Table 4. Kinetic parameters of mutant and wild-type UDP-GlcDH from C. neoformans.
Equal amounts of recombinant protein were used in all assays. Km values for UDP-Glc were determined in the presence of 2 mM NAD+, with UDP-Glc varied from 0 to 5 mM; Km for NAD+ was determined in the presence of 10 mM UDP-Glc for wild-type and 2 mM UDP-Glc for mutants, with NAD varied from 0 to 2 mM. Results are expressed as means±S.E.M.
| Km (mM) | |||
|---|---|---|---|
| Mutation | kcat (s−1) | UDP-Glc | NAD+ |
| None | 2.7±0.1×10−1 | 1.5±0.1 | 0.1±0.01 |
| C278A | – | – | – |
| R43A | 5.5±0.2×10−3 | 0.4±0.03 | 0.8±0.2 |
| R348A | 2.8±0.1×10−2 | 0.4±0.04 | 0.4±0.04 |
| R262A | – | – | – |
| K341A | – | – | – |