Coryneform bacteria with altered glucokinase activity in the production of L-lysine
The invention relates to alleles of the glk gene from coryneform bacteria coding for glucokinases, and to processes for the production of L-lysine by fermentation using bacteria containing such alleles.
1. An isolated protein comprising the amino acid sequence of SEQ ID NO:2, wherein:
a) the amino acid at position 213 is an L-amino acid other than L-alanine and
b) said protein has glucokinase activity.
2. The isolated protein of claim 1 , wherein said amino acid at position 213 is L-valine.
3. The isolated protein of claim 1 , wherein said amino acid sequence consists of the amino acid sequence of SEQ ID NO:2 but wherein the amino acid at position 213 is an b-amino acid other than L-alanine.
4. The isolated protein of claim 3 , wherein said amino acid at position 213 is L-valine.
5. An isolated nucleic acid comprising a nucleotide sequence encoding the protein of any one of claims 1 - 4 .
6. An isolated nucleic acid encoding the protein of claim 4 and having glucokinase activity, said isolated nucleic acid comprising the nucleotide sequence of SEQ ID NO:3.
7. A vector comprising the nucleotide sequence of the nucleic acid of claim 5 .
8. A coryneform bacteria transformed with the vector of claim 7 .
9. A process for the production of L-lysine or of a feed additive containing L-lysine, comprising:
a) fermenting the coryneform bacteria of claim 8 under conditions suitable for the production of L-lysine, and
b) isolating said L-lysine or the fermentation liquor containing said L-lysine.
10. The process of claim 9 wherein said coryneform bacteria are of the species Coryneform glutamicum.
11. A process for the production of a composition of L-lysine or of a feed additive containing L-lysine, comprising:
a) fermenting coryneform bacteria containing a nucleotide sequence encoding the enzyme glucokinase, wherein said glucokinase comprises the amino acid sequence of SEQ ID NO:2 and in the encoded amino acid sequence, L-alanine at position 213 has been replaced by a different proteinogenic amino acid,
b) concentrating the L-lysine in the fermentation liquor,
c) isolating said L-lysine or the fermentation liquor containing said L-lysine.
12. The process of claim 11 , wherein said amino acid at position 213 is L-valine.
13. The process of either claim 11 or claim 12 , wherein said composition of L-lysine or said fermentation liquor comprises >0 to 100% of the constituents of said fermentation liquor and/or of the biomass present during fermentation.
14. An isolated nucleic acid consisting of a nucleotide sequence encoding the protein of any one of claims 1 - 4 .
15. An isolated nucleic acid, encoding the protein of claim 4 , wherein said nucleic acid consists of the nucleotide sequence of SEQ ID NO:3.