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Sergey Vladimirovich Tarlachkov
Irina Pavlovna Starodumova


Summary: The TaxonDC program (Taxon Distance Calculator) performs pairwise sequence alignment followed by determining the similarity value between two or more sequences of interest. Unlike widely used programs, TaxonDC makes only pairwise alignment of input sequences that allows avoiding different similarity values depending on the sequences included in the analysis. The similarity values calculated with TaxonDC are the same compared to those calculated using popular identification oriented web-based tool EzBioCloud that makes calculated values comparable with previous ones. In addition, to help prevent discrepancy among different researchers, the problem concerning the influence of the order of entered sequences on similarity values is specially considered. To our knowledge, TaxonDC is the only software which includes these capabilities in combination, simplifies and widens calculation of similarity values in systematics of prokaryotes and eukaryotes. The program has easy-to-use interface and can be run on Windows and Linux.

Availability and Implementation: The program is available free of charge at

Supplementary information: Supplementary data are available at Journal of Bioinformatics and Genomics online.

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How to Cite
TARLACHKOV, Sergey Vladimirovich; STARODUMOVA, Irina Pavlovna. TAXONDC: CALCULATING THE SIMILARITY VALUE OF THE 16S RRNA GENE SEQUENCES OF PROKARYOTES OR ITS REGIONS OF FUNGI. Journal of Bioinformatics and Genomics, [S.l.], n. 3 (5), oct. 2017. ISSN 2530-1381. Available at: <>. Date accessed: 13 dec. 2017. doi:
Sequence analysis
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