Project description:To explore the role of Brucella BI-1 in Brucella suis S2, we constructed the Brucella BI-1 deletion mutant strain and its complementary strain. We then determined the effect of Brucella BI-1 deletion on the physiological characteristics of Brucella suis S2 and revealed them via integrated transcriptomic and proteomic analyses. Brucella BI-1 deletion altered the membrane properties of Brucella suis S2 and decreased its resistance to acidic pH, H2O2, polymyxin B, and lincomycin. Additionally, deleting Brucella BI-1 led to defective growth, cell division, and viability in Brucella suis S2. In conclusion, our results revealed that Brucella BI-1 is a bacterial cytoprotective protein involved in membrane homeostasis, cell division, and stress resistance in Brucella suis S2.
Project description:In order to uncover transcriptional changes occurring in Brucella- infected mouse brains that might lead to neurologic complications, we infected susceptible mice intranasally with Brucella and harvested their brains.
Project description:Brucella spp. is an intracellular pathogen in vivo. The intracellular B. melitensis transcriptome was determined by initially enriched and then amplified B. melitensis RNA from total RNA of B. melitensis-infected HeLa cells. Analysis of microarray results identified 161 and 115 genes differentially expressed at 4 and 12 h p.i., respectively. Most of the genes (78%) differentially expressed were down-regulated at the earliest time point, but up-regulated (75%) at 12 h p.i. The analysis of the results indicates that Brucella undergo an adaptation period during the first 4 h p.i. that is overcome by 12 h p.i., permitting Brucella to replicate intracellularly. Specific genes and biological processes identified in this study will further help elucidate how Brucella act during the early infectious process to their eventual benefit and to the detriment of the naïve host. Keywords: Time course study of intracellular B. melitensis gene expression
