Probable aminotransferase yfbQ; Involved in the biosynthesis of alanine.

Valine--pyruvate aminotransferase; Escherichia coli K-12 ortholog: b3572; Escherichia coli O157:H7 ortholog: z4997.

Probable aminotransferase yfbQ; Involved in the biosynthesis of alanine.

Dihydroxy-acid dehydratase; Escherichia coli K-12 ortholog: b3771; Escherichia coli O157:H7 ortholog: z5282.

Probable aminotransferase yfbQ; Involved in the biosynthesis of alanine.

Branched-chain amino acid aminotransferase; Acts on leucine, isoleucine and valine.

Probable aminotransferase yfbQ; Involved in the biosynthesis of alanine.

2-isopropylmalate synthase; Catalyzes the condensation of the acetyl group of acetyl-CoA with 3-methyl-2-oxobutanoate (2-oxoisovalerate) to form 3-carboxy-3- hydroxy-4-methylpentanoate (2-isopropylmalate); Belongs to the alpha-IPM synthase/homocitrate synthase family. LeuA type 1 subfamily.

Valine--pyruvate aminotransferase; Escherichia coli K-12 ortholog: b3572; Escherichia coli O157:H7 ortholog: z4997.

Probable aminotransferase yfbQ; Involved in the biosynthesis of alanine.

Valine--pyruvate aminotransferase; Escherichia coli K-12 ortholog: b3572; Escherichia coli O157:H7 ortholog: z4997.

Dihydroxy-acid dehydratase; Escherichia coli K-12 ortholog: b3771; Escherichia coli O157:H7 ortholog: z5282.

Valine--pyruvate aminotransferase; Escherichia coli K-12 ortholog: b3572; Escherichia coli O157:H7 ortholog: z4997.

Branched-chain amino acid aminotransferase; Acts on leucine, isoleucine and valine.

Valine--pyruvate aminotransferase; Escherichia coli K-12 ortholog: b3572; Escherichia coli O157:H7 ortholog: z4997.

2-isopropylmalate synthase; Catalyzes the condensation of the acetyl group of acetyl-CoA with 3-methyl-2-oxobutanoate (2-oxoisovalerate) to form 3-carboxy-3- hydroxy-4-methylpentanoate (2-isopropylmalate); Belongs to the alpha-IPM synthase/homocitrate synthase family. LeuA type 1 subfamily.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetolactate synthase isozyme I large subunit; Escherichia coli K-12 ortholog: b3671; Escherichia coli O157:H7 ortholog: z5165.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Ketol-acid reductoisomerase; Involved in the biosynthesis of branched-chain amino acids (BCAA). Catalyzes an alkyl-migration followed by a ketol-acid reduction of (S)-2-acetolactate (S2AL) to yield (R)-2,3-dihydroxy-isovalerate. In the isomerase reaction, S2AL is rearranged via a Mg-dependent methyl migration to produce 3-hydroxy-3-methyl-2-ketobutyrate (HMKB). In the reductase reaction, this 2-ketoacid undergoes a metal-dependent reduction by NADPH to yield (R)-2,3-dihydroxy-isovalerate.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Dihydroxy-acid dehydratase; Escherichia coli K-12 ortholog: b3771; Escherichia coli O157:H7 ortholog: z5282.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Branched-chain amino acid aminotransferase; Acts on leucine, isoleucine and valine.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetohydroxy acid synthase II; Escherichia coli O157:H7 ortholog: z5279.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetolactate synthase isozyme III small subunit; Escherichia coli K-12 ortholog: b0078; Escherichia coli O157:H7 ortholog: z0088.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetolactate synthase isozyme III large subunit; Escherichia coli K-12 ortholog: b0077; Escherichia coli O157:H7 ortholog: z0087.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetolactate synthase isozyme II small subunit; Escherichia coli K-12 ortholog: b3769; Escherichia coli O157:H7 ortholog: z5280.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

Acetolactate synthase isozyme I small subunit; Escherichia coli K-12 ortholog: b3670; Escherichia coli O157:H7 ortholog: z5164; Belongs to the acetolactate synthase small subunit family.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

2-isopropylmalate synthase; Catalyzes the condensation of the acetyl group of acetyl-CoA with 3-methyl-2-oxobutanoate (2-oxoisovalerate) to form 3-carboxy-3- hydroxy-4-methylpentanoate (2-isopropylmalate); Belongs to the alpha-IPM synthase/homocitrate synthase family. LeuA type 1 subfamily.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

3-isopropylmalate dehydrogenase; Catalyzes the oxidation of 3-carboxy-2-hydroxy-4- methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2- oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate. Belongs to the isocitrate and isopropylmalate dehydrogenases family. LeuB type 1 subfamily.

Threonine dehydratase biosynthetic; Catalyzes the anaerobic formation of alpha-ketobutyrate and ammonia from threonine in a two-step reaction. The first step involved a dehydration of threonine and a production of enamine intermediates (aminocrotonate), which tautomerizes to its imine form (iminobutyrate). Both intermediates are unstable and short-lived. The second step is the nonenzymatic hydrolysis of the enamine/imine intermediates to form 2- ketobutyrate and free ammonia. In the low water environment of the cell, the second step is accelerated by RidA.

3-isopropylmalate dehydratase large subunit; Catalyzes the isomerization between 2-isopropylmalate and 3- isopropylmalate, via the formation of 2-isopropylmaleate.