Table II.
Steady-State Kinetic Constants for TcUGM and TcUGM Mutant Enzymes
| Protein | kcat (s−1) | KM (µM) | kcat/KM (s−1 M−1) | Relative (kcat/KM)a |
|---|---|---|---|---|
| TcUGMa | 13.4 ± 0.3 | 140 ± 10 | 93 ± 6 | 1.0 ± 0.1 |
| R176A | 0.0223 ± 0.0003 | 134 ± 6 | 0.167 ± 0.005 | 0.0018 ± 0.0001 |
| R327A | 4.2 ± 0.4 | 90 ± 30 | 47.1 ± 13.8 | 0.5 ± 0.2 |
| Y395F | 0.247 ± 0.037 | 91 ± 49 | 2.7 ± 1.5 | 0.03 ± 0.02 |
| Y429F | 6.29 ± 0.14 | 100 ± 7 | 63 ± 5 | 0.68 ± 0.07 |
| Y317F | 0.290 ± 0.013 | 334 ± 38 | 0.87 ± 0.1 | 0.009 ± 0.001 |
Data from Oppenheimer et al.36
a
(kcat/KM of mutant)/(kcat/KM of TcUGM).