Genetically engineered bacterium with altered carbon monoxide dehydrogenase (CODH) activity

Patent metadata

Field	Value
Publication number	US-9365873-B2
Application number	US-201514753191-A
Country	US
Kind code	B2
Filing date	Jun 29, 2015
Priority date	Aug 11, 2014
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

The invention provides genetically engineered microorganisms with altered carbon monoxide dehydrogenase (CODH) activity and methods related thereto. In particular, the invention provides a genetically engineered carboxydotrophic acetogenic bacterium having decreased or eliminated activity of CODH1 and/or CODH2. In certain embodiments, the bacterium may also have increased activity of CODH/ACS. The invention further provides a method for producing a product by culturing the bacterium in the presence of a gaseous substrate comprising one or more of carbon monoxide, carbon dioxide, and hydrogen.

First claim

The invention claimed is:

1. A genetically engineered carboxydotrophic acetogenic bacterium having decreased or eliminated activity of CODH1 and/or CODH2 compared to a parental bacterium.

2. The bacterium of claim 1 , wherein the bacterium comprises at least one disruptive mutation in a CODH1 gene and/or CODH2 gene.

3. The bacterium of claim 2 , wherein the disruptive mutation decreases or eliminates expression of the CODH1 gene and/or the CODH2 gene compared to a parental bacterium.

4. The bacterium of claim 2 , wherein the disruptive mutation is a knockout mutation.

5. The bacterium of claim 1 , wherein the bacterium additionally has increased activity of CODH/ACS compared to the parental bacterium.

6. The bacterium of claim 5 , wherein the bacterium overexpresses a CODH/ACS gene compared to the parental bacterium.

7. The bacterium of claim 1 , wherein the bacterium produces one or more of ethanol and 2,3-butanediol.

8. The bacterium of claim 1 , wherein the bacterium produces a higher amount of ethanol, produces a lower amount of acetate, has a shorter lag phase, and/or has a higher growth rate compared to the parental bacterium.

9. The bacterium of claim 1 , wherein the bacterium consumes a gaseous substrate comprising one or more of CO, CO 2 , and H 2 .

10. The bacterium of claim 1 , wherein the parental bacterium is Clostridium autoethanogenum, Clostridium ljungdahlii , or Clostridium ragsdalei.

11. A method for producing a product, comprising culturing the bacterium of claim 1 in the presence of a gaseous substrate comprising one or more of CO, CO 2 , and H 2 , whereby the bacterium produces a product.

12. The method of claim 11 , wherein the bacterium comprises at least one disruptive mutation in a CODH1 gene and/or CODH2 gene.

13. The method of claim 12 , wherein the disruptive mutation decreased or eliminates expression of the CODH1 gene and/or the CODH2 gene compared to a parental bacterium.

14. The method of claim 12 , wherein the disruptive mutation is a knockout mutation.

15. The method of claim 11 , wherein the bacterium additionally has increased activity of CODH/ACS compared to the parental bacterium.

16. The method of claim 15 , wherein the bacterium overexpresses a CODH/ACS gene compared to the parental bacterium.

17. The method of claim 11 , wherein the product comprises one or more of ethanol and 2,3-butanediol.

18. The method of claim 11 , wherein the bacterium produces a higher amount of ethanol, produces a lower amount of acetate, has a shorter lag phase, and/or has a higher growth rate compared to the parental bacterium.

19. The method of claim 11 , wherein the parental bacterium is Clostridium autoethanogenum, Clostridium ljungdahlii , or Clostridium ragsdalei.

Assignees

• Koepke Michael
• Liew Fungmin
• Lanzatech New Zealand Ltd

Inventors

• Koepke Michael
• Liew Fungmin

Classifications

• C12P7/16

  Butanols · CPC title

• C12N15/74 Primary

  Vectors or expression systems specially adapted for prokaryotic hosts other than E. coli, e.g. Lactobacillus, Micromonospora · CPC title

• C12P7/065 Primary

  with microorganisms other than yeasts · CPC title

• C12P7/18 Primary

  polyhydric · CPC title

• Y02E50/10

  Biofuels, e.g. bio-diesel · CPC title