Transaminates branched-chain amino acids and ketoglutarate. Involved in the final step of the methionine regeneration pathway, where ketomethiobutyrate (KMTB) is converted to methionine via a transamination. The amino donor preference is isoleucine, leucine, valine, phenylalanine, and tyrosine. 2-oxoglutarate + L-leucine = 4-methyl-2-oxopentanoate + L-glutamate 2-oxoglutarate + L-isoleucine = (S)-3-methyl-2-oxopentanoate + L-glutamate 2-oxoglutarate + L-valine = 3-methyl-2-oxobutanoate + L-glutamate Inhibited by canaline. Amino-acid biosynthesis; L-isoleucine biosynthesis; L-isoleucine from 2-oxobutanoate: step 4/4. Amino-acid biosynthesis; L-leucine biosynthesis; L-leucine from 3-methyl-2-oxobutanoate: step 4/4. Amino-acid biosynthesis; L-valine biosynthesis; L-valine from pyruvate: step 4/4. Belongs to the class-IV pyridoxal-phosphate-dependent aminotransferase family.