Structure and Phylogeny of Chloroplast and Mitochondrial Genomes of a Chlorophycean Algae (Scenedesmaceae, Sphaeropleales).

is a green alga of commercial interest in sewage purification. Clarification of its organelle genomes is helpful for genetic manipulation, taxonomic revisions and evolutionary research. Here, de novo sequencing was used to determine chloroplast genome and mitochondrial genome of strain F34. The chloroplast genome was composed of a large single-copy (LSC) region of 99,156 bp, a small single-copy (SSC) region of 70,665 bp, and a pair of inverted repeats (IRs) with a length of 13,494 bp each separated by LSC and SSC. The chloroplast genome contained 69 protein-coding genes, 25 transfer-RNA (tRNA) genes, 3 ribosomal RNA (rRNA) genes. The mitochondrial genome was 32,195 bp in length and consisted of 46 unique genes, including 16 protein-coding genes, 27 tRNA genes and 3 rRNA genes. The predominant mutations in organelle genomes were T/A to G/C transitions. Phylogenic analysis indicated was a sister species to and sp. within the genus. In analysis with CGView Comparison Tool, organelle genomes displayed the highest sequence similarity with that of . These findings advanced research on the taxonomy and phylogeny of Chlorophyceae algae and particularly revealed the role of in microalgae evolution.