ENGINEERED CO2 FIXING MICROORGANISMS PRODUCING CARBON-BASED PRODUCTS OF INTEREST
The present disclosure identifies pathways and mechanisms to confer production of carbon-based products of interest such as ethanol, ethylene, chemicals, polymers, n-alkanes, isoprenoids, pharmaceutical products or intermediates thereof in photoautotrophic organisms such that these organisms efficiently convert carbon dioxide and light into carbon-based products of interest, and in particular the use of such organisms for the commercial production of ethanol, ethylene, chemicals, polymers, n-alkanes, isoprenoids, pharmaceutical products or intermediates thereof.
1 . A method for producing ethanol, comprising:
culturing an engineered photosynthetic microbe, wherein the photosynthetic microbe comprises a heterologous pyruvate decarboxylase, a heterologous NADPH-dependent alcohol dehydrogenase, and a heterologous catalase.
2 . The method of claim 1 , wherein the heterologous catalase is Synechocystis sp. PCC 6803 katG.
3 . The method of claim 1 , wherein the heterologous pyruvate decarboxylase is Zymomonas mobilis pyruvate decarboxylase.
4 . The method of claim 1 , wherein the heterologous alcohol dehydrogenase is Zymomonas mobilis adhII.
5 . The method of claim 1 , wherein the heterologous alcohol dehydrogenase is Moorella sp. HUC22-1 adhA.
6 . The method of claim 1 , wherein the photosynthetic microbe comprises heterologous Synechocystis sp. PCC6803 katG, a heterologous Zymomonas mobilis pyruvate decarboxylase, and a heterologous Zymomonas mobilis adhII.
7 . The method of claim 1 , wherein the photosynthetic microbe comprises a heterologous Synechocystis sp. PCC6803 katG, a heterologous Zymomonas mobilis pyruvate decarboxylase, and a heterologous Moorella sp. HUC22-1 adhA.
8 . The method of claim 1 wherein said photosynthetic microbe is a cyanobacterium.
9 . The method of claim 8 , wherein said cyanobacterium is a Synechococcus species.
10 . The method of claim 1 , wherein the NADPH-dependent alcohol dehydrogenase is an enzyme that has EC 1.1.1.2.
11 . The method of claim 1 , wherein the NADPH-dependent alcohol dehydrogenase comprises an amino acid sequence that is at least 95% identical to the amino acid sequence shown in SEQ ID NO:2.
12 . A method for producing ethanol, comprising:
(i) culturing an engineered photosynthetic microbe in a culture medium, wherein the photosynthetic microbe comprises a heterologous pyruvate decarboxylase, a heterologous NADPH-dependent alcohol dehydrogenase, and a heterologous catalase; and
(ii) exposing the engineered photosynthetic microbe to light and inorganic carbon, wherein said exposure results in the conversion of the inorganic carbon by the photosynthetic microbe into ethanol.
13 . An engineered photosynthetic microbe, wherein the photosynthetic microbe comprises a heterologous pyruvate decarboxylase and a heterologous NADPH-dependent alcohol dehydrogenase.
14 . The engineered photosynthetic microbe of claim 13 , wherein the heterologous pyruvate decarboxylase is Zymomonas mobilis pyruvate decarboxylase.
15 . The engineered photosynthetic microbe of claim 13 , wherein the heterologous alcohol dehydrogenase is Zymomonas mobilis adhII.
16 . The engineered photosynthetic microbe of claim 13 , wherein the heterologous alcohol dehydrogenase is Moorella sp. HUC22-1 adhA.
17 . The engineered photosynthetic microbe of claim 13 wherein said photosynthetic microbe is a cyanobacterium.
18 . The engineered photosynthetic microbe of claim 13 , wherein the NADPH-dependent alcohol dehydrogenase is an enzyme that has EC 1.1.1.2.
19 . The engineered photosynthetic microbe of claim 13 , wherein the NADPH-dependent alcohol dehydrogenase comprises an amino acid sequence that is at least 95% identical to the amino acid sequence shown in SEQ ID NO:2.
20 . The engineered photosynthetic microbe of claim 13 , wherein the microbe, when cultured, produces less acetaldehyde than an otherwise identical microbe lacking the NADPH-dependent alcohol dehydrogenase and cultured under identical conditions.