Gene expression profiles of wild-type Yersinia pestis CO92 and its Braun lipoprotein mutant at flea and human temp

ABSTRACT: Braun/murein lipoprotein (Lpp) is one of the major outer membrane components of gram-negative bacteria belonging to the enterobacteriaceae family that that is involved in inflammatory responses and septic shock. We previously characterized a delta-lpp isogenic mutant of Yersinia pestis CO92 and found that this mutant was defective in surviving in macrophages and was attenuated in a mouse inhalation model of plague when compared to the highly virulent wild-type (WT) bacterium. To better understand how deletion of the lpp gene might affect Yersinia virulence, we performed global transcriptional profiling of the genes in the WT Y. pestis CO92 and its delta-lpp mutant by using microarrays. The organisms were cultured at both 26 and 37 degrees Celsius to simulate the flea vector and mammalian host environments, respectively. Our data revealed vastly different effects of lpp mutation on the transcriptomes of Y. pestis grown at 37 versus 26°C. While the absence of Lpp resulted mainly in the down-regulation of metabolic genes at 26°C, the Y. pestis CO92 lpp mutant cultured at 37°C exhibited profound alterations in stress response and virulence genes, compared to the WT bacterium. We further investigated one of the stress-related genes (htrA) down-regulated in the lpp mutant relative to WT Y. pestis, as HtrA was previously shown to be important for intracellular survival of Y. enterocolitica in macrophages. Indeed, complementation of the delta-lpp mutant with the htrA gene in trans restored intracellular survival of the Y. pestis lpp mutant. Our results support a role for Lpp in Y. pestis CO92 adapatation to the host environment, possibly via transcriptional activation of htrA.

ORGANISM(S): Yersinia pestis Yersinia pestis CO92

PROVIDER: GSE19840 | GEO | 2010/06/04

SECONDARY ACCESSION(S): PRJNA122061

REPOSITORIES: GEO