Genetically modified isopropylmalate isomerase enzyme complexes and processes to prepare elongated 2-ketoacids and C5-C10 compounds therewith

A genetically modified LeuCD′ enzyme complex comprising:

• (a) a genetically modified LeuC′ subunit comprising:
• (1) an amino acid sequence with at least 95% homology to SEQ ID NO:
• 1 having a C-terminus;
• and
• (2) a C-terminal amino acid or peptide coupled to the C-terminus of the amino acid sequence of (a)(1), wherein the C-terminal amino acid is chosen from any naturally occurring amino acid, and wherein the C-terminal peptide comprises an amino acid sequence:
• (Xaa)1(Xaa)2(Xaa)3(Xaa)4(Xaa)5(Xaa)6(Xaa)7(Xaa)8(Xaa)9(Xaa)10 (SEQ ID NO:
• 39) in which:
• (Xaa)1, (Xaa)2, (Xaa)3, (Xaa)4, (Xaa)5, (Xaa)6, (Xaa)7, (Xaa)8, (Xaa)9, and (Xaa)10 are each independently chosen from any naturally occurring amino acid, or are absent, provided that at least two of (Xaa)1, (Xaa)2, (Xaa)3, (Xaa)4, (Xaa)5, (Xaa)6, (Xaa)7, (Xaa)8, (Xaa)9, or (Xaa)10 are present in the C-terminal peptide;
• and
• (b) a LeuD subunit comprising an amino acid sequence with at least 90% homology to SEQ ID NO:
• 2, wherein the genetically modified LeuCD′ enzyme complex has activity against 2-hexylmalate (2-HM).