Fig. 1

The pipeline of Fosmid-size long paired-end library construction. The red area represents the vector, the blue area represents the large inserted genomic fragment, and the yellow area represents the Ampicillin resistance gene tag. The Fosmid clones were pooled together, and DNA was extracted for paired-end library construction. Pooled Fosmid plasmid DNA was sheared into ~ 15 kb fragments by g-TUBE (Covaris). It generated insert only, vector with single-ends and vector with paired-ends. Then, these DNA fragments were end repaired and gel purified for ligation with the Ampicillin resistance gene tag. Although all fragments could be ligated to the Ampicillin resistance gene tag, only those containing the chloramphenicol resistant gene and oriV ligated to an Amp tag were screened out with double resistance to chloramphenicol and ampicillin after transformation. Finally, the vector was removed by I-SceI and the paired-end fragments with the Amp tag were sequenced on PacBio