[
International Worm Meeting,
2003]
The free-living nematode Caenorhabditis elegans has been used to model bacterial pathogenesis in several studies [1]. One weakness of the model is that C. elegans has only been cultured up to a temperature of 25 degrees C [2]. Many bacterial pathogens use environmental stimuli to regulate expression of virulence determinates. One such stimulus is temperature. Bacterial pathogens from the genus Yersinia induce transcription of many of their virulence determinates in response to a temperature of 37 degrees C [3]. We have screened four free-living, bactovorus nematode species for temperature tolerance. The gonochoristic nematode, Panagrellus redivivus strain MT8872 had a high thermotolerance. The gender of P. redivivus was not found to effect the rate of killing or thermotolerance. Temperature had a negative effect on P. redivivus lifespan when fed the non-pathogen Escherichia coli and to a lesser extent when fed the pathogen Pseudomonas aeruginosa. In addition, no strains of Yersinia pseudotuberculosis were shown to be pathogenic to P. redivivus , either at 25 degrees C or at 37 degrees C. 1.Ewbank J, Tackling both sides of the host-pathogen equation with Caenorhabditis elegans. Microbes and Infection, 2002. 4: p. 247-256. 2.Klass MR, Aging in the nematode Caenorhabditis elegans: major biological and environmental factors influencing life span. Mechanisms of Ageing and Development, 1977. 6: p. 413-429. 3.Konkel ME and Tilly K, Temperature-regulated expression of bacterial virulence genes. Microbes and Infection, 2000. 2: p. 157-166. Crown Copyright copyright Dstl 2003