Phosphatase Fold HP
Phosphatase Classification: Fold HP
The HP (histidine phosphatase) fold has several enzymatic activities, including phosphatase and phosphoglycerate mutase (PGM) activity. The mutase activity transfers a phosphate within an intermediate of glycolysis. Both activities require a catalytic histidine which is phosphorylated during catalysis [1], hence the histidine phosphatase name. For a complete list of functions characterized members in the superfamily see Table 1 and Table S1 in [2]. HPs are found in both prokaryotes and eukaryotes.
Naming: histidine phosphatase (HP) or phosphoglycerate mutase (PGM)
The earliest and arguably best studied members of this group of genes primarily function as mutates, which results in naming them PGM. However, most if not all of later discoveries have been phosphatase activities of one kind or another [1]. To reflect this fact, we call it histidine phosphatase rather than phosphoglycerate mutase, although the genes are sometimes referred as PGM in the literature and in the SCOP database.
Superfamilies and families
The fold HP has a single superfamily HP, which consists of two families based upon sequence similarity [1]:
This classification is largely the same with Pfam classification.
Traditional classification
Traditionally, HP/PGM is classified as below [3, 4]:
- Monophosphoglycerate mutase (mPGM) - catalyzes the interconversion of 3-phosphoglycerate (3PGA) and 2-phosphoglycerate (2PGA)
- dependent on 23PGA as a cofactor (dPGM) - found in animal, fungi, and bacteria
- independent of 23PGA as a cofactor (iPGM) - found in plants, and bacteria
- Bisphosphoglycerate mutase (bPGM) - catalyzes primarily the interconversion of 1,3-phosphoglycerate (13PGA) and 23PGA
Pfam
HP corresponds to histidine phosphatase superfamily in Pfam database. It contains two families: branch 1 and branch 2. Branch 1 includes dPGMs, branch 2 includes histidine acid phosphatase. Branch 1 is largely dPGM.
SCOP
HP corresponds to SCOP fold phosphoglycerate mutase-like (c.60). It contains single superfamily, which include the families below:
- c.60.1.1: Cofactor-dependent phosphoglycerate mutase
- c.60.1.2: Histidine acid phosphatase
- c.60.1.4: 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, phosphatase domain
c60.1.1 and c60.1.4 forms dPGM.
References
- Rigden DJ. The histidine phosphatase superfamily: structure and function. Biochem J. 2008 Jan 15;409(2):333-48. DOI:10.1042/BJ20071097 |
- Jedrzejas MJ. Structure, function, and evolution of phosphoglycerate mutases: comparison with fructose-2,6-bisphosphatase, acid phosphatase, and alkaline phosphatase. Prog Biophys Mol Biol. 2000;73(2-4):263-87. DOI:10.1016/s0079-6107(00)00007-9 |
- Rigden DJ, Bagyan I, Lamani E, Setlow P, and Jedrzejas MJ. A cofactor-dependent phosphoglycerate mutase homolog from Bacillus stearothermophilus is actually a broad specificity phosphatase. Protein Sci. 2001 Sep;10(9):1835-46. DOI:10.1110/ps.15701 |
- Rigden DJ. The histidine phosphatase superfamily: structure and function. Biochem J. 2008 Jan 15;409(2):333-48. DOI:10.1042/BJ20071097 |
