Table 2.
Total distribution of virulence genes in B. cereus strains collection (n = 174) isolated from foodstuffs in Tunisia
| Toxigenic genes | No. (%) of strains positive for target gene(s) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Cooked food (n = 42) | Pastry products (n = 37) | Cereal products (n = 23) | Cooked poultry meat (n = 18) | Spices (n = 17) | Seafood products (n = 11) | Canned products (n = 9) | Raw poultry meat (n = 8) | Fresh-cut vegetables (n = 5) | Dairy products (n = 4) | Total (n = 174) | |
| HBL gene complexes | |||||||||||
| hblC | 1 (2.4) | 4 (10.8) | 1 (4.3) | 1(5.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 7 (4.0) |
| hblD | 3 (7.1) | 0 (0.0) | 1(4.3) | 0 (0.0) | 1 (5.9) | 1 (9.1) | 0 (0.0) | 2 (25.0) | 0 (0.0) | 0 (0.0) | 8 (4.6) |
| hblA+ hblC | 1 (2.4) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.6) |
| hblC+ hblD | 7 (16.7) | 8 (21.6) | 2 (8.7) | 0 (0.0) | 0 (0.0) | 1 (9.1) | 2 (22.2) | 0 (0.0) | 3 (60.0) | 1 (25.0) | 24 (13.8) |
| hblA+ hblC+ hblD | 5 (11.9) | 4(10.8) | 2 (8.7) | 3 (16.7) | 7 (41.2) | 4 (36.4) | 0 (0.0) | 1 (12.5) | 1 (20.0) | 0 (0.0) | 27 (15.5) |
| hblB+ hblC+ hblD | 2 (4.8) | 3 (8.1) | 1(4.3) | 2 (11.1) | 1 (5.9) | 1 (9.1) | 1 (11.1) | 1 (12.5) | 0 (0.0) | 0 (0.0) | 12 (6.9) |
| hblA+ hblB+ hblC+ hblD | 6 (14.3) | 8 (21.6) | 5 (21.8) | 2(11.1) | 3 (17.6) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 24 (13.8) |
| None detected | 17 (40.4) | 10 (27.0) | 11 (47.8) | 10 (55.6) | 5 (29.4) | 4 (36.4) | 6 (66.7) | 4 (50.0) | 1 (20.0) | 3 (75.0) | 71 (40.8) |
| NHE gene complexes | |||||||||||
| nheA | 1 (2.4) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.6) |
| nheB | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (5.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.6) |
| nheA+ nheB | 9 (21.4) | 4(10.8) | 1(4.3) | 1(5.6) | 1 (5.9) | 2 (18.2) | 0 (0.0) | 3 (37.5) | 0 (0.0) | 1 (25.0) | 22 (12.6) |
| NheA+ nheC | 2 (4.8) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (1.1) |
| nheB+ nheC | 1 (2.4) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.6) |
| nheA+ nheB+ nheC | 29 (69.0) | 33 (89.2) | 22 (95.7) | 17 (94.4) | 15 (88.2) | 9 (81.8) | 9 (100.0) | 5 (62.5) | 5 (100.0) | 3 (75.0) | 147 (84.5) |
| None detected | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Other genes | |||||||||||
| cytK | 13 (30.1) | 15 (40.54) | 9 (39.1) | 6 (33.3) | 9 (52.9) | 8 (72.7) | 3 (33.3) | 1 (12.5) | 1 (20.0) | 1 (25.0) | 66 (37.9) |
| bceT | 17 (40.4) | 20 (54.1) | 14 (60.9) | 9 (50.0) | 10 (58.8) | 10 (90.9) | 2 (22.2) | 5 (62.5) | 1 (20.0) | 0 (0.0) | 88 (50.6) |
| ces | 2 (4.8) | 1 (2.7) | 0 (0.0) | 3 (16.7) | 1 (5.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 7 (4.0) |