TABLE 2.
NbaA activities in cell-free extracts containing NbaA or its mutant proteins and effect of FMN on their activitiesa
| NbaA | Sp act
|
|||
|---|---|---|---|---|
| Without FMN
|
With FMN
|
|||
| Mean U/mgb ± SD | % | Mean U/mg ± SD | % | |
| Wild type | 10.26 ± 0.23 | 100 | 31.73 ± 0.37 | 100 |
| N40A | ND | ND | ||
| H63A | 7.44 ± 0.17 | 73 | 22.85 ± 0.33 | 72 |
| H69A | 0.20 ± 0.01 | 2 | 0.96 ± 0.03 | 3 |
| D76A | ND | ND | ||
| H110A | 3.38 ± 0.01 | 33 | 13.99 ± 0.38 | 44 |
| E113A | ND | ND | ||
a
FMN was added to the cell-free extracts containing NbaA and its mutants at a concentration of 5.0 mM, and it was preincubated for 5 min on ice prior to the assay. ND, not detected.
b
One unit is the amount (micromoles) of NADPH oxidized per minute. Results are the means of three independent experiments, with standard deviations noted.