Cysteine synthase A; Derived by automated computational analysis using gene prediction method: Protein Homology; Belongs to the cysteine synthase/cystathionine beta- synthase family.

5-methyltetrahydropteroyltriglutamate-- homocysteine methyltransferase; Catalyzes the formation of tetrahydropteroyl-L-glutamate and methionine from L-homocysteine and 5-methyltetrahydropteroyltri-L-glutamate; Derived by automated computational analysis using gene prediction method: Protein Homology.

O-acetylhomoserine aminocarboxypropyltransferase; Catalyzes the formation of L-methionine and acetate from O-acetyl-L-homoserine and methanethiol; Derived by automated computational analysis using gene prediction method: Protein Homology.

O-succinylhomoserine sulfhydrylase; Catalyzes the formation of L-homocysteine from O-succinyl-L- homoserine (OSHS) and hydrogen sulfide.

Sulfurtransferase; Derived by automated computational analysis using gene prediction method: Protein Homology.

S-(hydroxymethyl)glutathione synthase; Frameshifted; Derived by automated computational analysis using gene prediction method: Protein Homology.

Adenosylhomocysteinase; May play a key role in the regulation of the intracellular concentration of adenosylhomocysteine.

Homoserine dehydrogenase; Catalyzes the formation of L-aspartate 4-semialdehyde from L-homoserine; Derived by automated computational analysis using gene prediction method: Protein Homology.

Threonine ammonia-lyase, 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.