Published US application 20150111269 to Butamax

Title: KETOL-ACID REDUCTOISOMERASE USING NADH

First 7 claims:

1. A mutant ketol-acid reductoisomerase enzyme comprising the amino acid sequence as set forth in SEQ ID NO: 29.

2. A nucleic acid molecule encoding the mutant ketol-acid reductoisomerase enzyme of claim 1.

3. A nucleic acid molecule encoding a mutant ketol-acid reductoisomerase enzyme having the amino acid sequence as set forth in SEQ ID NO:19.

4. A mutant ketol-acid reductoisomerase enzyme as set for in SEQ ID NO:19

5. A recombinant cell comprising the mutant ketol-acid reductoisomerase enzyme of claim 1.

6. A mutant ketol-acid reductoisomerase enzyme as set forth in SEQ ID NO:17 comprising at least one mutation at a residue selected from the group consisting of 24, 33, 47, 50, 52, 53, 61, 80, 115, 156, 165, and 170.

7. A mutant ketol-acid reductoisomerase enzyme according to claim 6 wherein: a) the residue at position 47 has an amino acid substation selected from the group consisting of A, C, D, F, G, I, L, N, P, H, T, E and Y; b) the residue at position 50 has an amino acid substitution selected from the group consisting of A, C, D, E, F, G, M, N, V, W and I; c) the residue at position 52 has an amino acid substitution selected from the group consisting of A, C, D, G, H, N, Y, and S; d) the residue at position 53 has an amino acid substitution selected from the group consisting of A, H, I, W, Y, C, and R; e) the residue at position 156 has an amino acid substitution of V; f) the residue at position 165 has an amino acid substitution of M; g) the residue at position 61 has an amino acid substitution of F; h) the residue at position 170 has an amino acid substitution of A; i) the residue at position 24 has an amino acid substitution of F; j) the residue at position 33 has an amino acid substitution of L; k) the residue at position 80 has an amino acid substitution of I; and l) the residue at position 115 has an amino acid substitution of L.