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. Author manuscript; available in PMC: 2009 Jun 29.
Published in final edited form as: Proc West Pharmacol Soc. 2008;51:30–34.

Figure 3.

Figure 3

Inhibition of NDPK-B activity by PC-3 generated angiostatin but not by commercial angiostatin. Partially purified NDPK-B was incubated with ADP and GTP in the presence of either commercial angiostatin (Angiogenesis Research, Inc.) or PC-3 derived angiostatin and the resultant ATP measured by luminescence assay. Addition of PC-3 angiostatin resulted in a significant reduction in Vmax (p < 0.05) but no change in substrate affinity (Km) which suggests that angiostatin acts as a non-competitive inhibitor. Neither freeze-thaw nor different lot preparation of commercial angiostatin could explain the absence of activity. Data are presented as mean ± SEM, n=3. Inset: Western blot of PC-3 conditioned media with a polyclonal antibody (Ab-1) against purified human angiostatin protein. Immunopositive bands at 40–45 kDa were present in the conditioned media incubated with plasminogen (PC3-HPg) but absent in control media (PC3-CON), human plasminogen (HPg), and bovine serum albumin (BSA). These bands were identical to those present in commercial angiostatin (AS).