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 2 subfamily.

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.

Homoserine dehydrogenase catalyzes NAD-dependent reduction of aspartate beta-semialdehyde into homoserine. This reaction is the third step in a pathway leading from aspartate to homoserine. Similar to TREMBL:Q9RAM9 (77%) and to pir|DEPSHA(PIR (Georgetown University) (56%). Pfam: Homoserine dehydrogenase; High confidence in function and specificity.

Probable threonine dehydratase; 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-methyl-2-oxobutanoate hydroxymethyltransferase; Catalyzes the reversible reaction in which hydroxymethyl group from 5,10-methylenetetrahydrofolate is transferred onto alpha- ketoisovalerate to form ketopantoate; Belongs to the PanB family.

Aspartate aminotransferase is important for the metabolism of amino acids and Krebs-cycle related organic acids. In plants, it is involved in nitrogen metabolism and in aspects of carbon and energy metabolism. The enzyme catalyses the reaction: L-aspartate + 2-oxoglutarate = oxaloacetate + L-glutamate Similar to trembl|Q8XZR9 (72%),to trembl|Q9RAN0 (62%) and to sprot|YFBQ_ECOLI (57%). Pfam (PF00155): Aminotransferases class-I; Specificity unclear.

Probable homoserine kinase; ThrH encodes a protein with an in vivo homoserine-kinase-like activity in P. aeruginosa. Homoserine kinase,the product of the thrB gene, catalyzes an obligatory step of threonine biosynthesis. Similar trembl|Q9I2Y2 (62%). Pfam (PF00702): haloacid dehalogenase-like hydrolase; Function unclear.

Probable homoserine kinase. Homology to thrB of M. flagellum of 51% (sprot|KHSE_METFL). CATALYTIC ACTIVITY: ATP + L-homoserine = ADP + O-phospho-L-homoserine. Pfam: Aminoglycoside phosphotransferase no signal peptide no TMHs; High confidence in function and specificity; Belongs to the pseudomonas-type ThrB family.

Bifunctional chorismate mutase/prephenate dehydratase P-protein, pheA,; High confidence in function and specificity.