TABLE 1.
Characteristics of Clostridium botulinum groups I and II
| Characteristic | C. botulinum group I | C. botulinum group II | Reference(s) |
|---|---|---|---|
| Toxinotypes | A, AB, B, BF, F | B, E, F | 197 |
| Strain origin | Soil | Aquatic environments | 34, 98, 106, 123, 126, 151, 194, 195, 208, 220, 222 |
| Genome size (Mbp) | 3.9-4.1 | 3.6-4.1 | 96, 130 |
| GC content (%) of genome | 26-28 | 26-28 | 115, 127, 128 |
| Genetic diversity | Narrow | Wide | 96, 110, 130, 159, 160 |
| Utilization of proteins as energy source | Yes | No | 35 |
| Carbohydrate fermentation | Glucose, fructose, maltose, salicin, sorbitol | Amygdalin, dextrin, fructose, galactose, glucose, glycogen, maltose, mannose, melezitose, ribose, sorbitol, starch, sucrose, trehalose | 35, 132, 197 |
| Metabolite production | Acetic, butyric, isobutyric, isovaleric, isocaproic, propionic, and valeric acids; alcohols; hydrogen sulfide | Acetic, butyric, formic, succinic, and lactic acids | 197 |
| Bacteriocin production | Boticin | NRa | 51, 125 |
| Colony morphology on blood agar | 2—6 mm (diam); irregular margin; opaque, raised center; narrow hemolysis | 1-3 mm (diam); slightly irregular with lobate margins; translucent to semiopaque with matt surface; mosaic structure in oblique light; narrow hemolysis | 35, 197 |
| Colony morphology on egg yolk agar (lipase reaction) | Iridescent layer on and around colonies | Iridescent layer on and around colonies | 197 |
| Susceptibility to antibioticsb | Susceptible to erythromycin, metronidazole, penicillin, rifampin, tetracycline; resistant to cycloserine, gentamicin, nalidixic acid, sulfamethoxazole, trimethoprim | Susceptible to erythromycin, metronidazole, penicillin, rifampin, chloramphenicol, clindamycin, tetracycline, trimethoprim; resistant to gentamicin, nalidixic acid, cephalotin, sulfamethoxazole | 204 |
| Minimum/optimum growth temp (°C) | 10/35-37 | 3/26-30 | 56, 57, 83, 139, 180, 181, 197, 202 |
| Growth-limiting pH | 4.3-4.5 | 5.0-5.1 | 185, 193 |
| Growth-limiting NaCl in water phase (%) | 10 | 5 | 197 |
| Heat resistance of spores | High (D121-110°C,c 0.15-1.8 min) | Moderate (D85°C,c 1-98 min) | 112, 135, 139, 140, 168-170, 184, 192 |
| Typical vehicle foods for botulism | For food-borne botulism, vegetables, meat, and canned foods; for infant botulism, honey | For food-borne botulism, fish, meat, and minimally processed packaged foods; for infant botulism, NR | 93a, 134 |
a
NR, not reported.
b
Based on information on C. botulinum type A and E strains (204).
c
DT, decimal reduction time at temperature T.