title: Growth of group II Clostridium botulinum strains at extreme temperatures.
abstract: The minimum and maximum growth temperatures and the maximum growth rates at 10, 30, 37, and 40°C were determined for 24 group II Clostridium botulinum strains. Genetic diversity of the strains was revealed by amplified fragment length polymorphism (AFLP) analysis. The minimum  growth temperatures ranged from 6.2 to 8.6°C, and the maximum growth temperatures ranged from 34.7 to 39.9°C. The mean maximum growth temperatures and mean maximum growth rates of type E strains at 37°C were significantly higher than those of type B and type F strains. A significant  correlation between maximum growth rates at 37°C and maximum growth temperatures was found for all strains. Some type E strains with a high minimum growth temperature also had a higher maximum growth rate at 37°C than at 30°C, which suggests that some group II C. botulinum  strains are more mesophilic in their growth properties than others. We found relatively small differences between AFLP clusters, indicating that diverse genetic background among the strains was not reflected in the growth properties. The growth characteristics of group II C. botulinum  and some type E strains with mesophilic growth properties may have an impact on inoculation studies and predictive modeling for assessing the safety of foods.
authors: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, P.O. Box 66 (Agnes Sjöbergin katu 2), 00014 University of Helsinki, Helsinki, Finland. yagmur.derman@helsinki.fi
authors: Yağmur
authors: Y
authors: Derman
authors: Miia
authors: M
authors: Lindström
authors: Katja
authors: K
authors: Selby
authors: Hannu
authors: H
authors: Korkeala
mesh_terms: D001905:Botulinum Toxins / Q000096:biosynthesis*; D003014:Clostridium botulinum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D014644:Genetic Variation; D006801:Humans; D007700:Kinetics; D012150:Polymorphism, Restriction Fragment Length; D013696:Temperature
chemical_list: D001905:Botulinum Toxins