Abstract
Bacteria take up phosphate (Pi) from the medium through two transport systems, the main one is the Pst system. The Pst system is encoded by a five-genes operon, the first four genes, pstS, pstC, pstA and pstB encode proteins that are actively involved in Pi transport. The function of the fifth and most distal gene, phoU, has not yet been elucidated. Inorganic polyphosphate (PolyP) is a li…