RNA-Seq of wild type E. coli MG1655 versus those with a deletion in the hns gene (Histone-like protein H-NS)

The aim of the experiment was to determine differences in RNA levels between wild-type E. coli and E. coli with an hns deletion. We used RNA-seq, but to control for variation in sample preparation and sequencing, we combined each E. coli RNA sample with a "spike-in” Salmonella RNA sample of known concentration. Libraries constructed in duplicate from strains grown with and without Salmonella spike-in to assess absolute genome-wide changes in transcription.This allowed us to normalise RNA levels between samples during data analysis.