Table 3 Differences in the number of virulence factors between clinical and environmental isolates
Virulence class (number of related genes) | Environmental isolates (n = 11) | Clinical isolates (n = 15) | ||
|---|---|---|---|---|
Virulence genes | Per strain (%)a | Virulence genes | Per strain (%)a | |
Acid resistance (n = 2) | 0 | 0 | 2 | 0.13 |
Adherence (n = 51) | 202 | 18.36 | 277 | 18.47 |
Anaerobic respiration (n = 1) | 0 | 0 | 1 | 0.07 |
Antiphagocytosis (n = 32) | 158 | 14.36 | 233 | 15.53 |
Chemotaxis and motility (n = 56) | 593 | 53.91 | 818 | 54.53 |
Copper uptake (n = 1) | 0 | 0 | 1 | 0.07 |
Endotoxin (n = 2) | 1 | 0.09 | 1 | 0.07 |
Enzyme (n = 7) | 11 | 1 | 20 | 1.33 |
Immune evasion (n = 6) | 11 | 1 | 19 | 1.27 |
Intracellular survival (n = 2) | 0 | 0 | 1 | 0.07 |
Invasion (n = 1) | 0 | 0 | 1 | 0.07 |
Iron uptake (n = 25) | 166 | 15.09 | 227 | 15.13 |
Quorum sensing (n = 2) | 10 | 0.91 | 15 | 1 |
Regulation (n = 2) | 0 | 0 | 2 | 0.13 |
Secretion system (n = 86) | 145 | 13.18 | 182 | 12.13 |
Serum resistance (n = 1) | 1 | 0.09 | 0 | 0 |
Stress adaptation (n = 2) | 1 | 0.09 | 1 | 0.07 |
Surface protein anchoring (n = 1) | 0 | 0 | 1 | 0.07 |
Toxin (n = 14) | 65 | 5.91 | 90 | 6 |
Others (n = 4) | 3 | 0.27 | 5 | 0.33 |