Open AccessRole of Tellurite Resistance Operon in Filamentous Growth of Yersinia pestis in Macrophages
Author(s) -
Duraisamy Ponnusamy,
Kenneth D. Clinkenbeard
Publication year - 2015
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0141984
Subject(s) - yersinia pestis , biology , microbiology and biotechnology , operon , mutant , phenotype , virulence , intracellular parasite , gene , intracellular , genetics
Background Yersinia pestis initiates infection by parasitism of host macrophages. In response to macrophage infections, intracellular Y . pestis can assume a filamentous cellular morphology which may mediate resistance to host cell innate immune responses. We previously observed the expression of Y . pestis tellurite resistance proteins TerD and TerE from the terZABCDE operon during macrophage infections. Others have observed a filamentous response associated with expression of tellurite resistance operon in Escherichia coli exposed to tellurite. Therefore, in this study we examine the potential role of Y . pestis tellurite resistance operon in filamentous cellular morphology during macrophage infections. Principal Findings In vitro treatment of Y . pestis culture with sodium tellurite (Na 2 TeO 3 ) caused the bacterial cells to assume a filamentous phenotype similar to the filamentous phenotype observed during macrophage infections. A deletion mutant for genes terZAB abolished the filamentous morphologic response to tellurite exposure or intracellular parasitism, but without affecting tellurite resistance. However, a terZABCDE deletion mutant abolished both filamentous morphologic response and tellurite resistance. Complementation of the terZABCDE deletion mutant with terCDE , but not terZAB , partially restored tellurite resistance. When the terZABCDE deletion mutant was complemented with terZAB or terCDE , Y . pestis exhibited filamentous morphology during macrophage infections as well as while these complemented genes were being expressed under an in vitro condition. Further in E . coli , expression of Y . pestis terZAB , but not terCDE , conferred a filamentous phenotype. Conclusions These findings support the role of Y . pestis terZAB mediation of the filamentous response phenotype; whereas, terCDE confers tellurite resistance. Although the beneficial role of filamentous morphological responses by Y . pestis during macrophage infections is yet to be fully defined, it may be a bacterial adaptive strategy to macrophage associated stresses.