Polyphosphatase activity as well as phosphatase activity of rh-TRAP after co-precipitation with anti-TRAP antibodies.

The rh-TRAP was separated from Sf9 cell culture supernatant by co-precipitation with anti-TRAP antibodies (15A4 and 13B9). Polyphosphatase activity was also measured using [32P]poly(P)40 (0.346 mM) as substrate. Phosphatase activity was measured using pNPP as substrate. These activities were evaluated using the supernatant fraction (Sup.) or the pellet fractions (Pellet) after co-precipitation with anti-TRAP antibodies, 15A4 or 13B9. Values are expressed as means±SD of the percentage from three independent experiments comparing with the activities of Sf9 cell culture supernatant before co-precipitation as 100%. *p<0.05, significantly different from polyphosphatase activity of buffer. **p<0.05, significantly different from polyphosphatase activity of Sup. (15A4). ***p<0.05, significantly different from polyphosphatase activity of Sup. (15B9). #p<0.001, significantly different from phosphatase activity of buffer. ##p<0.001, significantly different from phosphatase activity of Sup. (15A4). ###p<0.001, significantly different from phosphatase activity of Sup. (13B9). (Student's t-test).