Differential expression of E.coli mar/rob/soxS triple mutant and wild type in a mouse model of pyelonephritis

Mutation of marA, rob, and soxS causes a clinical strain of E.coli to be attenuated at d3 post-infection in a mouse model of pyelonephritis, here we extract RNA at d2 post infection to analyze transcriptional differences between the two strains. In order to purify enough bacterial RNA to perform microarray, we chose a time point (day 2 post-infection) just before the triple mutant begins to decrease in bacterial load. Mouse kidneys were extracted, homogonized, and samples were pooled in RNALater (Ambion) before extraction and analysis of the transcriptomes