| IPP1 | nucleocytosolic inorganic pyrophosphatase from S. cerevisiae |
| PPi | inorganic pyrophosphate |
| PPase | inorganic pyrophosphatase |
| m-PPase | membrane-bound ion-translocating inorganic pyrophosphatase |
| MVP | Na+-translocating m-PPase from the archaea Methanosarcina mazei |
| OD660 | optical density at 660 nm |
| PPA1 | cytosolic inorganic pyrophosphatase from Homo sapiens |
| sPPase | soluble inorganic pyrophosphatases |
| SPP2 | inorganic pyrophosphatase from S. mutans |
| yEGFP | yeast-enhanced green fluorescent protein |