Comparative Analysis of Chloroplast Genome of Desmodium stryacifolium with Closely Related Legume Genome from the Phaseoloid Clade

Desmodium styracifolium is a medicinal plant from the Desmodieae tribe, also known as Grona styracifolia. Its role in the treatment of urolithiasis, urinary infections, and cholelithiasis has previously been widely documented. The complete chloroplast genome sequence of D. Styracifolium is 149,155 bp in length with a GC content of 35.2%. It is composed of a large single copy (LSC) of 82,476 bp and a small single copy (SSC) of 18,439 bp, which are separated by a pair of inverted repeats (IR) of 24,120 bp each and has 128 genes. We performed a comparative analysis of the D. styracifolium cpDNA with the genome of previously investigated members of the Sesamoidea tribe and on the outgroup from its Phaseolinae sister tribe. The size of all seven cpDNAs ranged from 148,814 bp to 151,217 bp in length due to the contraction and expansion of the IR/SC boundaries. The gene orientation of the SSC region in D. styracifolium was inverted in comparison with the other six studied species. Furthermore, the sequence divergence of the IR regions was significantly lower than that of the LSC and the SSC, and five highly divergent regions, trnL-UAA-trnT-UGU, psaJ-ycf4, psbE-petL, rpl36-rps8, and rpl32-trnL-UGA, were identified that could be used as valuable molecular markers in future taxonomic studies and phylogenetic constructions.