanoic acid and/or 6-aminohexanoic acid ester from synthesis gas, the method comprising:
A. contacting the synthesis gas with:
(i) at least one bacteria capable of carrying out both the Wood-Ljungdahl pathway and the ethanol-carboxylate fermentation to produce hexanoic acid; or
(ii) at least one bacteria capable of carrying out the Wood-Ljungdahl pathway and at least a second bacteria capable of carrying out ethanol-carboxylate fermentation to produce hexanoic acid; and
B. contacting the hexanoic acid with a genetically modified cell to produce 6-aminohexanoic acid and/or 6-aminohexanoic acid ester, wherein, in comparison with its wild type, the genetically modified cell has increased activity, of all three enzymes: alkane monooxygenase, alcohol dehydrogenase, and ω-transaminase, wherein the alcohol dehydrogenase is encoded by an AlkJ gene (EC 1.1.99-2).
2. The method of claim 1 , further comprising the step of esterification of the hexanoic acid of step A to produce a C1-C4 hexanoate and wherein the C1-C4 hexanoate is contacted with the genetically modified cell of step B.
3. The method of claim 2 , wherein the step of esterification involves contacting the hexanoic acid of step A with at least one C1-C4 alcohol to produce C1-C4 hexanoate.
4. The method of claim 2 , wherein the step of esterification is catalysed by at least one esterification bacteria.
5. The method of claim 1 , wherein in the genetically modified cell of step B,
a) the enzyme alkane monooxygenase is encoded by the AlkBGT gene from Pseudomonas putida;
b) the enzyme alcohol dehydrogenase is encoded by the AlkJ gene from Pseudomonas putida ; and/or
c) the enzyme ω-transaminase is the ω-transaminase CV2025 from Chromobacterium violaceum DSM30191.
6. The method of claim 1 , further comprising a step of converting the 6-aminohexanoic acid ester to 6-aminohexanoic acid.
7. The method of claim 6 , wherein the conversion of the 6-aminohexanoic acid ester to the 6-aminohexanoic acid is catalysed by lipase LipA from Pseudomonas fluorescens.
8. The method of claim 1 , wherein the cell of step B is selected from the group consisting of: a genetically modified Escherichia coli cell, a genetically modified Corynebacterium glutamicum cell and a genetically modified Pseudomonas putida cell.
9. The method of claim 1 , wherein the bacteria capable of carrying out the ethanol-carboxylate fermentation is selected from the group consisting of Clostridium kluyveri and C. Carboxidivorans.
10. The method of claim 3 , wherein the C1-C4 alcohol is methanol.
11. The method of claim 3 , wherein the hexanoic acid produced from the synthesis gas is first extracted before being contacted with the C1-C4 alcohol to produce C1-C4 hexanoate.
12. The method of claim 1 , wherein the cell is in a culture medium comprising amino acids, which function as amine donor for step B.
13. The method of claim 1 , wherein the 6-aminohexanoic acid is catalysed to form nylon.
14. The method of claim 13 , wherein the nylon is nylon-6,6.
15. The method of claim 1 , wherein the bacteria capable of carrying out the Wood-Ljungdahl pathway in step A is an acetogenic bacteria selected from the group consisting of: Acetoanaerobium notera, Acetonema longum, Acetobacterium carbinolicum, Acetobacterium malicum, Acetobacterium species no. 446 , Acetobacterium wieringae, Acetobacterium woodii, Alkalibaculum bacchi, Archaeoglobus fulgidus, Blautia producta, Butyribacterium methylotrophicum, Clostridium aceticum, Clostridium autoethanogenum, Clostridium carboxidivorans, Clostridium coskatii, Clostridium drakei, Clostridium formicoaceticum, Clostridium glycolicum, Clostridium ljungdahlii, Clostridium ljungdahlii C-01, Clostridium ljungdahlii ERI-2, Clostridium ljungdahlii 0-52, Clostridium mayombei, Clostridium methoxybenzovorans, Clostridium ragsdalei, Clostridium scatologenes, Clostridium species, Desulfotomaculum kuznetsovii, Desulfotomaculum thermobezoicum subsp. thermosyntrophicum, Eubacterium limosum, Methanosarcina acetivorans C2A, Moorella sp. HUC22-1, Moorella thermoacetica, Moorella thermoautotrophica, Oxobacter pfennigii, Sporomusa aerivorans, Sporomusa ovata, Sporomusa silvacetica, Sporomusa sphaeroides, Sporomusa termitida , and Thermoanaerobacter kivui.