The first complete chloroplast genome sequence of Pentaphragma spicatum Merr. (Pentaphragmataceae) and phylogenetic analysis

Abstract

Pentaphragma spicatum Merr. is an endemic wild edible plant of China belonging to the Pentaphragmataceae family. It is widely consumed by Shangsi County resident in Guangxi Fangchenggang. Initially, Pentaphragma was classified as a genus within the Campanulaceae family, but, later it was treated as part of the Pentaphragmataceae family. However, the chloroplast genome of Pentaphragmataceae has not yet been reported. In this study, we sequenced the first complete chloroplast (cp) genome of P. spicatum from Guangxi, China. The whole genome was 154,229 bp in length, consisting of a pair of inverted repeats (IR each 25,572 bp), a large single-copy region (LSC 84,884 bp), and a small single-copy region (SSC 18,201 bp). The complete genome contained 129 genes, including 87 protein-coding genes, 34 tRNA, and 8 rRNA genes. The overall GC content of the whole genome was 37.71%. Based on a maximum-likelihood phylogenetic analysis, it has been determined that P. spicatum is not phylogenetically related to Campanulaceae and supports the decision to classify it as a separate family, Pentaphragmataceae. The complete chloroplast genome of P. spicatum will help enhance and integrate the existing genome data of Asterales. This will provide insights into the phylogenetic relationship within Campanulaceae.