Table 2. Genes and encoded proteins for polyP and PPi metabolism in O. anthropi DE2010



  Gene            GenBank          Gene product                                               Activity
              accession number

PolyP and PPi metabolisms

  ppk1          DNK03_06690        Polyphosphate kinase 1             Transfers the terminal phosphate residue of ATP to a
                                                                      growing chain of polyP in a reversible reaction.

   ppx          DNK03_06685        Exopolyphosphatase                 Mediates polyP degradation releasing orthophosphate
                                                                      from chain end.

  hppa          DNK03_06575        K+-insensitive pyrophosphate-      Proton transmembrane pump that utilizes the energy of
                                   energized proton pump              pyrophosphate hydrolysis as the driving force for
                                                                      proton movement.

ppx/gppa        DNK03_08775        Exopolyphosphatase/pppGpp          Hydrolyses guanosine pentaphosphate (pppGpp) to
                                   phosphohydrolase                   guanosine tetraphosphate (ppGpp).

  ppk2          DNK03_11830        Polyphosphate kinase 2             ppk2, at least in isolated form, seems to be designed for
                                                                      synthesis of GTP from polyP in contrast to ppk1, which
                                                                      strongly favors synthesis of polyP and exclusively from
                                                                      ATP.

   ppa          DNK03_19225        Inorganic pyrophosphatase          Inorganic pyrophosphatase (PPase) catalyzes the
                                                                      hydrolysis of inorganic pyrophosphate to form
                                                                      orthophosphate