TABLE 3.
Apparent kinetic constants for the reaction of LCAT with rHDL made with WT apoA-I or one of the apoA-I mutant forms
| Apparent Km (μM) | Apparent Vmax (nmol CE/h/ml LCAT) | Apparent Vmax/Km (nmol CE/h/ml LCAT/μM) | |
| WT apoA-I | 2.3 ± 0.4 | 977 ± 46 | 437 ± 30 |
| apoA-I[R123A] | 3.3 ± 0.6 | 270 ± 18a | 81 ± 9a |
| apoA-I[R123E] | 4.1 ± 0.5b | 235 ± 33a | 59 ± 8a |
| apoA-I[R131A] | 1.3 ± 0.3 | 923 ± 61 | 704 ± 147 |
The values represent the mean ± SD of at least three independent measurements. The apparent LCAT kinetic parameters were determined from the CE formation assays using Lineweaver-Burk plots (double reciprocal plots) of reaction velocity versus rHDL cholesterol concentration as described in the Material and Methods.
a
P < 0.0005 compared with the values for WT apoA-I.
b
P < 0.05 compared with the values for WT apoA-I.