The mitogenomes characterization of two Peltigera species (Peltigera elisabethae and Peltigera polydactylon) and comparative mitogenomic analyses of six Peltigera

In the present study, the mitochondrial genomes of Peltigera elisabethae and P. polydactylon were sequenced and assembled. The two mitogenomes were composed of circular DNA molecules, with sizes of 64,034 bp and 59,208 bp, respectively. Comparative analysis showed that the genome size, GC content, GC skew, and AT skew varied between the two mitochondrial genomes. In codon analysis, phenylalanine (Phe), isoleucine (Ile), and leucine (Leu) were most frequently used in six Peltigera genomes. Evolutionary analysis showed that all 14 protein-coding genes (PCGs) were subject to purifying selection in the six Peltigera species. Regarding gene rearrangement, the PCGs of Peltigera had the same gene sequence and gene content, and a few intron sequences and spacer sequences were rearranged in Peltigera. In the phylogenetic analysis, we used Bayesian and ML methods to construct a phylogenetic tree. Two phylogenetic trees with consistent topology with high support indicate that mitochondrial genes were reliable molecular markers for analyzing the phylogenetic relationships. The present study enriches the mitochondrial genome data of Peltigera and promotes further understanding of the genetics and evolution of the Peltigera genus.