library_construction_protocol: Genomic DNA was isolated from bacteria using a standard protocol (cell lysis, protein precipitation and DNA purification by isopropanol precipitation) Purified genomic DNA was sheared into 200-500 bp fragments and libraries were constructed for Illumina sequencing by PCR amplification using a universal P5-ME primer annealing to the transposon and a specific index primer annealing to adaptor-ligated sheared DNA fragments.