In the three animal models described P. morganii strains behaved similarly to E. coli strains studied previously. A marked difference could be observed between the virulence of wild-type haemolytic and nonhaemolytic strains. The rapid appearance of fatal haemorrhagic lung oedema in the lung toxicity assay and the very short survival time in mice infected intraperitoneally with Hly+ strains suggest that a toxic effect may be mainly responsible for the enhanced virulence of alpha-haemolysin-producing strains. The parallel loss of alpha-haemolytic capacity and enhanced virulence in actinomycin-D-treated derivatives also supports this idea.
ASJC Scopus subject areas
- Molecular Biology