3-Methyl-2-oxovaleric acid + L-Glutamic acid → L-Isoleucine + Oxoglutaric acid
(S)-2-Aceto-2-hydroxybutanoic acid + Hydrogen Ion + NADPH → (R) 2,3-Dihydroxy-3-methylvalerate + NADP
(R) 2,3-Dihydroxy-3-methylvalerate → 3-Methyl-2-oxovaleric acid + Water
2-Ketobutyric acid + Hydrogen Ion + Pyruvic acid → (S)-2-Aceto-2-hydroxybutanoic acid + Carbon dioxide
L-Threonine → (2Z)-2-aminobut-2-enoate + Hydrogen Ion + Water
acetohydroxybutanoate synthase / acetolactate synthase
2-iminobutanoate + Hydrogen Ion + Water → 2-Ketobutyric acid + Ammonium
(2Z)-2-aminobut-2-enoate → 2-iminobutanoate
acetohydroxybutanoate synthase / acetolactate synthase 2
acetolactate synthase / acetohydroxybutanoate synthase 3
3-Methyl-2-oxovaleric acid ↔ 2-Keto-3-methyl-valerate
Adenosine triphosphate + L-Isoleucine + Water → Adenosine diphosphate + Hydrogen Ion + L-Isoleucine + Phosphate
branched-chain amino-acid aminotransferase
L-Isoleucine (→), Sodium (→) Transport: Kluyvera ascorbata ATCC 33433, Periplasmic Space to Kluyvera ascorbata ATCC 33433, Cytosol