Table 2.

Comparison of polyP-utilizing activity of PPK2 and several PPK1s

Vmax, ×107 pmol⋅min−1⋅mg−1Utilization/synthesis of poly PGDP/ADPPoly P750/poly P15
P. aeruginosa PPK250751.10.1
P. aeruginosa PPK10.0510.250.0312
E. coli PPK10.370.0730.01511
V. cholerae PPK19.5590.00016ND
H. pylori PPK112410.00046ND
  • * For PPK2, poly P15 (Sigma) and GDP were used as a donor and an acceptor, respectively. For PPK1, poly P750 and ADP were used as a donor and an acceptor, respectively.

  • The Vmax values for poly P-utilizing reactions divided by that for poly P-synthesizing reactions. For determining the Vmax value for poly P-synthesizing reaction of PPK2, GTP and Mn2+ instead of Mg2+ were used as a donor and a divalent cation, respectively. For determining the Vmax value for poly P-synthesizing reaction of PPK1, ATP was used as a donor. For more details, see accompanying report (11).

  • The Vmax value with GDP divided by that with ADP. Poly P15 (Sigma) or poly P750 was used for determining Vmax values for PPK2 or PPK1, respectively.

  • § The Vmax value with poly P750 divided by that with poly P15 (Sigma). GDP was used as an acceptor for PPK2; ADP was used for PPK1.

  • Data from Ahn and Kornberg (32).

  • Data from Ogawa et al. (31).

  • ** Not determined.