Mutations for enhanced tyrosine production
The present invention provides cells genetically engineered to express mutated chorismate mutase/prephenate dehydrogenase (CM/PDH), the nucleic acid coding for each mutated CM/PDH and similar nucleic acids and methods for utilizing cells expressing mutated CM/PDH to produce tyrosine.
1. A cell engineered to express a chorismate mutase/prephenate dehydrogenase (CM/PDH) protein having at least 95% identity to SEQ ID NO: 1, wherein said protein
a) comprises a mutation in at least one amino acid at positions 95, 96, 180, 190, 324 or 357 of SEQ ID NO: 1; and
b) is subject to lower or no feedback inhibition by tyrosine.
2. The cell of claim 1 , wherein said mutation comprises a substitution of a phenylalanine with a leucine.
3. The cell of claim 1 , wherein said mutation is at position: 180, 190, 324, 357, or a combination thereof.
4. The cell of claim 1 , wherein said mutation comprises a substitution of: a glycine with an arginine at position 180, an aspartic acid with a glycine at position 190, a phenylalanine with a leucine at position 324, a phenylalanine with a leucine at position 357, or a combination thereof.
5. The cell of claim 1 , wherein said cell is a bacterium or a yeast.
6. The cell of claim 5 , wherein said bacterium belongs to the Acinetobacter, Aquifex, Bacillus, Bacteroides, Bordetella, Brevibacterium, Campylobacter, Corynebacterium, Erwinia, Escherichia, Haemophilus, Helicobacter, Idiomarina, Listeria, Pantoea, Photorhabdus, Pseudomonas, Salmonella, Shigella, Staphylococcus, Streptomyces, Synechococcus , or Yersinia genus.
7. The cell of claim 5 , wherein said yeast cell belongs to the Saccharomyces or Schizosaccharomyces genus.
8. An isolated nucleic acid comprising the nucleotide sequence as set forth in SEQ ID NO: 26, wherein said nucleic acid encodes a polypeptide involved in tyrosine biosyntheseis.
9. A vector comprising the nucleic acid of claim 8 .
10. A cell comprising the vector of claim 9 .
11. A cell engineered to express a chorismate mutase/prephenate dehydrogenase (CM/PDH) protein, wherein said protein
a) has the amino acid sequence as set forth in SEQ ID NO: 5; and
b) is subject to lower or no feedback inhibition by tyrosine.