Polyphosphate kinase (Ppk) catalyses the formation of polyphosphate from ATP, with chain lengths of up to a thousand or more orthophosphate molecules.

1: Transcription of ppk from Acinetobacter sp. strain ADP1, encoding a putative polyphosphate kinase, is induced by phosphate starvation. Geissdorfer W, Ratajczak A, Hillen W; Appl Environ Microbiol 1998;64:896-901. PMID:9501429