Serine hydroxymethyltransferase; Catalyzes the reversible interconversion of serine and glycine with tetrahydrofolate (THF) serving as the one-carbon carrier. This reaction serves as the major source of one-carbon groups required for the biosynthesis of purines, thymidylate, methionine, and other important biomolecules. Also exhibits THF-independent aldolase activity toward beta-hydroxyamino acids, producing glycine and aldehydes, via a retro-aldol mechanism. Thus, is able to catalyze the cleavage of allothreonine and 3-phenylserine. Also catalyzes the irreversible conversion of 5,10-m [...]

L-threonine 3-dehydrogenase, NAD(P)-binding; Catalyzes the NAD(+)-dependent oxidation of L-threonine to 2- amino-3-ketobutyrate. To a lesser extent, also catalyzes the oxidation of D-allo-threonine and L-threonine amide, but not that of D-threonine and L-allothreonine. Cannot utilize NADP(+) instead of NAD(+). Belongs to the zinc-containing alcohol dehydrogenase family.

L-threonine dehydratase, catabolic; 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. TdcB also dehydrates serine t [...]

L-threonine synthase; Catalyzes the gamma-elimination of phosphate from L- phosphohomoserine and the beta-addition of water to produce L- threonine. To a lesser extent, is able to slowly catalyze the deamination of L-threonine into alpha-ketobutyrate and that of L-serine and 3-chloroalanine into pyruvate. Is also able to rapidly convert vinylglycine to threonine, which proves that the pyridoxal p-quinonoid of vinylglycine is an intermediate in the TS reaction.

L-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.

Glycine decarboxylase, PLP-dependent, subunit P of glycine cleavage complex; The glycine cleavage system catalyzes the degradation of glycine. The P protein binds the alpha-amino group of glycine through its pyridoxal phosphate cofactor; CO(2) is released and the remaining methylamine moiety is then transferred to the lipoamide cofactor of the H protein; Belongs to the GcvP family.

NADP-dependent 3-hydroxy acid dehydrogenase; NADP-dependent dehydrogenase with broad substrate specificity acting on 3-hydroxy acids. Catalyzes the NADP-dependent oxidation of L- allo-threonine to L-2-amino-3-keto-butyrate, which is spontaneously decarboxylated into aminoacetone. Also acts on D-threonine, L-serine, D-serine, D-3-hydroxyisobutyrate, L-3-hydroxyisobutyrate, D-glycerate and L-glycerate. Able to catalyze the reduction of the malonic semialdehyde to 3-hydroxypropionic acid. YdfG is apparently supplementing RutE, the presumed malonic semialdehyde reductase involved in pyrimi [...]

Putative NAD-dependent oxidoreductase.

Catalase inhibitor protein; ATPase that binds to both the 70S ribosome and the 50S ribosomal subunit in a nucleotide-independent manner. Does not hydrolyze GTP; Belongs to the TRAFAC class OBG-HflX-like GTPase superfamily. OBG GTPase family. YchF/OLA1 subfamily.