Materials and methods for the efficient production of acetate and other products

Abstract

The subject invention provides materials and methods wherein unique and advantageous combinations of gene mutations are used to direct carbon flow from sugars to a single product. The techniques of the subject invention can be used to obtain products from native pathways as well as from recombinant pathways. In preferred embodiments, the subject invention provides new materials and methods for the efficient production of acetate and pyruvic acid.

We claim:  
     
         1 . A method for enhancing the microbial production of a desired product wherein said method comprises culturing a microbe having one or more genetic modifications that reduce ATP, such that the microbe's sugar metabolism is increased as is the rate of production of the desired product.  
     
     
         2 . The method, according to  claim 1 , wherein said modification(s) decrease the amount of ATP produced during metabolism.  
     
     
         3 . The method, according to  claim 1 , wherein said modification(s) increase the rate of ATP consumption during metabolism.  
     
     
         4 . The method, according to  claim 1 , wherein said modification(s) decrease the amount of ATP produced during metabolism and increase the rate of ATP consumption during metabolism.  
     
     
         5 . The method, according to  claim 1 , wherein said genetic modification(s) result in the elimination or substantial reduction of ATP production by oxidative phosphorylation.  
     
     
         6 . The method, according to  claim 4 , wherein there is a retention of cytoplasmic F i -ATP synthase for consumption of ATP.  
     
     
         7 . The method, according to  claim 1 , wherein said microbe comprises genetic modifications that inactivate oxidative phosphorylation, disrupt the cyclic function of the tricarboxylic acid cycle, and eliminate one or more fermentation pathways.  
     
     
         8 . The method, according to  claim 1 , wherein the microbe is a derivative of  E. coli  that comprises one or more chromosomal deletions selected from the group consisting of focA-pflB; frdBC; ldhA; atpFH; sucA and adhE.  
     
     
         9 . The method, according to  claim 1 , which comprises introducing into said microbe, one or more mutations into chromosomal genes thereby inactivating one or more pathways selected from the group consisting of lactate dehydrogenase, pyruvate formatelyase, fumarate reductase, ATP synthase, alcohol/aldehyde dehydrogenase, and 2-ketoglutarate dehydrogenase.  
     
     
         10 . The method, according to  claim 1 , wherein the desired product is selected from the group consisting of acetic acid; 1,3-propanediol; 2,3-propanediol; pyruvate; dicarboxylic acids; adipic acid; amino acids; and alcohols.  
     
     
         11 . The method, according to  claim 10 , wherein said product is acetic acid.  
     
     
         12 . The method, according to  claim 10 , wherein said product is pyruvic acid.  
     
     
         13 . The method, according to  claim 10 , wherein said amino acid is selected from the group consisting of aliphatic and aromatic amino acids.  
     
     
         14 . The method, according to  claim 10 , wherein said alcohol is selected from the group consisting of ethanol, butanol, isopropanol and propanol.  
     
     
         15 . The method, according to  claim 1 , wherein said microbe is an  E. coli.    
     
     
         16 . The method, according to  claim 1 , wherein said microbe is selected from the group consisting of TC36, TC24, TC44, and SZ47.  
     
     
         17 . The method, according to  claim 16 , wherein said microbe is TC36.  
     
     
         18 . The method, according to  claim 16 , wherein said microbe is TC44.  
     
     
         19 . The method, according to  claim 1 , wherein the desired product is produced via a natural pathway.  
     
     
         20 . The method, according to  claim 1 , wherein the desired product is produced via a recombinant pathway.  
     
     
         21 . The method, according to  claim 1 , wherein said microbe is devoid of plasmids and antibiotic resistance genes.  
     
     
         22 . The method, according to  claim 1 , wherein said method comprises a two-step batch feeding strategy wherein a second addition of glucose follows the end of an initial growth phase.  
     
     
         23 . The method, according to  claim 22 , wherein said method further comprises a nitrogen limitation.  
     
     
         24 . A biocatalyst for acetate production wherein said biocatalyst is TC36.  
     
     
         25 . A biocatalyst for pyruvate production wherein said biocatalyst is TC44.