SRA

Purpose: To determine how divergent strains of C. difficile respond to environmental changes, the transcriptomes of two historic and two recently isolated hypervirulent strains were analyzed following nutrient shift and osmotic shock. Methods: Following nutrient shift and osmotic shock, mRNA profile were determined using sequing of transcriptome in biological duplicates, using Illumina Hi-seq 2000. Results: After applying the quality control steps, for each sample, sequence reads were 90 nucleotides in length and the total number of reads per sample was ~ 26.6 million on average. Expression of more than 90% CDS was detected under the three experimental conditions combined. About 20% of these genes were indentified to be differentially expressed at 1.5 fold or more. Conclusions: Our results reveal that although C. difficile strains contain a large number of shared and strain specific genes, the majority of the differentially expressed genes were core genes. We also detected a number of transcriptionally active regions that were not part of the primary genome annotation. Some of these are likely to be small regulatory RNAs. Overall design: Differential stress transcriptomes of two historic (strain 630 and 196) and two recently emerged hypervirulent strains (stain R20291 and 32g58) of C. difficile was determined by deep sequencing, in duplicate, using Illumina Hi-Seq 2000.