we used mRNA sequencing to compare whole transcriptomes of colistin-resistant and colistin-susceptible A. baumannii strains, with the aim of identifying genes associated with colistin resistance.
Overnight cultures were inoculated 1:100 in LB broth medium without colistin and grown until mid-log phase (OD600=0.5) at 37°C with shaking (180 rpm). Isolated RNA was sent to Macrogen Inc. (Seoul, Korea) for further procedures. After isolation of RNA, cDNA was synthesized and sequencing libraries were generated in strand-specific manner according to the Illumina standard protocol for high-throughput sequencing. Library sequencing was carried out with the Illumina HiSeq TM 2000 sequencer; the SolexaQA program was used to verify sequence quality.