Assembly and Characterization of the Complete Mitochondrial Genome of Flemingia philippinensis Merr. et Rolfe

Flemingia philippinensis Merr. et Rolfe (F. philippinensis) is a Chinese herbal medicine rich in polyphenols, especially isoflavone derivatives. It exhibits potent anti-inflammatory properties and is widely used in the treatment of various diseases. In this study, we aim to sequence, assemble, and analyze the mitogenome of F. philippinensis in detail to understand the genetic structure of their organelles and their gene expression. The results showed that the mitogenome of F. philippinensis possesses a circular architecture with a total length of 427,353 bp and a GC content of 44.90%. Annotation results revealed 33 unique protein-coding genes (PCGs), 16 transfer RNA (tRNA), and 3 ribosomal RNA (rRNA) genes in the mitogenome. Furthermore, comparative analysis of mitogenome andchloroplast gemone (cpgemone) sequences identified six mitochondrial plastid sequences (MTPTs), including one partial PCG and five complete tRNA genes. Subsequent collinearity analysis indicated that numerous homologous collinear blocks were detected between F. philippinensis and its closely related species, and have undergone a large number of genomic rearrangements in the F. philippinensis mitogenome. Finally, RNA editing analysis identified 498 C -to- U editing sites, notably enriched in nad4 (44 sites) and ccmB (33 sites). Codon usage bias analysis indicated that leucine (Leu 10.66%) and serine (Ser 9.19%) were the most frequently used amino acids. This study lays a theoretical foundation for further elucidating the structural characteristics and understanding the evolution, classification, and identification of F. philippinensis.