Comparison of omptin activity toward glycosylated and nonglycosylated forms of TFPI. The omptin-positive bacterial strains: (A) E coli MC4100, (B) S Typhimurium ΔgalETK, or (C) Y pestis Kim5 were incubated with 30 nM glycosylated TFPI (SK-TFPI) derived from SK-Hepatoma cells (●) or nonglycosylated TFPI derived from E coli (○) for 30 minutes at room temperature at the indicated bacterial concentrations (x-axis). Samples were tested in clotting assays using normal plasma, with TFPI activities determined by reference to standard curves as in Figure 3A. Data are mean plus SEM (n = 3).