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- *************************************************************
- * Phosphoglycerate mutase family phosphohistidine signature *
- *************************************************************
-
- Phosphoglycerate mutase (EC 5.4.2.1) (PGAM) and bisphosphoglycerate mutase
- (EC 5.4.2.4) (BPGM) are structurally related enzymes which catalyze reactions
- involving the transfer of phospho groups between the three carbon atoms of
- phosphoglycerate [1,2]. Both enzymes can catalyze three different reactions,
- although in different proportions:
-
- - The isomerization of 2-phosphoglycerate (2-PGA) to 3-phosphoglycerate (3-
- PGA) with 2,3-diphosphoglycerate (2,3-DPG) as the primer of the reaction.
- - The synthesis of 2,3-DPG from 1,3-DPG with 3-PGA as a primer.
- - The degradation of 2,3-DPG to 3-PGA (phosphatase EC 3.1.3.13 activity).
-
- In mammals, PGAM is a dimeric protein. There are two isoforms of PGAM: the M
- (muscle) and B (brain) forms. In yeast, PGAM is a tetrameric protein. BPGM is
- a dimeric protein and is found mainly in erythrocytes where it plays a major
- role in regulating hemoglobin oxygen affinity as a consequence of controlling
- 2,3-DPG concentration.
-
- The catalytic mechanism of both PGAM and BPGM involves the formation of a
- phosphohistidine intermediate [3].
-
- The bifunctional enzyme 6-phosphofructo-2-kinase / fructose-2,6-bisphosphatase
- (EC 2.7.1.105 and EC 3.1.3.46) (PF2K) [4] catalyzes both the synthesis and the
- degradation of fructose-2,6-bisphosphate. PF2K is an important enzyme in the
- regulation of hepatic carbohydrate metabolism. Like PGAM/BPGM, the fructose-
- 2,6-bisphosphatase reaction involves a phosphohistidine intermediate and the
- phosphatase domain of PF2K is structurally related to PGAM/BPGM.
-
- We built a signature pattern around the phosphohistidine residue.
-
- -Consensus pattern: [LIVM]-x-R-H-G-[EQ]-x(3)-N
- [H is the phosphohistidine residue]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: yeast hypothetical protein YKL128c.
-
- -Note: some organisms harbor a form of PGAM independent of 2,3-DPG, this
- enzyme is not related to the family described above [5].
-
- -Last update: June 1994 / Text revised.
-
- [ 1] Le Boulch P., Joulin V., Garel M.-C., Rosa J., Cohen-Solal M.
- Biochem. Biophys. Res. Commun. 156:874-881(1988).
- [ 2] White M.F., Fothergill-Gilmore L.A.
- FEBS Lett. 229:383-387(1988).
- [ 3] Rose Z.B.
- Meth. Enzymol. 87:43-51(1982).
- [ 4] Bazan J.F., Fletterick R.J., Pilkis S.J.
- Proc. Natl. Acad. Sci. U.S.A. 86:9642-9646(1989).
- [ 5] Grana X., De Lecea L., El-Maghrabi M.R., Urena J.M., Caellas C.,
- Carreras J., Puigdomenech P., Pilkis S.J., Climent F.
- J. Biol. Chem. 267:12797-12803(1992).
-