Figure 2.

polyP-dependent NDK activity in the E. coli membrane fraction. The reaction mixture (10 μl) containing the membrane fraction, PPK buffer, 1 mM NDP, and 0.1 mM [³²P]polyP was incubated at 37°C for 40 min. E. coli membrane fractions from MG1655 (wild type; 1.6 μg) and Δppk ppx mutant (2.1 μg) were used. The TLC plates were developed with (A) 1.5 M KH₂PO₄ (pH 3.5) and (B) 0.75 M KH₂PO₄ (pH 3.5).