NOVEL BACTERIA AND METHODS OF USE THEREOF
This invention relates generally to the field of microbial fermentation of gases. It more particularly relates to a novel strain of Clostridium autoethanogenum bacteria with improved efficiency in the production of ethanol by anaerobic fermentation of substrates containing carbon monoxide (CO).
1 - 29 . (canceled)
30 . A biologically pure isolate of a bacterium derived from Clostridium autoethanogenum wherein the selected bacterium ferments a substrate comprising CO to products comprising ethanol and wherein the bacterium has one or more improvements compared to a parent strain, the one or more improvements being selected from the group consisting of;
a. an increased production rate;
b. an increased growth rate;
c. an increased carbon monoxide uptake;
d. an increased tolerance to alcohol; and
e. a higher alcohol to acid production ratio.
31 . The bacterium of claim 1 wherein the parent strain is Clostridium autoethanogenum strain deposited at the German Collection of Microorganisms and cell cultures (DSMZ) under the accession number DSM19630.
32 . The selected bacterium of claim 1 wherein the bacterium is Clostridium autoethanogenum strain deposited at DSMZ under the accession number DSM23693.
33 . A biologically pure isolate of Clostridium autoethanogenum having at least one DNA sequence selected from Seq. ID. 1 to Seq. ID. 17.
34 . The bacterium of claim 30 wherein the production rate of the bacterium is at least 2 g ethanol/L fermentation broth/gram of biomass/day.
35 . The bacterium of claim 31 wherein the production rate of the bacterium is at least 2 g ethanol/L fermentation broth/gram of biomass/day.
36 . The bacterium of claim 32 wherein the production rate of the bacterium is at least 2 g ethanol/L fermentation broth/gram of biomass/day.
37 . The bacterium of claim 33 wherein the bacterium ferments a substrate comprising CO to products comprising ethanol and wherein the production rate of the bacterium is at least 2 g ethanol/L fermentation broth/gram of biomass/day
38 . The bacterium of claim 34 wherein the specific productivity is at least 7 g ethanol/L fermentation broth/gram of biomass/day.
39 . The bacterium of claim 30 wherein the products comprise ethanol and acetate.
40 . The bacterium of claims 30 wherein production rate of the bacterium is at least 10 g of ethanol/L of fermentation broth/day.
41 . The bacterium of claim 40 wherein the production rate of the bacterium is at least 50 g of ethanol/L of fermentation broth/day.
42 . The bacterium of claims 39 wherein the ethanol to acetate ratio is at least 2:1
43 . The bacterium of any one of claim 30 wherein the bacterium has a specific uptake of CO of at least 1.0 mmol CO/min/g biomass.
44 . The selected bacterium of claim 43 wherein the bacterium has a specific uptake of CO of at least 2.0 mmol CO/min/g biomass.
45 . The bacterium of claim 30 wherein the bacterium has a specific growth rate of at least 0.8 day −1 .
46 . The bacterium of claim 30 wherein the bacterium tolerates an alcohol concentration of up to 30 g/L of fermentation broth.
47 . The bacterium of claim 46 wherein the bacterium tolerates an alcohol concentration of up to 70 g/L of fermentation broth.