Process for cell-free production of chemicals
View Patent ↗An enzymatic process is described for the production of chemicals from carbon sources. In particular, according to one aspect, a process for the production of a target organic compound from a carbon source by a cell-free enzyme system is disclosed.
1. A process for the production of a target organic compound from a carbon source compound selected from glucose or a glucose-containing oligomer or polymer by a cell-free enzyme system, the process comprising
(i) converting glucose to pyruvate, wherein no net production of ATP occurs;
wherein the enzyme system comprises the following enzyme activities, for the conversion from glucose to pyruvate:
glucose dehydrogenase (EC 1.1.1.47),
gluconate dehydratase (EC 4.2.1.39) and
2-keto-3-deoxy gluconate aldolase (EC 4.1.2.14) and
(ii) converting pyruvate to the target organic compound.
2. The process of claim 1 , wherein the target organic compound is ethanol, n butanol, iso-butanol, or 2-butanol.
3. The process of claim 1 or 2 , wherein the production process is performed in a liquid system comprising two separate phases, and the target organic compound is mainly present in or forms one of the separate phases, and
wherein the process further comprises collecting the target organic compound from the separate phase.
4. The process of claim 3 , wherein an organic solvent is added to establish the two separate phases.
5. The process of claim 1 , wherein the carbon source compound is continuously fed to the process and the target organic compound is continuously removed.
6. The process of claim 1 , wherein the enzyme system comprises the following enzymes, for the conversion from glucose to pyruvate:
glucose dehydrogenase (EC 1.1.1.47),
gluconolactonase (EC 3.1.1.17),
gluconate dehydratase (EC 4.2.1.39),
2-keto-3-deoxy gluconate aldolase (EC 4.1.2.14),
aldehyde dehydrogenase (EC 1.2.1.3),
glycerate dehydrogenase (EC 1.1.1.29) or Hydroxypyruvate reductase (EC 1.1.1.81),
serine-pyruvate transaminase (EC 2.6.1.51),
L-serine ammonia-lyase (EC 4.3.1.17) and
alanine dehydrogenase (EC 1.4.1.1).
7. The process of claim 1 , wherein the enzyme system comprises the following enzyme activities for the conversion from glucose to pyruvate:
glucose dehydrogenase (EC 1.1.1.47),
gluconolactonase (EC 3.1.1.17),
gluconate dehydratase (EC 4.2.1.39),
2-keto-3-deoxy gluconate aldolase (EC 4.1.2.14),
aldehyde dehydrogenase (EC 1.2.1.3) and
glycerate dehydratase (EC 4.2.1).
8. The process of claim 1 , wherein ethanol is produced from glucose by an enzyme system comprising from 6 to 11 enzymes.
9. The process of claim 1 , wherein n-butanol is produced from glucose by an enzyme system comprising from 6 to 17 enzymes.
10. The process of claim 1 , wherein iso-butanol is produced by an enzyme system comprising from 6 to 14 enzymes.
11. The process of claim 1 , wherein 2-butanol is produced by an enzyme system comprising from 6 to 13 enzymes.
12. The process of claim 1 , wherein the conversion of glucose to pyruvate works completely without ATP and/or ADP as cofactors.
13. The process of claim 1 , wherein the enzyme system further comprises the following enzyme activities, for the conversion from glucose to pyruvate:
aldehyde dehydrogenase (EC 1.2.1.3)
phosphoglycerate kinase (EC 2.7.1),
enolase (EC 4.2.1.11),
pyruvate kinase (EC 2.7.1.40).
14. The process of claim 1 , wherein the enzyme system further comprises the following enzyme activities, for the conversion from glucose to pyruvate:
aldehyde dehydrogenase (EC 1.2.1.3),
glycerate dehydrogenase (EC 1.1.1.29)
serine-pyruvate transaminase (EC 2.6.1.51),
L-serine ammonia-lyase (EC 4.3.1.17) and
alanine dehydrogenase (EC 1.4.1.1).
15. The process of claim 1 , wherein the enzyme system further comprises the following enzyme activities, for the conversion from glucose to pyruvate:
aldehyde dehydrogenase (EC 1.2.1.3),
dihydroxyacid dehydratase (EC 4.2.1.9).