Pyrophosphatase 1 (PPA1)

Inorganic pyrophosphates are generated as byproducts of many biosynthetic reactions, including DNA and RNA synthesis, fatty acid and amino acid activation, and cyclic nucleotide synthesis. Inorganic pyrophosphatases (EC 3.6.1.1), such as PPA1, maintain the thermodynamic favorability of these reactions by catalyzing the hydrolysis of pyrophosphates into organic phosphates, which are then exported across the cell membrane.

The deduced 289-amino acid protein has a calculated molecular mass of 32.7 kD and shares 94% amino acid identity with bovine pyrophosphatase. Northern blot analysis detected a 1.4-kb PPA1 transcript in all tissues examined. RNA dot blot analysis confirmed ubiquitous PPA1 expression.