Development of a competitive index assay to evaluate the virulence of Listeria monocytogenes actA mutants during primary and secondary infection of mice.
We developed a competitive index assay for murine listeriosis that tests the virulence of Listeria monocytogenes strains in different organs and at various times postinoculation. Studies presented here demonstrate the reproducibility of this assay during primary and secondary infection of inbred and outbred mice. We verified the validity of this assay by performing competitive index analysis of a well-characterized strain of L. monocytogenes lacking the actA gene. In addition, we found that while L. monocytogenes strains unable to recruit vasodilator-stimulated phosphoprotein (VASP) to their surface exhibit a 10-fold virulence attenuation in the livers of naive animals, they display a 50-fold survival defect in the liver during secondary listeriosis.
Auerbuch
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Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA.
Lenz
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LL
Portnoy
D A
DA
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D005260:Female; D008089:Listeria monocytogenes / Q000235:genetics / Q000472:pathogenicity*; D008088:Listeriosis / Q000276:immunology / Q000382:microbiology*; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins; D009154:Mutation; D010750:Phosphoproteins / Q000378:metabolism; D015203:Reproducibility of Results; D014774:Virulence; D000098662:Vasodilator-Stimulated Phosphoprotein
D001426:Bacterial Proteins; D015815:Cell Adhesion Molecules; D008565:Membrane Proteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; D000098662:Vasodilator-Stimulated Phosphoprotein; C072980:actA protein, Listeria monocytogenes