Caburatan L , Park J *
Chloroplasts are semi-autonomous organelles needful for the food manufacturing system of plants. Chloroplast genomes are widely studied nowadays for comparative analysis which may help elucidate the differences between species of the same plant family. Suaeda aralocaspica is a single-cell C4 plant species belonging to the family Amaranthaceae under subfamily Suaedoideae. However, not all plant species under Suaedoideae utilize C4 photosynthesis as most of its plant species utilize C3 photosynthesis. This study therefore aims to evaluate the chloroplast genome of S. aralocaspica and conduct a comparative analysis with four other Amaranthaceae species. Chloroplast genome of S. aralocaspica was obtained by chloroplast isolation and DNA sequencing as well as by genome assembly and annotation. Genome comparison was conducted by sequence analysis of genes as well as the determination of tandem repeats. S. aralocaspica is 151,225 bp length with a coding size of 77,517 bp. It has a total of 140 genes, 86 of which are protein-coding. There are 20 duplicated genes in both IRa and IRb and there are 16 intron-containing genes. Results from 70% cut off sequence identity showed that S. aralocaspica varied with other species more apparently in the arrangement of few genes such as matK, atpF, rpoC2, rpoC1, ycf6, psbM, clpP, petB, rpl16, ndhA, and ycf1. A total of 66 tandem repeats were found in all of the studied species, most of which is situated in the intergenic space. Comparative chloroplast genome analysis showed that S. aralocaspica is much closer to Suaeda glauca and a little in variance with Suaeda acuminata and the outgroup, Salsola tragus.