Induction of dnaK through its native heat shock promoter is necessary for intramacrophagic replication of Brucella suis.
The heat shock protein DnaK is essential for intramacrophagic replication of Brucella suis. The replacement of the stress-inducible, native dnaK promoter of B. suis by the promoter of the constitutively expressed bla gene resulted in temperature-independent synthesis of DnaK. In contrast to a dnaK null mutant, this strain grew at 37 degrees C, with a thermal cutoff at 39 degrees C. However, the constitutive dnaK mutant, which showed high sensitivity to H(2)O(2)-mediated stress, failed to multiply in murine macrophage-like cells and was rapidly eliminated in a mouse model of infection, adding strong arguments to our hypothesis that stress-mediated and heat shock promoter-dependent induction of dnaK is a crucial event in the intracellular replication of B. suis.
Köhler
Stephan
S
Institut National de la Santé et de la Recherche Médicale U-431, Université Montpellier II, F-34095 Montpellier, France. kohler@crit.univ-montp2.fr
Ekaza
Euloge
E
Paquet
Jean-Yves
JY
Walravens
Karl
K
Teyssier
Jacques
J
Godfroid
Jacques
J
Liautard
Jean-Pierre
JP
D000818:Animals; D002002:Brucella / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D002006:Brucellosis; D004338:Drug Combinations; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D018869:Heat-Shock Response / Q000235:genetics*; D008264:Macrophages / Q000382:microbiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009154:Mutation; D009821:Oils; D018384:Oxidative Stress; D010636:Phenols; D011401:Promoter Regions, Genetic; D013154:Spleen / Q000382:microbiology
D004338:Drug Combinations; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D009821:Oils; C027222:P & S Liquid; D010636:Phenols; C063842:dnaK protein, E coli