Transcriptomic study of single mutant hns and hns2 from enteroaggregative E. coli 042 by RNA-seq

Bacterial genomes encode in many instances more than one copy of genes coding for global modulators. The enteroaggregative E. coli strain 042 encodes, in addition to the hns and stpA genes, an additional hns-like gene, hns2. We have previously determined the patterns of the H-NS2 regulation in cells grown at 37ºC by using RNA-seq (see https://doi.org/10.1128/mSystems.00220-17). In this work, we used RNA-seq to compare the transcriptome of the wt strain and its hns and hns2 derivatives grown at 25ºC in LB medium. E. coli 042 and derivative mutants hns and hns2 mRNA profiles were generated by Illumina RNA-seq. RNA extraction, DNase treatment, evaluation of RNA quality and cDNA libraries for Illumina sequencing were performed by Vertis Biotechnologie AG, Freising-Weihenstephan, Germany. Bacterial cells were grown until O.D.600 of 2,0 in LB medium at 25ºC with 200rpm of agitation. Three replicates were grown from each strain, 1 ml of each replicate was collected and bacterial pellets were maintained at -80ºC. Bacterial pellets were sent to Vertis Biotechnologie AG, Freising-Weihenstephan, Germany in dry ice. E. coli 042 wt was used as genome reference (NC_017626 for the chromosome and NC_017627 for the pAA plasmid) for analysis.