Comparative Chloroplast Genome Analysis of Single-Cell C4 Bienertia Sinuspersici with Other Amaranthaceae Genomes

Bienertia sinuspersici is a single-cell C4 (SCC4) plant species whose photosynthetic mechanisms occur in two cytoplasmic compartments containing central and peripheral chloroplasts. The efficiency of the C4 photosynthetic pathway to suppress photorespiration and enhance carbon gain has led to a growing interest in its research. A comparative analysis of B. sinuspersici chloroplast genome with other genomes of Amaranthaceae was conducted. Results from a 70% cut off sequence identity showed that B. sinuspersici is closely related to Beta vulgaris with slight variations in the arrangement of few genes such ycf1 and ycf15; and, the absence of psbB in Beta vulgaris. B. sinuspersici has the largest 153, 472 bp while Spinacea oleracea has the largest protein-coding sequence 6,754 bp larger than B. sinuspersici. The GC contents of each of the species ranges from 36.3 to 36.9% with B. sinuspersici having the same GC percentage as Haloxylon persicum and H. ammodendron (36.6%). The IR size also varies yet in all six species, the Ira/LSC border is generally located upstream of the trnH-GUG gene. A total of 107 tandem repeats were found in each of the species, most of which are situated in the intergenic space. These results provide basic information that may be valuable for future related studies