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

Background: Peperomia leptostachya is a herbaceous plant with significant medicinal value. To elucidate its mitochondrial genomic characteristics, this study conducted a systematic analysis. Methods: The mitochondrial genome of P. leptostachya was assembled, annotated, and subjected to comparative analysis. Results: (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 P. leptostachya, 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. P. leptostachya belongs to the family Piperaceae within the order Piperales and is closely related to Piper nigrum. (3) Homologous colinear blocks were detected between P. leptostachya 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 P. leptostachya and two close relatives had inconsistent collinear block arrangements. The mitochondrial genome of P. leptostachya had undergone genomic rearrangement relative to closely related species. Conclusions: This study lays the foundation for research into the genetic characteristics and biological traits of P. leptostachya.