Limitations in the use of Drosophila melanogaster as a model host for gram-positive bacterial infection
Article first published online: 29 SEP 2006
Letters in Applied Microbiology
Volume 44, Issue 2, pages 218–223, February 2007
How to Cite
Jensen, R.L., Pedersen, K.S., Loeschcke, V., Ingmer, H. and Leisner, J.J. (2007), Limitations in the use of Drosophila melanogaster as a model host for gram-positive bacterial infection. Letters in Applied Microbiology, 44: 218–223. doi: 10.1111/j.1472-765X.2006.02040.x
- Issue published online: 29 SEP 2006
- Article first published online: 29 SEP 2006
- 2006/0460: received 4 April 2006, revised 23 August 2006 and accepted 24 August 2006
- model host organism;
- opportunistic infection;
Aims: To examine sensitivities of various Drosophila melanogaster strains towards human pathogenic and nonpathogenic gram-positive bacteria.
Methods and Results: The D. melanogaster Oregon R strain was infected by injecting the thorax with a needle containing Escherichia coli (negative control), Listeria monocytogenes, Staphylococcus aureus (both food-borne pathogens), Listeria innocua, Bacillus subtilis, Carnobacterium maltaromaticum, Lactobacillus plantarum or Pediococcus acidilactici (all nonpathogenic bacteria). Listeria monocytogenes and S. aureus killed the host rapidly compared with the negative control. Infection with L. innocua, B. subtilis or C. maltaromaticum also resulted in a high fly mortality, whereas Lact. plantarum and P. acidilactici resulted in a slightly increased mortality. Four additional D. melanogaster lines, three of which had been selected for heat, cold and desiccation resistance respectively, were subjected to infection by L. monocytogenes, S. aureus and E. coli. Mortality rates were comparable with that of the Oregon R strain.
Conclusions: Use of the injection method shows the limitation of D. melanogaster as a model host for gram-positive bacteria as opportunistic infection by nonpathogenic gram-positive bacteria results in partial or high mortality. In addition, lines of fruit flies resistant to various stress exposures did not show an increased resistance to infection by gram-positive pathogens under the conditions tested.
Significance and Impact of the Study: This study demonstrates the inadequacy of D. melanogaster infected by the injection method in order to distinguish between virulent and nonvirulent gram-positive bacteria.