Complete Mitochondrial Genomic Characteristics and Phylogenetic Analysis of the Medicinal Plant Peperomia leptostachya

<b>Background</b>: <i>Peperomia leptostachya</i> is a herbaceous plant with significant medicinal value. To elucidate its mitochondrial genomic characteristics, this study conducted a systematic analysis. <b>Methods</b>: The mitochondrial genome of <i>P. leptostachya</i> was assembled, annotated, and subjected to comparative analysis. <b>Results</b>: (1) The genome exhibits significant structural peculiarities, presenting as an atypical circular structure accompanied by an independent minicircle, forming a multi-branched reticulate configuration spanning a total length of 981,249 bp. Within the mitochondrial genome of <i>P. leptostachya</i>, a total of 52 genes have been identified, including 35 PCGs, 14 tRNAs and 3 rRNAs. (2) A phylogenetic tree was built for 22 species based on the DNA sequences. <i>P. leptostachya</i> belongs to the family Piperaceae within the order Piperales and is closely related to <i>Piper nigrum</i>. (3) Homologous colinear blocks were detected between <i>P. leptostachya</i> and its close relatives, though these blocks exhibited short lengths. Additionally, blank regions were identified that showed no homology with other species. Mitochondrial genomes of <i>P. leptostachya</i> and two close relatives had inconsistent collinear block arrangements. The mitochondrial genome of <i>P. leptostachya</i> had undergone genomic rearrangement relative to closely related species. <b>Conclusions</b>: This study lays the foundation for research into the genetic characteristics and biological traits of <i>P. leptostachya</i>.