Categories of sequencing reads inferred from the PacBio NGS sequencing.

(A) Categories of sequencing reads deriving from the gapC amplicon, (B) i6-tubA amplicon and (C) i5-tubA amplicon, respectively. Number and percentage of particular types of reads are given. The distribution of introns in all groups of reads is depicted. Lines represent the exons while circles represent the introns: black circles: conventional introns; white: nonconventional ones (not to scale). Introns are labelled i1 –i6. In addition, introns that exhibit intermediate features are marked with an asterisk. Double asterisk indicates the introns to which the reverse primer was targeted, thus not considered in the analysis of amplicons (introns to which primers annealed were inevitably present in the amplification products).