Isopropylmalate synthase variant and a method of producing L-leucine using the same
A novel modified polypeptide having an isopropylmalate synthase activity, a polynucleotide encoding the same, a microorganism comprising the polypeptide, and a method of producing L-leucine by culturing the microorganism.
1. A modified polypeptide having an isopropylmalate synthase activity, wherein arginine at position 558 from a N-terminus of a polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with histidine, alanine or glutamine; and/or glycine at position 561 from a N-terminus of a polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with arginine or tyrosine.
2. The modified polypeptide according to claim 1 , wherein the modified polypeptide consists of an amino acid sequence selected from the group consisting of SEQ ID NOS: 21, 22, 23, 25, 26, 28, 29, 31, 32, 34 and 35.
3. A modified polypeptide having an isopropylmalate synthase activity, wherein arginine at position 558 from an N-terminus of a polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with histidine, alanine, or glutamine, and glycine at position 561 from an N-terminus of a polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with aspartic acid, arginine, or tyrosine.
4. The modified polypeptide according to claim 3 , wherein the modified polypeptide consists of an amino acid sequence selected from the group consisting of SEQ ID NOS: 27, 30, and 33.
5. A polynucleotide encoding the modified polypeptide of claim 1 .
6. The polynucleotide according to claim 5 , wherein the polynucleotide consists of a nucleotide sequence selected from the group consisting of SEQ ID NOS: 36, 37, 38, 40, 41, 43, 44, 46, 47, 49 and 50.
7. A polynucleotide encoding the modified polypeptide of claim 2 .
8. A polynucleotide encoding the modified polypeptide of claim 3 .
9. The polynucleotide according to claim 8 , wherein the polynucleotide consists of a nucleotide sequence selected from the group consisting of SEQ ID NOS: 42, 45, and 48.
10. A microorganism of the genus Corynebacterium producing L-leucine, which is transformed with a vector comprising a polynucleotide encoding a modified polypeptide having an isopropylmalate synthase activity, wherein arginine at position 558 from a N-terminus of the polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with an amino acid residue other than arginine; and/or glycine at position 561 from a N-terminus of the polypeptide consisting of the amino acid sequence of SEQ ID NO: 1 is substituted with an amino acid residue other than glycine.
11. A microorganism of the genus Corynebacterium producing L-leucine, comprising the modified polypeptide of claim 1 .
12. The microorganism according to claim 11 , wherein the microorganism of the genus Corynebacterium is Corynebacterium glutamicum.
13. A microorganism of the genus Corynebacterium producing L-leucine, comprising the modified polypeptide of claim 2 .
14. A microorganism of the genus Corynebacterium producing L-leucine, comprising the modified polypeptide of claim 3 .
15. A microorganism of the genus Corynebacterium producing L-leucine, comprising the modified polypeptide of claim 4 .
16. A method of producing L-leucine, comprising:
(a) culturing the microorganism of the genus Corynebacterium producing L-leucine according to claim 11 in a medium to produce L-leucine; and
(b) recovering L-leucine from the cultured microorganism or the cultured medium.
17. A method of producing L-leucine, comprising:
(a) culturing the microorganism of the genus Corynebacterium producing L-leucine according to claim 13 in a medium to produce L-leucine; and
(b) recovering L-leucine from the cultured microorganism or the cultured medium.
18. A method of producing L-leucine, comprising:
(a) culturing the microorganism of the genus Corynebacterium producing L-leucine according to claim 14 in a medium to produce L-leucine; and
(b) recovering L-leucine from the cultured microorganism or the cultured medium.
19. A method of producing L-leucine, comprising:
(a) culturing the microorganism of the genus Corynebacterium producing L-leucine according to claim 15 in a medium to produce L-leucine; and
(b) recovering L-leucine from the cultured microorganism or the cultured medium.