Alleles of the zwf gene from coryneform bacteria

Abstract

The invention relates to mutants and alleles of the zwf gene of coryneform bacteria, which encode variants of the Zwf subunit of glucose 6-phosphate dehydrogenase (EC: 1.1.1.49), and to processes for preparing amino acids, in particular L-lysine and L-tryptophan, by using bacteria which harbor said alleles.

1 - 65 . (canceled)  
     
     
         66 . An isolated polypeptide comprising the amino acid sequence of SEQ ID NO:2 except that any proteinogenic amino acid other than glycine is present at position 321 and/or any proteinogenic amino acid other than serine is present at position 8, and wherein said polypeptide has glucose 6-phosphate dehydrogenase activity.  
     
     
         67 . The isolated polypeptide of  claim 66 , wherein said proteinogenic amino acid at position 321 is L-serine.  
     
     
         68 . The isolated polypeptide of  claim 66 , wherein said polypeptide has an amino acid sequence that is 514 amino acids long.  
     
     
         69 . The isolated polypeptide of  claim 66 , wherein the amino acid sequence from position 312 to 330 corresponds to positions 312 to 330 of SEQ ID NO:6, SEQ ID NO:8 or SEQ ID NO:10.  
     
     
         70 . The isolated polypeptide of  claim 66 , wherein said isolated polypeptide comprises an amino acid sequence selected from the group consisting of: SEQ ID NO:6, SEQ ID NO:8 and SEQ ID NO:10.  
     
     
         71 . An isolated polynucleotide encoding the polypeptide of  claim 66 .  
     
     
         72 . The isolated polynucleotide of  claim 71 , wherein, in said polypeptide, the amino acid at position 321 is L-serine.  
     
     
         73 . The isolated polynucleotide of  claim 71 , wherein the encoded polypeptide comprises an amino acid sequence having a length of 514 amino acids.  
     
     
         74 . The isolated polynucleotide of  claim 71 , wherein, from amino acid sequence position 312 to 330, the encoded polypeptide comprises an amino acid sequence corresponding to positions 312 to 330 of SEQ ID NO:6, SEQ ID NO:8 or SEQ ID NO:10.  
     
     
         75 . The isolated polynucleotide of  claim 71 , wherein said isolated polynucleotide hybridizes with a nucleotide sequence complementary to SEQ ID NO:5, SEQ ID NO:7 or SEQ ID NO:9 under stringent conditions.  
     
     
         76 . The isolated polynucleotide of  claim 71 , wherein the encoded protein comprises an amino acid sequence selected from the group consisting of: SEQ ID NO:6, SEQ ID NO:8 and SEQ ID NO:10.  
     
     
         77 . The isolated polynucleotide of  claim 71 , wherein said isolated polynucleotide comprises the nucleotide sequence of SEQ ID NO:5, SEQ ID NO:7 or SEQ ID NO:9.  
     
     
         78 . The isolated polynucleotide of  claim 71 , wherein said isolated polynucleotide comprises the nucleotide sequence of SEQ ID NO:11.  
     
     
         79 . A vector comprising a sequence corresponding to the isolated polynucleotide of  claim 71 .  
     
     
         80 . An isolated coryneform bacterium comprising a polynucleotide encoding a polypeptide having the amino acid sequence of SEQ ID NO:2 except that any proteinogenic amino acid except glycine is present at position 321 and/or any proteinogenic amino acid except serine is present at position 8, and wherein said polypeptide has glucose 6-phosphate dehydrogenase activity.  
     
     
         81 . The isolated coryneform bacterium of  claim 80 , wherein said coryneform bacterium is selected from the group consisting of  Corynebacterium  efficiens,  Corynebacterium glutamicum, Corynebacterium thermoaminogenes  and  Corynebacterium  aminogenes.  
     
     
         82 . A process for preparing an L-amino acid, comprising: 
 a) fermenting an isolated coryneform bacterium in a suitable medium, said bacterium harboring at least one copy of a gene encoding a polypeptide with the amino acid sequence of SEQ ID NO:2 except that any proteinogenic amino acid other than glycine is present at position 321 and/or any proteinogenic amino acid other than serine is present at position 8, and wherein said polypeptide has glucose 6-phosphate dehydrogenase activity;    b) concentrating the L-amino acid in the fermentation broth or in the cells of said bacterium.    
     
     
         83 . The process of  claim 82 , wherein said L-amino acid is purified from the fermentation broth or cells of step b).  
     
     
         84 . The process of  claim 82 , further comprising: 
 c) concentrating said L-amino acid in said fermentation broth in step b, collecting said fermentation broth and then removing an amount of from 0 to 100% of the biomass present; and    d) preparing from the composition produced in step c, an essentially dry and shaped product by a method selected from the group consisting of granulation, compacting, spray drying and extrusion.    
     
     
         85 . The process of  claim 84 , wherein the dry and shaped product obtained in step d is sprayed with an oil.