Table 2.
SEA production capability of 29 sea-positive Staphylococcus aureus in terms of amount of SEA per hour in the log growth phase and after 24 h of cultivation
| Strains | ST | SE profile | Source | Phage | CFU (×108/mL) | SEA (ng/108 CFU) | Total SEA (ng/mL, 24 h) | Expression ratio at the log growth phase | ||
|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||
| 6 h | 24 h | Per hour at the log growth phase | 24 h | |||||||
| SA-2 | ST188 | A | Dairy | ФSa3ms | 16.2 | 33.2 | 0.1 | 1.1 | 36 | Baseline |
| SA-16 | ST6 | A | Meat | ФSa3ms | 21.1 | 36.1 | 2.1 | 11.2 | 404 | 3.2 |
| SA-19 | ST188 | A | Dairy | ФSa3ms | 19.0 | 37.0 | 0.6 | 2.1 | 77 | 3.1 |
| SA-56 | ST6 | AC | Meat | ФSa3ms | 18.1 | 34.6 | 1.5 | 5.9 | 204 | 5.6 |
| SA-83 | ST6 | AC | Meat | ФSa3ms | 16.0 | 31.1 | 1.2 | 4.1 | 128 | 1.7 |
| SA-112 | ST1 | AC | Meat | ФSa3ms | 31.1 | 43.0 | 3.1 | 8.3 | 357 | 1.0 |
| SA-148 | ST1 | ABD | Meat (SFP) | ФSa3ms | 14.5 | 30.5 | 2.8 | 8.1 | 247 | 2.2 |
| SA-187 | ST59 | ABC | Patient | ФMu3A | 24.0 | 41.1 | 0.1 | 2.0 | 82 | 1.4 |
| SA-189 | ST59 | A | Dairy | ФMu3A | 18.0 | 33.2 | 0.2 | 3.2 | 106 | 1.4 |
| SA-212 | ST6 | AC | Dairy | ФSa3ms | 16.1 | 34.9 | 11.1 | 30 | 1,047 | 9.8 |
| SA-217 | ST15 | A | Dairy | ФSa3ms | 14.2 | 33.1 | 12 | 33.5 | 1,109 | 14.1 |
| SA-227 | ST59 | AB | Patient | ФMu3A | 22.0 | 39.0 | 0.2 | 3.5 | 136 | 1.1 |
| SA-230 | ST5 | A | Patient | ФMu3A | 17.9 | 33.5 | 1.3 | 7.1 | 238 | 2.7 |
| SA-239 | ST6 | A | Meat | ФSa3ms | 19.2 | 36.7 | 0.3 | 3.7 | 136 | 1.2 |
| SA-240 | ST1 | A | Meat | ФSa3ms | 19.1 | 36.8 | 1.2 | 6.7 | 247 | 1.4 |
| SA-253 | ST1 | AC | Dairy | ФSa3ms | 20.0 | 35.6 | 0.4 | 7.0 | 249 | 2.3 |
| SA-254 | ST1 | AC | Dairy | ФSa3ms | 19.0 | 32.0 | 2.9 | 9.2 | 294 | 6.8 |
| SA-255 | ST1 | AC | Dairy | ФSa3ms | 18.8 | 34.1 | 1.2 | 8.1 | 276 | 2.5 |
| SA-256 | ST1 | AC | Meat | ФSa3ms | 16.0 | 33.2 | 0.5 | 5.2 | 173 | 2.6 |
| SA-262 | ST5 | AC | Patient | ФMu3A | 15.0 | 32.9 | 1.3 | 5.4 | 178 | 1.9 |
| SA-265 | ST1 | A | Meat | ФSa3ms | 11.2 | 26.6 | 0.4 | 4.5 | 120 | 2.4 |
| SA-282 | ST1 | AB | Dairy | ФSa3ms | 9.8 | 25.3 | 3.1 | 8.9 | 225 | 3.5 |
| SA-283 | ST1 | AB | Dairy | ФSa3ms | 11.0 | 26.1 | 2.0 | 7.8 | 204 | 2.8 |
| SA-284 | ST1 | AB | Dairy | ФSa3ms | 8.8 | 21.1 | 1.7 | 6.1 | 129 | 3.1 |
| SA-335 | ST1 | A | Meat | ФSa3ms | 18.0 | 38.0 | 3.9 | 10.1 | 384 | 2.1 |
| SA-337 | ST239 | A | Patient | ФMu3A | 22.3 | 39.2 | 1.1 | 5.1 | 200 | 3.1 |
| SA-340 | ST239 | A | Patient | ФMu3A | 29.9 | 41.0 | 7.2 | 21.4 | 877 | 10.1 |
| SA-341 | ST239 | A | Patient | ФMu3A | 26.7 | 42.1 | 4.1 | 18.1 | 762 | 6.9 |
| ФSa3ms | ||||||||||
| SA-346 | ST1 | A | Meat | ФSa3ms | 16.7 | 35.9 | 1.2 | 6.1 | 219 | 1.8 |
| Mean | 18.26 | 34.37 | 2.37 | 8.74 | 305 | 3.64 | ||||
| SD | 5.26 | 5.12 | 3.06 | 7.70 | 281 | 3.17 | ||||
| Maximum | 31.1 | 43.0 | 12.0 | 33.5 | 1,109 | 14.1 | ||||
| Minimum | 8.8 | 21.1 | 0.1 | 2.0 | 36 | 1.0 | ||||
Abbreviations: CFU, colony-forming unit; SE, staphylococcal enterotoxin; SEA, staphylococcal enterotoxin A; SFP, staphylococcal food poisoning; ST, sequence type.