The function of PPA2 (inorganic pyrophosphatase 2, ENSG00000138777) is as follows. Hydrolyzes inorganic pyrophosphate (PubMed:27523597). This activity is essential for correct regulation of mitochondrial membrane potential, and mitochondrial organization and function (PubMed:27523598). {ECO:0000269|PubMed:27523597, ECO:0000269|PubMed:27523598}.