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- * Phosphoribosylglycinamide formyltransferase active site *
- ***********************************************************
-
- Phosphoribosylglycinamide formyltransferase (EC 2.1.2.2) (GART) [1] catalyzes
- the third step in de novo purine biosynthesis, the transfer of a formyl group
- to 5'-phosphoribosylglycinamide. In higher eukaryotes, GART is part of a
- multifunctional enzyme polypeptide that catalyzes three of the steps of purine
- biosynthesis. In bacteria and yeast, GART is a monofunctional protein of about
- 200 amino-acid residues.
-
- In the Escherichia coli enzyme, an aspartic acid residue has been shown to be
- involved in the catalytic mechanism. The region around this active site
- residue is well conserved in GART from prokaryotic and eukaryotic sources and
- can be used as a signature pattern.
-
- Mammalian formyltetrahydrofolate dehydrogenase (EC 1.5.1.6) [2] is a cytosolic
- enzyme responsible for the NADP-dependent decarboxylative reduction of
- 10-formyltetrahydrofolate into tetrahydrofolate. It is a protein of about
- 900 amino acids consisting of three domains; the N-terminal domain (200
- residues) is structurally related to GARTs.
-
- Escherichia coli methionyl-tRNA formyltransferase (EC 2.1.2.9) (gene fmt) [3]
- is the enzyme responsible for modifying the free amino group of the aminoacyl
- moiety of methionyl-tRMA(fMet). The central part of fmt seems to be
- evolutionary related to GART's active site region.
-
- -Consensus pattern: G-x-[STM]-[IVT]-x-[FYWVQ]-[VMAT]-x-[DEVM]-x-[LIVM]-D-x-G-
- x(2)-[LIT]-x(6)-[LIVM]
- [D is the active site residue]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: December 1992 / Pattern and text revised.
-
- [ 1] Inglese J., Smith J.M., Benkovic S.J.
- Biochemistry 29:6678-6687(1990).
- [ 2] Cook R.J., Lloyd R.S., Wagner C.
- J. Biol. Chem. 266:4965-4973(1991).
- [ 3] Guillon J.-M., Mechulam Y., Schmitter J.-M., Blanquet S., Fayat G.
- J. Bacteriol. 174:4294-4301(1992).
-