TABLE 3.
Rates of factor Xa-catalyzed inactivation and A1 subunit cleavage of factor VIIIa variants
Factor VIIIa A1 subunit cleavage rates were determined through nonlinear least squares regression analysis and presented in Fig. 1. Values represent mean ± S.D. from at least three separate determinations.
| Factor VIIIa | Factor VIIIa inactivation | A1 cleavage |
|---|---|---|
| nm FVIIIa/min/nm FXa | nm A1/min/nm FXa | |
| WT | 4.7 ± 0.7 (1.0)a | 5.4 ± 0.40 (1.0) |
| 336(P4-P2)372 | 1.5 ± 0.3 (0.3) | 1.0 ± 0.02 (0.2) |
| 336(P1′-P3′)372 | 12.5 ± 2.8 (2.7) | 22.0 ± 3.00 (4.1) |
| 336(P4-P3′)372 | 6.2 ± 0.9 (1.3) | 9.3 ± 1.80 (1.7) |
| 336(P4-P2)740 | 4.6 ± 0.7 (1.0) | 8.3 ± 1.00 (1.5) |
| 336(P1′-P3′)740 | 7.6 ± 1.6 (1.6) | 15.6 ± 2.90 (2.9) |
| 336(P4-P3′)740 | 25.2 ± 5.2 (5.4) | 30.2 ± 5.00 (5.6) |
| 336(P4-P3′)562 | 1.7 ± 0.4 (0.4) | 2.2 ± 0.30 (0.4) |
| Arg336Gln | 0.4 ± 0.1 (0.1) | NAb |
a Values in parentheses are rate values relative to wild type.
b NA, not applicable.