TABLE 2.
Kinetic parameters with error estimations for the Spc-SH3 D48G mutant under different buffer conditions at 25°C
| pH | Method | m‡-F (M−1) | m‡-U (M−1) | k‡-F (s−1) | k‡-U (s−1) |
|---|---|---|---|---|---|
| 50 mM phosphate pH 7.0 | Global fitting | 0.42* | −0.80 ± 0.03 (4%) | 0.00160 ± 0.00036 (22%) | 69 ± 9 (13%) |
| Individual fitting | 0.42* | −0.79 ± 0.03 (4%) | 0.00165 ± 0.00012 (8%) | 71 ± 8 (12%) | |
| Average of mutant values | 0.42 ± 0.02 (4%) | −0.90 ± 0.02 (4%) | |||
| 50 mM glycine pH 3.5 | Individual fitting | 0.50 ± 0.06 (12%) | −1.20 ± 0.09 (8%) | 0.08 ± 0.02 (25%) | 50 ± 7 (14%) |
| Average of mutant values | 0.52 ± 0.06 (12%) | −1.24 ± 0.09 (8%) | |||
| 50 mM glycine pH 2.5 | Individual fitting | 0.37 ± 0.03 (8%) | −0.92 ± 0.18 (20%) | 0.94 ± 0.18 (19%) | 11.6 ± 1.5 (13%) |
| Average of mutant values | 0.39 ± 0.06 (15%) | −0.96 ± 0.09 (9%) |
Errors are calculated as 3σx, where σx is the fitting or averaging error of x. Values in parentheses represent the relative errors calculated as (3σx/x) × 100.
*
Value fixed in the least-squares fitting.