library_construction_protocol: Cells from samples were immediately collected by centrifuging and rapidly frozen with liquid nitrogen. Total RNA was extracted using the E.Z.N.A.TM Bacterial RNA Kit (Omega, USA). Genomic DNA was removed with RNase-free DNase I (TaKaRa, Japan). Purified RNA was quantified by Nanodrop 2000. RNA quality was detected by agarose gel electrophoresis and an Agilent 2100 Bioanalyzer system (Agilent Technologies, USA). Paired-end RNA-Seq sequencing libraries were constructed by TruSeqTM RNA sample preparation Kit (Illumina, USA)