Acylphosphatase Explained

In enzymology, an acylphosphatase is an enzyme that catalyzes the hydrolysis of the carboxyl-phosphate bond of acylphosphates, with acylphosphate and H₂O as the two substrates of this enzyme, and carboxylate and phosphate as its two products:^[1]

Function

This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides in phosphorus-containing anhydrides. The systematic name of this enzyme class is acylphosphate phosphohydrolase. Other names in common use include acetylphosphatase, 1,3-diphosphoglycerate phosphatase, acetic phosphatase, Ho 1-3, and GP 1-3.

This enzyme participates in 3 metabolic pathways:

• glycolysis / gluconeogenesis
• pyruvate metabolism, and
• benzoate degradation via coa ligation.

Structural studies

Structures of this enzyme have been solved by both NMR and X-ray crystallography. See the links to PDB structures in the info boxes on the right for a current list of structures available in the PDB. The protein contains a beta sheet stacked on two alpha helices described by CATH as an Alpha-Beta Plait fold. The active site sits between sheet and helices and contains an arginine and an asparagine.^[2] Most structures are monomeric ^[3]

Isozymes

Humans express the following two acylphosphatase isozymes:

acylphosphatase 1, erythrocyte (common) type Hgncid: 179 Symbol: ACYP1 Entrezgene: 97 Omim: 600875 Refseq: NM_001107 Uniprot: P07311 Ecnumber: 3.6.1.7 Chromosome: 14 Arm: q Band: 24.3

acylphosphatase 2, muscle type Hgncid: 180 Symbol: ACYP2 Entrezgene: 98 Omim: 102595 Refseq: NM_138448 Uniprot: P14621 Ecnumber: 3.6.1.7 Chromosome: 2 Arm: p Band: 16.2

Notes and References

1. Stefani M, Taddei N, Ramponi G . Insights into acylphosphatase structure and catalytic mechanism . Cell. Mol. Life Sci. . 53 . 2 . 141–51 . February 1997 . 9118002 . 10.1007/PL00000585 . 24072481 . 11147357 .
2. Gribenko AV, Patel MM, Liu J, McCallum SA, Wang C, Makhatadze GI . Rational stabilization of enzymes by computational redesign of surface charge-charge interactions . Proceedings of the National Academy of Sciences of the United States of America . 106 . 8 . 2601–6 . February 2009 . 19196981 . 2650310 . 10.1073/pnas.0808220106 . 2009PNAS..106.2601G . free .
3. Web site: Enzyme 3.6.1.7 . PDBe Enzyme Browser .