ss&rd_004

Following the extraction of total RNA from bacterial cultures at an OD600 of 0.4–0.6 using Trizol, we purified 20 micrograms (ug) RNA with a concentration of 200 nanograms per microliter (ng/μl), using 0.8 volume of SPRIselect Beads (Beckman Coulter, IN, USA) to remove small RNA fragments (size select). Subsequently, ribosomal RNA in size selected RNA was depleted with RiboMinus™ Transcriptome Isolation Kit, bacteria (Invitrogen). The amount of size selected RNA for ribosome-depleted was 15 ug per reaction. Poly(A) tailing was conducted to the ribosome-depleted RNA using E. coli Poly(A) Polymerase (New England Biolabs, MA, USA). The native RNA of preparation was completed.