Taxonomic classification of 2616 strains belonging to the Bacillus subtilis group

PETITTI, T.; TORRES MANNO, M.; DAURELIO, L.D.; ESPARIZ, M.

Workshop; 18th Student Council Symposium; 2022

International Society for Computational Biology

BackgroundThe genus Bacillus is formed by multiple groups, among them, the Bacillus subtilis group stands out. The Bacillus subtilis group is usually classified in 5 groups or clades, Subtilis clade, Amyloliquefaciens clade, Gobiensis clade, Pumilus clade, and Licheniformis clade. Nevertheless, due to the high diversity of the group, the taxonomic classification is challenging, having reported multiple cases of incorrect classifications or incoherences between taxonomic classification and genomic or phenotypic characteristics. However, the proper assignment is critical since these assignments are used to estimate the performance and safety of bacteria, which has an impact on their use in industry and agriculture.FindingsWe downloaded from GenBank, 2400 sequences belonging to the five clades, and 225 genomes provided by a collaborator. These genomes were quality filtered, eliminating 133 sequences.The species-level taxonomic identity of the 2492 remaining strains was validated or reassigned using Average Nucleotide Identity (ANI) and multi-locus sequence analysis (MLSA). Thus, 29.5% of the sequences were reassigned. In turn, 148 strains were classified as new genomospecies, named genomospecies 1 to 12.ConclusionsFrom the results obtained, it is possible to see the need to find new and better techniques that allow classifying species with greater precision. Due to this we are developing a bioinformatic tool using AI, which allows using validated genetic markers to have a precision similar to that obtained through these manual analyses and greater than that obtained through markers such as 16S. Therefore, this tool would allow mass assignments in metagenomic analysis, as well as assignments of new isolates of the group, with good precision and faster than actual methods.