Phosphoribosylaminoimidazolecarboxamide formyltransferase (AICAR transformylase); 10-formyltetrahydrofolate + 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide = tetrahydrofolate + 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4- carboxamide and IMP + H2O = 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4- carboxamide.

Glycine hydroxymethyltransferase precursor; 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.

5-phosphoribosylglycinamide formyltransferase (phosphoribosylglycinamide formyltransferase); Catalyzes the transfer of a formyl group from 10- formyltetrahydrofolate to 5-phospho-ribosyl-glycinamide (GAR), producing 5-phospho-ribosyl-N-formylglycinamide (FGAR) and tetrahydrofolate.

Methionine synthase (5-methyltetrahydrofolate:L-homocysteine S-methyltransferase); Catalyzes the transfer of a methyl group from methyl- cobalamin to homocysteine, yielding enzyme-bound cob(I)alamin and methionine. Subsequently, remethylates the cofactor using methyltetrahydrofolate.

Glycine cleavage system T protein, aminomethyltransferase; S-Aminomethyldihydrolipoylprotein + Tetrahydrofolate <=> Dihydrolipoylprotein + 5,10-Methylenetetrahydrofolate + NH3.

Methionyl-tRNA formyltransferase; Attaches a formyl group to the free amino group of methionyl- tRNA(fMet). The formyl group appears to play a dual role in the initiator identity of N-formylmethionyl-tRNA by promoting its recognition by IF2 and preventing the misappropriation of this tRNA by the elongation apparatus; Belongs to the Fmt family.

Dihydrofolate reductase; 5,6,7,8-tetrahydrofolate + NADP+ = 7,8-dihydrofolate + NADPH. tetrahydrofolate biosynthesis; tetrahydrofolate from 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine diphosphate and 4-aminobenzoate: step 3/3.

Phosphoribosylformylglycinamidine synthase II (FGAM synthase II); Part of the phosphoribosylformylglycinamidine synthase complex involved in the purines biosynthetic pathway. Catalyzes the ATP-dependent conversion of formylglycinamide ribonucleotide (FGAR) and glutamine to yield formylglycinamidine ribonucleotide (FGAM) and glutamate. The FGAM synthase complex is composed of three subunits. PurQ produces an ammonia molecule by converting glutamine to glutamate. PurL transfers the ammonia molecule to FGAR to form FGAM in an ATP- dependent manner. PurS interacts with PurQ and PurL and is [...]