Escherichia coli csrB gene, RNA encoded thereby, and methods of use thereof

Abstract

The invention includes the gene csrB, the RNA encoded thereby and methods of use thereof. csrB RNA binds to and antagonizes the ability of CsrA to down-regulate the production of certain metabolic products. This invention is also drawn to methods of using csrB polynucleotides, and combination of csrB polynucleotides and CsrA polypeptides and antibodies that bind to such combinations.

What is claimed is:  
     
         1 . An isolated csrB polynucleotide.  
     
     
         2 . The polynucleotide according to  claim 1  wherein the nucleotide sequence has at least 70% identity to that depicted in FIG. 1, and which comprises at least one binding site for CsrA or a complement of a binding site for CsrA.  
     
     
         3 . The polynucleotide according to  claim 1  wherein the nucleotide sequence is that depicted in FIG. 1.  
     
     
         4 . A composition comprising a csrB polynucleotide and CsrA.  
     
     
         5 . A composition according to  claim 4  wherein the ratio of csrB polynucleotide to CsrA is about 1:18.  
     
     
         6 . A method of altering the metabolism or structural or functional properties of a cell comprising altering genetic expression or CsrA-binding activity of csrB.  
     
     
         7 . The method according to  claim 6 , wherein CsrA-binding activity of csrB is altered by mutating csrB.  
     
     
         8 . The method according  claim 6 , wherein a result of altered genetic expression of csrB is a change in the level of production of a metabolic compound, wherein the level of production is at least partially regulated by CsrA.  
     
     
         9 . The method according  claim 6 , wherein a result of altered genetic expression of csrB is a change in glycogen biosynthesis or gluconeogenesis.  
     
     
         10 . The method according to  claim 6  wherein expression of the csrB gene is increased.  
     
     
         11 . The method according to  claim 6  wherein expression of the csrB gene is decreased.  
     
     
         12 . The method according to  claim 6  wherein expression of the csrB gene is under inducible control.  
     
     
         13 . An antibody capable of binding to a composition comprising CsrA and a csrB polynucleotide.  
     
     
         14 . A method of modulating the level of production of a metabolic compound, wherein the level of production is at least partially regulated by CsrA, comprising the step of binding an antibody of  claim 13  to CsrA.  
     
     
         15 . A vector comprising a csrB gene, further comprising a csrA gene.  
     
     
         16 . A vector according to  claim 15 , wherein the csrB gene and csrA gene are controlled by different inducible promoters.  
     
     
         17 . A method of modulating the level of production of a metabolic compound, wherein the level of production is at least partially controlled by CsrA, comprising the steps of: 
 (a) introducing a vector of  claim 16  into a host cell;    (b) raising the level of production of the metabolic compound by inducing expression of csrB.    
     
     
         18 . A method according to  claim 17  further comprising the step: 
 (c) decreasing the level of production of the metabolic compound by inducing expression of csrA.