Related Experiment Video
Updated: Jun 4, 2026
The Insect Galleria mellonella as a Powerful Infection Model to Investigate Bacterial Pathogenesis
Published on: December 11, 2012
Using an insect model to assess correlation between temperature and virulence in Bacillus weihenstephanensis and
Lotte Stenfors Arnesen1, Per Einar Granum, Christophe Buisson
1Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Section for Food Safety, Oslo, Norway. lotte.s.arnesen@nvh.no
Abstract:
The closely related bacterial species Bacillus cereus and Bacillus weihenstephanensis are adapted to the mesophilic and the psychrotrophic temperature range, respectively. While B. cereus strains are associated with foodborne diseases, B. weihenstephanensis strains are so far not, although similar virulence genes are found in both species. Our investigations show that both species were virulent in the insect model, Galleria mellonella, following infection via oral and haemocoel routes. However, virulence of B. weihenstephanensis was much higher at 15°C than at 37°C. Furthermore, a temperature-dependent difference between the species was seen in a cell culture cytotoxicity assay. In summary, our results demonstrate for the first time virulence of B. weihenstephanensis strains in an in vivo model. In addition, we found that G. mellonella is a useful model for studies of the psychrotolerant species of the B. cereus group, suggesting that insects might be an ecological growth niche for several members of this bacterial group.
