TABLE 5.
Cysteine protease activities in culture supernatants of SpeB-positive GAS isolated from invasive cases of varying severity
| Isolate source (n) | Enzyme activity (101 FU)a
|
Pb | |
|---|---|---|---|
| Mean ± SD | Median | ||
| Nonsevere infection (25) | 1,212 ± 47 | 1,140 | |
| Severe infection (32) | 1,054 ± 46.8 | 1,148 | 0.023 |
| STSS (10) | 908 ± 61.1 | 877 | 0.001 |
| NF (13) | 1,216 ± 34.6 | 1,200 | 0.950 |
| STSS + NF (9) | 982 ± 118.7 | 1,080 | 0.037 |
a
The enzyme activity of SpeB was determined by a fluorescent enzyme assay described in Materials and Methods.
b
Differences between the enzyme activities of SpeB produced by isolates from nonsevere cases and isolates from various subgroups of severe cases were evaluated by the Student t test.