Complete chloroplast
genome assembly of Alternanthera denticulata R.Br. 1810 (Amaranthaceae): insight
to potential marker and phylogenetic analysis
Krishnamoorthy Devanathan, Nithaniyal Stalin, Govindan Ganesan and Balaji Raju
Res. J. Biotech.; Vol. 20(12); 17-22;
doi: https://doi.org/10.25303/2012rjbt017022; (2025)
Abstract
Alternanthera denticulata R.Br. is a unique traditional medicinal plant from Amaranthaceae
requiring potential genetic exploration. This study aimed to assemble the complete
chloroplast (cp) genome of A. denticulata and compare it with the existing published
cp genome of the congenerics A. philoxeroides and A. sessilis. The assembled cp
genome, with a size of 151,978 bp, exhibits a typical quadripartite structure. The
large single-copy (LSC) region spans 84,529 bp and the small single-copy (SSC) region
spans 17,281 bp, together comprising of 67% of the genome. The pair of inverted
repeats (IRA and IRB) is each 25,084 bp, covering the remaining 33% of the genome.
A total of 129 valuable genes were identified, including 88 protein-coding genes,
33 tRNA genes and 8 rRNA genes.
Phylogenetic analysis using complete cp genomes from 11 species in the Amaranthaceae
indicated that A. denticulata, A sessilis and A. philoxeroides form a monophyletic
clade. Notably, the ycf1 gene in the LSC region was more divergent in A. denticulata,
A. sessilis and A. philoxeroides. Given the low levels of taxonomic expertise and
clarity in species delineation within the Alternanthera genus, the genetic dataset
generated from this study provides nucleotide insights for identifying new DNA barcode
marker for herbal drug authentication of Alternanthera. The DNA barcode based identification
enhances the discriminatory power of species identification within the congeners
beyond morphological methods and thus will be useful in the wide aspects of plants
breeding, authentication of functional foods and evolutionary studies.
