In:
Infection and Immunity, American Society for Microbiology, Vol. 83, No. 8 ( 2015-08), p. 3233-3242
Abstract:
Certain intracellular bacteria use the host cell cytosol as the replicative niche. Although it has been hypothesized that the successful exploitation of this compartment requires a unique metabolic adaptation, supportive evidence is lacking. For Francisella tularensis , many genes of the Francisella pathogenicity island (FPI) are essential for intracellular growth, and therefore, FPI mutants are useful tools for understanding the prerequisites of intracytosolic replication. We compared the growth of bacteria taken up by phagocytic or nonphagocytic cells with that of bacteria microinjected directly into the host cytosol, using the live vaccine strain (LVS) of F. tularensis ; five selected FPI mutants thereof, i.e., Δ iglA , Δ iglC ̧ Δ iglG , Δ iglI , and Δ pdpE strains; and Listeria monocytogenes . After uptake in bone marrow-derived macrophages (BMDM), ASC −/− BMDM, MyD88 −/− BMDM, J774 cells, or HeLa cells, LVS, Δ pdpE and Δ iglG mutants, and L. monocytogenes replicated efficiently in all five cell types, whereas the Δ iglA and Δ iglC mutants showed no replication. After microinjection, all 7 strains showed effective replication in J774 macrophages, ASC −/− BMDM, and HeLa cells. In contrast to the rapid replication in other cell types, L. monocytogenes showed no replication in MyD88 −/− BMDM and LVS showed no replication in either BMDM or MyD88 −/− BMDM after microinjection. Our data suggest that the mechanisms of bacterial uptake as well as the permissiveness of the cytosolic compartment per se are important factors for the intracytosolic replication. Notably, none of the investigated FPI proteins was found to be essential for intracytosolic replication after microinjection.
Type of Medium:
Online Resource
ISSN:
0019-9567
,
1098-5522
DOI:
10.1128/IAI.00416-15
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2015
detail.hit.zdb_id:
1483247-1
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